<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE article PUBLIC "-//NLM//DTD Journal Publishing DTD v2.3 20070202//EN" "journalpublishing.dtd">
<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" article-type="research-article" dtd-version="2.3" xml:lang="EN">
<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">Front. Psychol.</journal-id>
<journal-title>Frontiers in Psychology</journal-title>
<abbrev-journal-title abbrev-type="pubmed">Front. Psychol.</abbrev-journal-title>
<issn pub-type="epub">1664-1078</issn>
<publisher>
<publisher-name>Frontiers Media S.A.</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.3389/fpsyg.2023.1178560</article-id>
<article-categories>
<subj-group subj-group-type="heading">
<subject>Psychology</subject>
<subj-group>
<subject>Original Research</subject>
</subj-group>
</subj-group>
</article-categories>
<title-group>
<article-title>An international consensus definition for contextual factors: findings from a nominal group technique</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname>Cook</surname>
<given-names>Chad E.</given-names>
</name>
<xref rid="aff1" ref-type="aff"><sup>1</sup></xref>
<xref rid="aff2" ref-type="aff"><sup>2</sup></xref>
<xref rid="aff3" ref-type="aff"><sup>3</sup></xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Bailliard</surname>
<given-names>Antoine</given-names>
</name>
<xref rid="aff1" ref-type="aff"><sup>1</sup></xref>
<xref rid="aff4" ref-type="aff"><sup>4</sup></xref>
<uri xlink:href="https://loop.frontiersin.org/people/1362240/overview"/>
</contrib>
<contrib contrib-type="author" corresp="yes">
<name>
<surname>Bent</surname>
<given-names>Jennifer A.</given-names>
</name>
<xref rid="aff5" ref-type="aff"><sup>5</sup></xref>
<xref rid="c001" ref-type="corresp"><sup>&#x002A;</sup></xref>
<uri xlink:href="https://loop.frontiersin.org/people/2222519/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Bialosky</surname>
<given-names>Joel E.</given-names>
</name>
<xref rid="aff6" ref-type="aff"><sup>6</sup></xref>
<xref rid="aff7" ref-type="aff"><sup>7</sup></xref>
<uri xlink:href="https://loop.frontiersin.org/people/2323384/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Carlino</surname>
<given-names>Elisa</given-names>
</name>
<xref rid="aff8" ref-type="aff"><sup>8</sup></xref>
<uri xlink:href="https://loop.frontiersin.org/people/710720/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Colloca</surname>
<given-names>Luana</given-names>
</name>
<xref rid="aff9" ref-type="aff"><sup>9</sup></xref>
<uri xlink:href="https://loop.frontiersin.org/people/346131/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Esteves</surname>
<given-names>Jorge E.</given-names>
</name>
<xref rid="aff10" ref-type="aff"><sup>10</sup></xref>
<xref rid="aff11" ref-type="aff"><sup>11</sup></xref>
<uri xlink:href="https://loop.frontiersin.org/people/966412/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Newell</surname>
<given-names>Dave</given-names>
</name>
<xref rid="aff12" ref-type="aff"><sup>12</sup></xref>
<uri xlink:href="https://loop.frontiersin.org/people/2341624/bio"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Palese</surname>
<given-names>Alvisa</given-names>
</name>
<xref rid="aff13" ref-type="aff"><sup>13</sup></xref>
<uri xlink:href="https://loop.frontiersin.org/people/1104400/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Reed</surname>
<given-names>William R.</given-names>
</name>
<xref rid="aff14" ref-type="aff"><sup>14</sup></xref>
<uri xlink:href="https://loop.frontiersin.org/people/869537/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Vilardaga</surname>
<given-names>Jennifer Plumb</given-names>
</name>
<xref rid="aff15" ref-type="aff"><sup>15</sup></xref>
<uri xlink:href="https://loop.frontiersin.org/people/384842/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Rossettini</surname>
<given-names>Giacomo</given-names>
</name>
<xref rid="aff16" ref-type="aff"><sup>16</sup></xref>
<uri xlink:href="https://loop.frontiersin.org/people/543891/overview"/>
</contrib>
</contrib-group>
<aff id="aff1"><sup>1</sup><institution>Department of Orthopaedics, Duke University</institution>, <addr-line>Durham, NC</addr-line>, <country>United States</country></aff>
<aff id="aff2"><sup>2</sup><institution>Department of Population Health Sciences, Duke University</institution>, <addr-line>Durham, NC</addr-line>, <country>United States</country></aff>
<aff id="aff3"><sup>3</sup><institution>Duke Clinical Research Institute, Duke University</institution>, <addr-line>Durham, NC</addr-line>, <country>United States</country></aff>
<aff id="aff4"><sup>4</sup><institution>Occupational Therapy Doctorate Division, Duke University</institution>, <addr-line>Durham, NC</addr-line>, <country>United States</country></aff>
<aff id="aff5"><sup>5</sup><institution>Department of Rehabilitation, Duke University Hospital System</institution>, <addr-line>Durham, NC</addr-line>, <country>United States</country></aff>
<aff id="aff6"><sup>6</sup><institution>Department of Physical Therapy, University of Florida</institution>, <addr-line>Gainesville, FL</addr-line>, <country>United States</country></aff>
<aff id="aff7"><sup>7</sup><institution>Brooks-PHHP Research Collaboration</institution>, <addr-line>Gainesville, FL</addr-line>, <country>United States</country></aff>
<aff id="aff8"><sup>8</sup><institution>Department of Neuroscience Rita Levi Montalcini, University of Turin</institution>, <addr-line>Turin</addr-line>, <country>Italy</country></aff>
<aff id="aff9"><sup>9</sup><institution>Departement of Pain and Translational Symptom Science and the Placebo Beyond Opinions Center, University of Maryland School of Nursing</institution>, <addr-line>Baltimore, MD</addr-line>, <country>United States</country></aff>
<aff id="aff10"><sup>10</sup><institution>Clinical-Based Human Research Department, Foundation COME Collaboration</institution>, <addr-line>Pescara</addr-line>, <country>Italy</country></aff>
<aff id="aff11"><sup>11</sup><institution>Malta ICOM Educational</institution>, <addr-line>G&#x017C;ira</addr-line>, <country>Malta</country></aff>
<aff id="aff12"><sup>12</sup><institution>Anglo-European College of Chiropractic University College, Bournemouth</institution>, <country>United Kingdom</country></aff>
<aff id="aff13"><sup>13</sup><institution>Department of Medical Sciences, School of Nursing, University of Udine</institution>, <addr-line>Udine</addr-line>, <country>Italy</country></aff>
<aff id="aff14"><sup>14</sup><institution>Department of Physical Therapy, University of Alabama at Birmingham</institution>, <addr-line>Birmingham, AL</addr-line>, <country>United States</country></aff>
<aff id="aff15"><sup>15</sup><institution>Department of Psychiatry and Behavioral Sciences, Duke University</institution>, <addr-line>Durham, NC</addr-line>, <country>United States</country></aff>
<aff id="aff16"><sup>16</sup><institution>School of Physiotherapy, University of Verona</institution>, <addr-line>Verona</addr-line>, <country>Italy</country></aff>
<author-notes>
<fn id="fn0001" fn-type="edited-by"><p>Edited by: Michael Swain, Macquarie University, Australia</p></fn>
<fn id="fn0002" fn-type="edited-by"><p>Reviewed by: Carlo Ammendolia, University of Toronto, Canada; David McNaughton, Macquarie University, Australia</p></fn>
<corresp id="c001">&#x002A;Correspondence: Jennifer A. Bent, <email>Jennifer.bent@duke.edu</email></corresp>
</author-notes>
<pub-date pub-type="epub">
<day>03</day>
<month>07</month>
<year>2023</year>
</pub-date>
<pub-date pub-type="collection">
<year>2023</year>
</pub-date>
<volume>14</volume>
<elocation-id>1178560</elocation-id>
<history>
<date date-type="received">
<day>06</day>
<month>03</month>
<year>2023</year>
</date>
<date date-type="accepted">
<day>07</day>
<month>06</month>
<year>2023</year>
</date>
</history>
<permissions>
<copyright-statement>Copyright &#x00A9; 2023 Cook, Bailliard, Bent, Bialosky, Carlino, Colloca, Esteves, Newell, Palese, Reed, Vilardaga and Rossettini.</copyright-statement>
<copyright-year>2023</copyright-year>
<copyright-holder>Cook, Bailliard, Bent, Bialosky, Carlino, Colloca, Esteves, Newell, Palese, Reed, Vilardaga and Rossettini</copyright-holder>
<license xlink:href="http://creativecommons.org/licenses/by/4.0/">
<p>This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.</p>
</license>
</permissions>
<abstract>
<sec>
<title>Objective</title>
<p>Emerging literature suggests contextual factors are important components of therapeutic encounters and may substantially influence clinical outcomes of a treatment intervention. At present, a single consensus definition of contextual factors, which is universal across all health-related conditions is lacking. The objective of this study was to create a consensus definition of contextual factors to better refine this concept for clinicians and researchers.</p>
</sec>
<sec>
<title>Design</title>
<p>The study used a multi-stage virtual Nominal Group Technique (vNGT) to create and rank contextual factor definitions. Nominal group techniques are a form of consensus-based research, and are beneficial for identifying problems, exploring solutions and establishing priorities.</p>
</sec>
<sec>
<title>Setting</title>
<p>International.</p>
</sec>
<sec>
<title>Main outcome measures</title>
<p>The initial stages of the vNGT resulted in the creation of 14 independent contextual factor definitions. After a prolonged discussion period, the initial definitions were heavily modified, and 12 final definitions were rank ordered by the vNGT participants from first to last.</p>
</sec>
<sec>
<title>Participants</title>
<p>The 10 international vNGT participants had a variety of clinical backgrounds and research specializations and were all specialists in contextual factors research.</p>
</sec>
<sec>
<title>Results</title>
<p>A sixth round was used to identify a final consensus, which reflected the complexity of contextual factors and included three primary domains: (1) an overall definition; (2) qualifiers that serve as examples of the key areas of the definition; and (3) how contextual factors may influence clinical outcomes.</p>
</sec>
<sec>
<title>Conclusion</title>
<p>Our consensus definition of contextual factors seeks to improve the understanding and communication between clinicians and researchers. These are especially important in recognizing their potential role in moderating and/or mediating clinical outcomes.</p>
</sec>
</abstract>
<kwd-group>
<kwd>placebo</kwd>
<kwd>contextual factors</kwd>
<kwd>clinical outcomes</kwd>
<kwd>nominal group technique</kwd>
<kwd>consensus research</kwd>
</kwd-group>
<counts>
<fig-count count="1"/>
<table-count count="4"/>
<equation-count count="0"/>
<ref-count count="35"/>
<page-count count="10"/>
<word-count count="7744"/>
</counts>
<custom-meta-wrap>
<custom-meta>
<meta-name>section-at-acceptance</meta-name>
<meta-value>Psychology for Clinical Settings</meta-value>
</custom-meta>
</custom-meta-wrap>
</article-meta>
</front>
<body>
<sec id="sec1" sec-type="intro">
<title>Introduction</title>
<p>Tools such as patient reported outcome measures (PROMs), physical performance measures, and patient experience measures, are used to measure a patient&#x2019;s health outcomes (<xref ref-type="bibr" rid="ref11">Herbert et al., 2005</xref>), and are influenced by a number of internal (within the person) and external (outside the person) factors. These factors may include comorbidities (<xref ref-type="bibr" rid="ref33">Tousignant-Laflamme et al., 2017</xref>), cognition and mood (<xref ref-type="bibr" rid="ref33">Tousignant-Laflamme et al., 2017</xref>), socioeconomic and social status (<xref ref-type="bibr" rid="ref4">Rethorn et al., 2022</xref>; <xref ref-type="bibr" rid="ref29">Sharpe et al., 2023</xref>), and care timing and provider specialization (<xref ref-type="bibr" rid="ref24">Ojha et al., 2016</xref>; <xref ref-type="bibr" rid="ref12">Hudon et al., 2019</xref>; <xref ref-type="bibr" rid="ref15">Lentz et al., 2020</xref>). Targeted treatment/interventions may also influence outcomes but are commonly moderated and/or mediated by factors such as expectations (<xref ref-type="bibr" rid="ref1">Bishop et al., 2013</xref>; <xref ref-type="bibr" rid="ref7">Eklund et al., 2019</xref>), aspects of the patient-clinician relationship (<xref ref-type="bibr" rid="ref14">Kelley et al., 2014</xref>), legal status (<xref ref-type="bibr" rid="ref26">Rodeghero et al., 2015</xref>), workers compensation (<xref ref-type="bibr" rid="ref26">Rodeghero et al., 2015</xref>), social risk variables (<xref ref-type="bibr" rid="ref4">Rethorn et al., 2022</xref>; <xref ref-type="bibr" rid="ref29">Sharpe et al., 2023</xref>), common factors such as engagement and/or interaction skills (<xref ref-type="bibr" rid="ref21">Miciak et al., 2012</xref>), and natural history (<xref ref-type="bibr" rid="ref6">Centers of Disease Control and Prevention, 2012</xref>). These factors influence disparate individuals differently; consequently, understanding the role that interventions contribute toward patient outcomes becomes challenging.</p>
<p>The ecological landscape in which the clinical encounter occurs, which is sometimes referred to as therapeutic context, consists of a range of factors increasingly referred to as contextual factors (<xref ref-type="bibr" rid="ref18">McLaren and Hawe, 2005</xref>). Although increasingly well studied, contextual factors/effects are defined differently across a majority of studies (<xref ref-type="bibr" rid="ref13">Kaplan et al., 2010</xref>; <xref ref-type="bibr" rid="ref14">Kelley et al., 2014</xref>; <xref ref-type="bibr" rid="ref32">Testa and Rossettini, 2016</xref>; <xref ref-type="bibr" rid="ref23">Nielsen et al., 2019</xref>, <xref ref-type="bibr" rid="ref22">2021</xref>; <xref ref-type="bibr" rid="ref27">Rollet et al., 2021</xref>; <xref ref-type="bibr" rid="ref28">Sevilla Guerra et al., 2022</xref>; <xref ref-type="bibr" rid="ref30">Sherriff et al., 2022</xref>). Definitions have included sociodemographic variables (<xref ref-type="bibr" rid="ref23">Nielsen et al., 2019</xref>), person-related factors (race, age, patient beliefs and characteristics) (<xref ref-type="bibr" rid="ref23">Nielsen et al., 2019</xref>), and physical and social environments (<xref ref-type="bibr" rid="ref28">Sevilla Guerra et al., 2022</xref>). At a micro-level, contextual factors have been defined by seemingly disparate terms such as therapeutic alliance (<xref ref-type="bibr" rid="ref14">Kelley et al., 2014</xref>), one&#x2019;s role in the environment (<xref ref-type="bibr" rid="ref13">Kaplan et al., 2010</xref>), treatment characteristics (<xref ref-type="bibr" rid="ref30">Sherriff et al., 2022</xref>), healthcare processes (<xref ref-type="bibr" rid="ref27">Rollet et al., 2021</xref>), placebo or nocebo effects (<xref ref-type="bibr" rid="ref32">Testa and Rossettini, 2016</xref>), government agencies (<xref ref-type="bibr" rid="ref13">Kaplan et al., 2010</xref>), and cultural beliefs. Occasionally, at a macro-level, they are described as confounders or effect modifiers that are not an outcome of the study, but need to be recognized (and measured) (<xref ref-type="bibr" rid="ref22">Nielsen et al., 2021</xref>; <xref ref-type="bibr" rid="ref28">Sevilla Guerra et al., 2022</xref>).</p>
<p>Recently, through a multi-step process (semi-structured interviews and a Delphi method), the Outcome Measures in Rheumatology (OMERACT) initiative created a consensus definition for contextual factors (<xref ref-type="bibr" rid="ref22">Nielsen et al., 2021</xref>). The principal goal of OMERACT was to identify contextual factors that were relevant for clinical trials. Initially, OMERACT defined a contextual factor as a &#x201C;<italic>variable that is not an outcome of the study, but needs to be recognized (and measured) to understand the study results. This includes potential confounders and effect modifiers</italic>&#x201D; (<xref ref-type="bibr" rid="ref3">Boers et al., 2014</xref>). Through semi-structured interviews and Delphi research, the OMERACT group further qualified contextual factor types (relevant for clinical trials) as: (1) effect modifying (those that modify the treatment effect); (2) outcome influencing (those that predict the prognosis and may confound results); and (3) measurement affecting (those that influence measurement properties such as reliability and validity).</p>
<p>The OMERACT&#x2019;s broad definition is useful for understanding results in a clinical trial, in that it exists within a more historic paradigm that seeks to remove effects rather than enhance them. In this role it fails to resolve some of the confusion associated with the multitudes of ways contextual factors are presently defined (specifically, whether internal and external domains are potentially contextual factors). For example, it does not include qualifiers to improve one&#x2019;s understanding, and provides no guidance as to how clinicians may identify contextual factors within clinical encounters in order to enhance positive and minimize negative effects. Subsequently, the objective of this study was to create a consensus definition of contextual factors to better encapsulate this concept to both guide clinicians in clinical scenarios as well as broaden definitions for researchers.</p>
<p>This study used a virtual nominal group technique (vNGT) (<xref ref-type="bibr" rid="ref25">Potter et al., 2004</xref>), and included researchers and research clinicians from multiple professions who specialized in the study of contextual effects research. We elected to use a vNGT versus a Delphi method because the vNGT allows real time connections between participants (<xref ref-type="bibr" rid="ref25">Potter et al., 2004</xref>), immediate feedback and flexibility when sharing ideas (<xref ref-type="bibr" rid="ref25">Potter et al., 2004</xref>; <xref ref-type="bibr" rid="ref10">Gattrell et al., 2022</xref>), greater discussion in the later stages of consensus development-thus improving refinement of ideas (<xref ref-type="bibr" rid="ref5">Cantrill et al., 2011</xref>), all in a shorter time span (<xref ref-type="bibr" rid="ref25">Potter et al., 2004</xref>). An vNGT has been shown to be viable and potentially advantageous to use online (<xref ref-type="bibr" rid="ref17">Mason et al., 2021</xref>). It has been used previously to identify key implementation factors for COVID-19 vaccination (<xref ref-type="bibr" rid="ref20">Michel et al., 2021</xref>), establish the core components of home-based rehabilitation for survivors of stroke with severe disability (<xref ref-type="bibr" rid="ref9">Fisher et al., 2021</xref>), and selecting intervention content to target barriers and enablers of recognition and response to deteriorating patients (<xref ref-type="bibr" rid="ref31">Smith et al., 2022</xref>). Similar to the OMERACT group, we endeavored to identify a consensus definition that reflects the complexity of contextual factors and describe how contextual factors may influence clinical outcomes, but were also interested in a more detailed set of qualifiers that serve as examples of the key areas of the definition.</p>
</sec>
<sec id="sec2" sec-type="methods">
<title>Methods</title>
<sec id="sec3">
<title>Study design</title>
<p>The mixed methods study used a vNGT (<xref ref-type="bibr" rid="ref25">Potter et al., 2004</xref>). The vNGT was performed in October of 2022. Nominal group techniques are beneficial for identifying problems, exploring solutions and establishing priorities, and encourages contributions from all participants and treats each person equally (<xref ref-type="bibr" rid="ref25">Potter et al., 2004</xref>). The Institutional Review Board of Duke University, Durham, North Carolina, USA, approved the study (ro00111522-INIT-1.0).</p>
</sec>
<sec id="sec4">
<title>Nominal group technique participants</title>
<p>Optimal NGT participants are stated to include five to nine individuals (<xref ref-type="bibr" rid="ref25">Potter et al., 2004</xref>), but values may vary. The first and senior author were responsible for recruitment and reflected the ACCORD guidelines for consensus development (<xref ref-type="bibr" rid="ref34">van Zuuren et al., 2022</xref>). Three drivers primarily drove recruitment: (1) the expertise of the researchers in contextual factors research (determined by publication and/or presentations); (2) the clinical background (when appropriate); and (3) by specialization (e.g., neuroscience, community engagement). The first and senior author also endeavored to balance participants by sex and years of experience. After assembling a short-list of potential participants, the first and senior author invited participation through an email. All potential vNGT members agreed to participate.</p>
</sec>
<sec id="sec5">
<title>Study procedure</title>
<p>Participants were provided with pre-work prior to the vNGT. Each individual was provided with an article (<xref ref-type="bibr" rid="ref25">Potter et al., 2004</xref>) that outlined the vNGT processes and were asked to consider early development of their own versions of a definition for contextual factors.</p>
<p>During the virtual session, a five-stage vNGT process following the protocol by <xref ref-type="bibr" rid="ref25">Potter et al. (2004)</xref> was used (<xref rid="fig1" ref-type="fig">Figure 1</xref>). The virtual session was conducted using Microsoft Zoom (Microsoft Corp, Redmond, WA) and the moderator for the session was a mixed-methods researcher with a contextual factors background and prior experience with vNGT research and moderation.</p>
<fig position="float" id="fig1">
<label>Figure 1</label>
<caption><p>The Five Stage Process of a Virtual Nominal Group Technique according to <xref ref-type="bibr" rid="ref25">Potter et al. (2004)</xref>.</p></caption>
<graphic xlink:href="fpsyg-14-1178560-g001.tif"/>
</fig>
<p><italic>Stage one</italic> (Introduction and Explanation): An introduction and welcome to all participants with an explanation of the purpose and procedure of the workshop.</p>
<p><italic>Stage two</italic> (Silent Idea Generation): The question was introduced to the participants: &#x201C;What is a working definition of contextual factors&#x201D;? All participants were asked to create a list of ideas that come to mind when considering the question and to place these ideas on a shared Google document. During this stage, all participants were asked not to consult or discuss ideas with each other. A total of 10&#x2009;min was provided for each participant to create his or her selected definitions.</p>
<p><italic>Stage three</italic> (Sharing Ideas): During Stage three, each participant introduced their definitions that were recorded on the google documents. This document was shared on the screen so that all participants can see the list in real time. This stage continued in a round robin format until all ideas had been presented. No debate or discussion occurred at this stage.</p>
<p><italic>Stage four</italic> (Group Discussion): Participants were invited to seek verbal explanation or further details about any ideas that were produced during stage three. The moderator ensured that each person was able to contribute and that all ideas were discussed without spending too long on a single idea. At this stage, participants were able to suggest new items for discussion or combining of items to modify the current list. Each participant &#x201C;owned&#x201D; each definition and edited the definition only if they agreed on the change requested.</p>
<p>Unique to this vNGT, participants had up to 1&#x2009;week to modify or delete their own contributions or request edits to another definition that they did not generate. We elected to provide additional time to edit each person&#x2019;s definition, since the concept is complex and since there were a variety of definitions presented in Stage two and three, which were further discussed and modified in Stage four.</p>
<p><italic>Stage five</italic> (Voting): During stage five, and after the week of modifying or deleting their own contributions, vNGT participants were allowed to &#x201C;rank order&#x201D; the definitions generated during stage four. Rank ordering was performed using a Qualtrics survey and a &#x201C;ranking&#x201D; function. In this survey, each NGT participant ranked all 12 definitions from 1 (top choice) to 12 (lowest choice).</p>
<p>Modifications of a five round NGT are not uncommon and may be warranted when working with complex populations or topics that require maturation before final evaluation (<xref ref-type="bibr" rid="ref19">McMillan et al., 2016</xref>). If consensus voting does not identify a clear ranked winner, a sixth round, which includes re-voting on the top ranked choices, can be implemented to assure a true consensus choice (<xref ref-type="bibr" rid="ref25">Potter et al., 2004</xref>; <xref ref-type="bibr" rid="ref19">McMillan et al., 2016</xref>). Our vNGT used a sixth round of voting to identify a clear consensus definition.</p>
</sec>
</sec>
<sec id="sec6" sec-type="results">
<title>Results</title>
<sec id="sec7">
<title>Participants characteristics</title>
<p>The vNGT included 10 individuals with clinical/research backgrounds in rehabilitation (chiropractic, osteopathy, physical therapy, or occupational therapy), clinical psychology, medicine, and nursing. Advanced research training included community engagement, molecular biology, nursing science, neurobiology, neuroscience, placebo/nocebo, rehabilitation medicine, and social determinants of health (<xref rid="tab1" ref-type="table">Table 1</xref>). The vNGT participants averaged 19 publications on contextual factors, and represented 4 countries across two continents.</p>
<table-wrap position="float" id="tab1">
<label>Table 1</label>
<caption><p>Virtual nominal group technique voting participants&#x2019; backgrounds.</p></caption>
<table frame="hsides" rules="groups">
<thead>
<tr>
<th align="left" valign="top">Clinical background</th>
<th align="left" valign="top">Research training and background</th>
<th align="left" valign="top">Location</th>
<th align="center" valign="top">Number of publications directly or indirectly involving contextual factors</th>
</tr>
</thead>
<tbody>
<tr>
<td align="left" valign="top">Chiropractic</td>
<td align="left" valign="top">Anatomical sciences and neurobiology<break/>Neuroscience with a research focus in physiological and pain-related mechanisms</td>
<td align="left" valign="top">United States</td>
<td align="center" valign="top">30</td>
</tr>
<tr>
<td align="left" valign="top">Medical physician/neurophysiologist</td>
<td align="left" valign="top">Neuroscience</td>
<td align="left" valign="top">United States</td>
<td align="center" valign="top">10</td>
</tr>
<tr>
<td align="left" valign="top">None</td>
<td align="left" valign="top">Molecular biology, musculoskeletal heath</td>
<td align="left" valign="top">UK</td>
<td align="center" valign="top">9</td>
</tr>
<tr>
<td align="left" valign="top">Nursing</td>
<td align="left" valign="top">Nursing science</td>
<td align="left" valign="top">Italy</td>
<td align="center" valign="top">15</td>
</tr>
<tr>
<td align="left" valign="top">Occupational therapy</td>
<td align="left" valign="top">Community-based mental health service delivery models, sensory processing and participation</td>
<td align="left" valign="top">United States</td>
<td align="center" valign="top">19</td>
</tr>
<tr>
<td align="left" valign="top">Osteopathy</td>
<td align="left" valign="top">Cognitive science</td>
<td align="left" valign="top">Malta</td>
<td align="center" valign="top">10</td>
</tr>
<tr>
<td align="left" valign="top">Physiotherapist</td>
<td align="left" valign="top">Placebo and nocebo effects associated with contextual factors</td>
<td align="left" valign="top">Italy</td>
<td align="center" valign="top">18</td>
</tr>
<tr>
<td align="left" valign="top">Physiotherapist</td>
<td align="left" valign="top">Rehabilitation Science</td>
<td align="left" valign="top">United States</td>
<td align="center" valign="top">21</td>
</tr>
<tr>
<td align="left" valign="top">Psychologist</td>
<td align="left" valign="top">Neuroscience</td>
<td align="left" valign="top">Italy</td>
<td align="center" valign="top">34</td>
</tr>
<tr>
<td align="left" valign="top">Psychologist</td>
<td align="left" valign="top">Behavioral intervention, development and implementation, and mediators and moderators of intervention effects</td>
<td align="left" valign="top">United States</td>
<td align="center" valign="top">21</td>
</tr>
</tbody>
</table>
</table-wrap>
</sec>
<sec id="sec8">
<title>Findings of the nominal group technique</title>
<p>Stage two generated 14 definitions of contextual factors (<xref rid="tab2" ref-type="table">Table 2</xref>). Seven vNGT participants submitted one definition, whereas two participants submitted two definitions and one submitted three. Consistent domains included internal and external factors, which influenced outcomes associated with any of the treatments provided. Stage four refined the definitions through audience (clinicians and researchers) discussion and the need for a single consensus definition including qualifiers that help define the definition and how contextual factors may influence outcomes.</p>
<table-wrap position="float" id="tab2">
<label>Table 2</label>
<caption><p>Initial contextual factor definitions (upon completion of stage two).</p></caption>
<table frame="hsides" rules="groups">
<thead>
<tr>
<th align="left" valign="middle">Definition number</th>
<th align="left" valign="middle">Definition</th>
</tr>
</thead>
<tbody>
<tr>
<td align="left" valign="top">One</td>
<td align="left" valign="top">Contextual factors are the context elements always presented during the patient&#x2019;s interaction with the healthcare provider. They are involved in the placebo or nocebo effects and can influence the therapeutic outcomes. Some examples of them are: (1) the clinician&#x2019;s features (e.g., professionalism, mindset and appearance), (2) the patient&#x2019;s features (e.g., beliefs, previous experiences and expectations), (3) the patient clinician relationship (e.g., the words, gestures and behavior), (4) the characteristics of the treatment (e.g., the rituality, the invasiveness and the marketing), and (5) the overall healthcare setting (e.g., furniture, the architectural design and the overall impression of the clinic).</td>
</tr>
<tr>
<td align="left" valign="top">Two</td>
<td align="left" valign="top">Contextual factors are elements of the context that accompanies the administration of a treatment (active or placebo). These elements can change the effectiveness of the treatment in a positive (placebo effect) or negative (nocebo effect) way. Contextual factors can be labeled as internal, external or relational.<break/>Internal factors consist of memories, emotions, expectations and psychological and genetic characteristics of the patient involved in the therapy.<break/>External factors include the physical aspects of therapy, such as the kind of treatment (e.g., pharmacological or manual) and the place in which the treatment is delivered.<break/>Relational factors are represented by all the social cues that characterize the patient-physiotherapist relationship, such as the verbal information that the physiotherapist gives to the patient, the communication style or the body language.</td>
</tr>
<tr>
<td align="left" valign="top">Three</td>
<td align="left" valign="top">Contextual factors are past and present environmental cues perceived by individuals either consciously or unconsciously that have the capacity to alter the prediction of future events including outcomes of therapeutic encounters</td>
</tr>
<tr>
<td align="left" valign="top">Four</td>
<td align="left" valign="top">Contextual factors are mechanisms through which some treatment effects occur including; factors related to the patient such as their expectations and beliefs; the therapist such as their personality, preferences, and beliefs, and the interaction between the therapist and the patient such as the strength of their relationship. Contextual factors are the mechanisms through which placebo and nocebo effects occur; however, clinically, contextual factors reflect mechanisms underlying treatment effects as opposed to placebo/nocebo effects. Contextual factors do not result in general, non-specific effects of interventions. Rather, contextual factors result in specific effects dependent on the individual beliefs of the patient and provider for a specific intervention.</td>
</tr>
<tr>
<td align="left" valign="top">Five</td>
<td align="left" valign="top">Contextual factors are a critical component of the ecological niche surrounding the delivery of care. They are a broad range of factors/mechanisms that can positively or negatively influence the process of care. These include intra- and interpersonal factors (practitioner&#x2019;s belief system and style of practice, patient&#x2019;s expectations, prior experiences of care and predictive responses to care, communication styles, therapeutic alliance), environmental factors (clinical setting, online presence, organizational value system, communication), cultural/social factors (word of mouth/referral based on recommendations by friends and family, role of the practitioner/organization in the community).</td>
</tr>
<tr>
<td align="left" valign="top">Six</td>
<td align="left" valign="top">Contextual factors are physical, psychological and social elements that characterize the therapeutic encounter with the patient. They are actively interpreted by the patient and are capable of eliciting expectations, memories and emotions that, in turn, can influence the health-related outcome, producing placebo or nocebo effects.</td>
</tr>
<tr>
<td align="left" valign="top">Seven</td>
<td align="left" valign="top">Contextual factors are cues or information of the clinical or experimental context that accompanies the administration of a treatment. These elements are perceived and actively interpreted by the patient&#x2019;s brain</td>
</tr>
<tr>
<td align="left" valign="top">Eight</td>
<td align="left" valign="top">Contextual factors present during clinical care are perceived characteristics of the therapeutic environment considered important by patients and that curate a sense of what the encounter means which can modulate patient expectations as to what the likely outcomes might be</td>
</tr>
<tr>
<td align="left" valign="top">Nine</td>
<td align="left" valign="top">The Contextual factors represent the whole atmosphere around the therapy; the context that accompanies any healthcare treatment.</td>
</tr>
<tr>
<td align="left" valign="top">Ten</td>
<td align="left" valign="top">Contextual factors constitute implicitly or explicitly perceived information used by individuals to estimate/predict future individual states. Such estimations can influence central sensory processing in such a way as to make such estimated sensory states true for the individual.</td>
</tr>
<tr>
<td align="left" valign="top">Eleven</td>
<td align="left" valign="top">The context of an action includes all micro, meso, and macro environmental factors (i.e., natural, sensorial, temporal, built, economic, political, cultural, social) and personal factors of individuals, groups and populations involved in the expression of the action being analyzed.</td>
</tr>
<tr>
<td align="left" valign="top">Twelve</td>
<td align="left" valign="top">Contextual factors are everything verbal and non-verbal outside of the therapeutic intervention that is experienced by the patient in relation to personal and environmental interaction during the clinical encounter. These include internal (patient expectations, emotions, etc.), external (facility, treatment room etc.) and relational factors (clinician-patient interaction, staff-patient interaction, etc.)</td>
</tr>
<tr>
<td align="left" valign="top">Thirteen</td>
<td align="left" valign="top">Contextual factors are the context in which any therapeutic treatment occurs and iteratively influence the trajectory of any health-related outcome. These include the current environment as well as current and historical physical, emotional, social, and cultural experiences that affect both patient and provider behavior, interactions, and expectations throughout the course of care.</td>
</tr>
<tr>
<td align="left" valign="top">Fourteen</td>
<td align="left" valign="top">Contextual factors are the external factors around a treatment. Any treatment is given not in a vacuum. The clinical setting, the patient-clinician including patient-caregiver-clinician interactions, occur within a specific context (where, when, and how). The contextual factors are external factors. Psychosocial factors are internal factors, which complement the contextual factors.</td>
</tr>
</tbody>
</table>
</table-wrap>
<p>At the end of Stage four (consolidation of ideas), there were 12 definitions that were rank ordered (<xref rid="tab3" ref-type="table">Table 3</xref>). Three definitions were clearly ranked higher than (<xref rid="tab4" ref-type="table">Table 4</xref>) the remaining nine with the majority (80%) of the vNGT selecting these choices as one of the top three selections. These three were similar in content and scope and finished with mean &#x201C;ranked&#x201D; scores of 3.0, 3.7 and 3.8, respectively. Following a further poll of the group it was felt that it was necessary to vote again (Round six), but to only include the three aforementioned definitions. Upon re-vote, one clear winner was identified.</p>
<table-wrap position="float" id="tab3">
<label>Table 3</label>
<caption><p>Modified contextual factor definitions (upon completion of stage four).</p></caption>
<table frame="hsides" rules="groups">
<thead>
<tr>
<th align="left" valign="middle">Definition Number</th>
<th align="left" valign="middle">Definition</th>
</tr>
</thead>
<tbody>
<tr>
<td align="left" valign="top">One</td>
<td align="left" valign="top">Contextual factors (CFs) are components of the therapeutic encounter whereby interventions, medications, pharmacological and nonpharmacological treatments are given. CFs encompass the patient and provider personal (i.e., race/ethnicity and expectations), historical (i.e., clinical history and prior experiences), cultural (i.e., social norms, spirituality/religion and power differentials), environmental (i.e., settings and rituals), physical (i.e., sensorial perception and clinical procedures), and rhetorical (i.e., verbal and non-verbal elements of communication) dimensions around the therapeutic encounter and the patient-clinician interaction influencing moderators/mediators of therapeutic mechanisms and the response to any interventions/treatments and ultimately, the overall clinical outcomes. CFs can change the effectiveness of the treatment in a positive (placebo effect) or negative (nocebo effect) way.</td>
</tr>
<tr>
<td align="left" valign="top">Two</td>
<td align="left" valign="top">Contextual factors (CFs) are components of the therapeutic encounter whereby interventions, medications, pharmacological and nonpharmacological treatments are given. CFs encompass the patient and provider personal (e.g., race/ethnicity, genetic variables, expectations, values and preference), historical (e.g., clinical history, prior experiences), cultural (e.g., social norms, spirituality/religion and power differentials), environmental (e.g., settings and rituals), physical (e.g., sensorial perception, clinical examination and modalities in which the therapy is delivered), and rhetorical (e.g., verbal and non-verbal communication) dimensions around the therapeutic encounter and the patient-clinician interaction influencing moderators/mediators of therapeutic mechanisms and the response to any interventions/treatments and ultimately, the overall clinical outcomes. CFs can change the effectiveness of the treatment in a positive (placebo effect) or negative (nocebo effect) way.</td>
</tr>
<tr>
<td align="left" valign="top">Three</td>
<td align="left" valign="top">Contextual factors are mechanisms through which some treatment effects occur including; factors related to the patient such as their expectations and beliefs; the therapist such as their personality, preferences, and beliefs, and the interaction between the therapist and the patient such as the strength of their relationship. Contextual factors are the mechanisms through which placebo and nocebo effects occur; however, clinically, contextual factors reflect mechanisms underlying treatment effects as opposed to placebo/nocebo effects. Contextual factors do not result in general, non-specific effects of interventions. Rather, contextual factors result in specific effects dependent on the individual beliefs of the patient and provider for a specific intervention.</td>
</tr>
<tr>
<td align="left" valign="top">Four</td>
<td align="left" valign="top">Contextual factors are a critical component of the ecological therapeutic niche. They are a broad range of factors that can positively or negatively influence the process of care. These include intra- and interpersonal factors (practitioner&#x2019;s belief system and style of practice, patient&#x2019;s expectations, prior experiences of care and predictive responses to care, communication styles, therapeutic alliance), environmental factors (clinical setting, online presence, organizational value system, communication), cultural/social factors (word of mouth/referral based on recommendations by friends and family, role of the practitioner/organization in the community).</td>
</tr>
<tr>
<td align="left" valign="top">Five</td>
<td align="left" valign="top">Contextual factors are physical, psychological and social elements that characterize the therapeutic encounter with the patient. They are actively interpreted by the patient and are capable of eliciting expectations, memories and emotions that, in turn, can influence the health-related outcome, producing placebo or nocebo effects.</td>
</tr>
<tr>
<td align="left" valign="top">Six</td>
<td align="left" valign="top">Contextual factors are cues or information of the clinical or experimental context that accompanies the administration of a treatment. These elements are perceived and actively interpreted by the patient&#x2019;s brain.</td>
</tr>
<tr>
<td align="left" valign="top">Seven</td>
<td align="left" valign="top">Contextual factors represent the whole atmosphere around the therapy; the context that accompanies any healthcare treatment.</td>
</tr>
<tr>
<td align="left" valign="top">Eight</td>
<td align="left" valign="top">Contextual factors (CFs) are components of all therapeutic encounters and may constitute the entirety of the perceived effects of the intervention itself or be additive to effects of interventions such as pharmacological and nonpharmacological treatments. CFs are perceived cues that affect both the patient and practitioner and can arise from experiences and immediate dynamics within the encounter, or a combination of both. CFs fall into broad categories that can include patient characteristics, practitioner characteristics, treatment characteristics, characteristics of the dynamic between the patient and practitioner and characteristics of the setting within which the encounter is being delivered. CFs can be complexly interwoven in the patients and practitioners experience so as to influence what patients and practitioners expect the outcome of the encounter to be. Through such conscious and unconscious expectations, involving a range of specific neurological pathways, CFs can directly impact (both positively and negatively) symptoms and characteristics associated with the presenting condition. The proportion of clinical effects observed associated with CFs can vary from large to small depending on the characteristics of the patient, practitioner, condition and intervention.</td>
</tr>
<tr>
<td align="left" valign="top">Nine</td>
<td align="left" valign="top">Contextual factors are integral components of a therapeutic encounter and can include environmental factors (e.g., natural, sensorial, temporal, built, economic, political, cultural, social) and personal factors of all individuals involved (e.g., physical, mental, social, cultural) in the therapeutic encounter. Some contextual factors are modifiable and can be targeted in intervention to effect change to personal factors.</td>
</tr>
<tr>
<td align="left" valign="top">Ten</td>
<td align="left" valign="top">Contextual factors are everything verbal and non-verbal outside of the therapeutic intervention that is experienced by the patient in relation to personal and environmental interaction during the clinical encounter. These include internal (e.g., patient expectations, emotions, cultural), external (e.g., facility ambience, environment) and relational (e.g., clinician/staff-patient interaction, social, physical, historical) factors that impact moderators/mediators of therapeutic outcomes.</td>
</tr>
<tr>
<td align="left" valign="top">Eleven</td>
<td align="left" valign="top">Contextual factors are moderating/mediating components of the therapeutic encounter that influence the trajectory of a health-related outcome. These include the current therapeutic environment as well as current and historical physical, emotional, social, and cultural experiences that affect both patient and provider behavior, interactions, and expectations throughout the course of care.</td>
</tr>
<tr>
<td align="left" valign="top">Twelve</td>
<td align="left" valign="top">Contextual factors are components of the therapeutic encounter whereby interventions, medications, pharmacological and nonpharmacological treatments are given. Contextual factors encompass the patient and provider personal (e.g., race/ethnicity, expectations, values and preference), historical (e.g., clinical history, prior experiences), cultural (e.g., social norms, spirituality/religion and power differentials), environmental (e.g., settings and rituals), physical (e.g., sensorial perception, and clinical examination), and rhetorical (e.g., verbal and non-verbal communication) dimensions around the therapeutic encounter and the patient-clinician interaction influencing moderators/mediators of therapeutic mechanisms and the response to any interventions/treatments and ultimately, the overall clinical outcomes.</td>
</tr>
</tbody>
</table>
</table-wrap>
<table-wrap position="float" id="tab4">
<label>Table 4</label>
<caption><p>Top Three Ranked Contextual Factor Definitions (Upon Completion of Stage Five).</p></caption>
<table frame="hsides" rules="groups">
<thead>
<tr>
<th align="left" valign="top">Rank order</th>
<th align="left" valign="top">Definition</th>
<th align="center" valign="top">Average score/median</th>
</tr>
</thead>
<tbody>
<tr>
<td align="left" valign="top">First</td>
<td align="left" valign="top">Contextual factors are components of the therapeutic encounter whereby interventions, medications, pharmacological and nonpharmacological treatments are given. Contextual factors encompass the patient and provider personal (e.g., race/ethnicity, expectations, values and preference), historical (e.g., clinical history, prior experiences), cultural (e.g., social norms, spirituality/religion and power differentials), environmental (e.g., settings and rituals), physical (e.g., sensorial perception, and clinical examination), and rhetorical (e.g., verbal and non-verbal communication) dimensions around the therapeutic encounter and the patient-clinician interaction influencing moderators/mediators of therapeutic mechanisms and the response to any interventions/treatments and ultimately, the overall clinical outcomes.</td>
<td align="center" valign="top">3.0/2.0</td>
</tr>
<tr>
<td align="left" valign="top">Second</td>
<td align="left" valign="top">Contextual factors (CFs) are components of all therapeutic encounters and may constitute the entirety of the perceived effects of the intervention itself or be additive to effects of interventions such as pharmacological and nonpharmacological treatments. CFs are perceived cues that affect both the patient and practitioner and can arise from past experiences and immediate dynamics within the encounter, or a combination of both. CFs fall into broad categories that can include patient characteristics, practitioner characteristics, treatment characteristics, characteristics of the dynamic between the patient and practitioner and characteristics of the setting within which the encounter is being delivered. CFs can be complexly interwoven in the patients and practitioners experience so as to influence what patients and practitioners expect the outcome of the encounter to be. Through such conscious and unconscious expectations, involving a range of specific neurological pathways, CFs can directly impact (both positively and negatively) symptoms and characteristics associated with the presenting condition. The proportion of clinical effects observed associated with CFs can vary from large to small depending on the characteristics of the patient, practitioner, condition and intervention.</td>
<td align="center" valign="top">3.7/3.0</td>
</tr>
<tr>
<td align="left" valign="top">Third</td>
<td align="left" valign="top">Contextual factors (CFs) are components of the therapeutic encounter whereby interventions, medications, pharmacological and nonpharmacological treatments are given. CFs encompass the patient and provider personal (e.g., race/ethnicity, genetic variables, expectations, values and preference), historical (e.g., clinical history, prior experiences), cultural (e.g., social norms, spirituality/religion and power differentials), environmental (e.g., settings and rituals), physical (e.g., sensorial perception, clinical examination and modalities in which the therapy is delivered), and rhetorical (e.g., verbal and non-verbal communication) dimensions around the therapeutic encounter and the patient-clinician interaction influencing moderators/mediators of therapeutic mechanisms and the response to any interventions/treatments and ultimately, the overall clinical outcomes. CFs can change the effectiveness of the treatment in a positive (placebo effect) or negative (nocebo effect) way.</td>
<td align="center" valign="top">3.8 / 3.0</td>
</tr>
</tbody>
</table>
</table-wrap>
<sec id="sec9">
<title>Final definition</title>
<p>Contextual factors (CFs) are components of all therapeutic encounters and may constitute the entirety of the perceived effects of the intervention itself or be additive to effects of interventions such as pharmacological and nonpharmacological treatments. CFs are perceived cues that affect both the patient and practitioner and can arise from previous experiences and immediate dynamics within the encounter, or a combination of both. CFs fall into broad categories that can include patient characteristics, practitioner characteristics, treatment characteristics, characteristics of the dynamic between the patient and practitioner and characteristics of the setting within which the encounter is being delivered. CFs can be complexly interwoven in the patients and practitioners experience so as to influence what patients and practitioners expect the outcome of the encounter to be. Through such conscious and unconscious expectations, involving a range of specific neurological pathways, CFs can directly influence (both positively and negatively) symptoms and characteristics associated with the presenting condition. The proportion of clinical effects observed associated with CFs can vary from large to small depending on the characteristics of the patient, practitioner, condition and intervention.</p>
</sec>
</sec>
</sec>
<sec id="sec10" sec-type="discussions">
<title>Discussion</title>
<p>The goal of the study was to develop a consensus-derived definition of contextual factors. The study methodology used an vNGT, which is beneficial for identifying problems (<xref ref-type="bibr" rid="ref35">Young et al., 2021</xref>), exploring solutions and establishing priorities, and providing a meaningful and economical method of soliciting contributions from all participants (<xref ref-type="bibr" rid="ref25">Potter et al., 2004</xref>). Our final consensus selection reflects the complexity of a definition of contextual factors and includes: (1) an overall definition, (2) qualifiers that serve as examples of the key areas of the definition and (3) how contextual factors may influence clinical outcomes. We feel this harmonized definition will improve the understanding of contextual factors and will help clinicians recognize their potential role in moderating and/or mediating these factors to positively impact clinical outcomes. Further, we feel the findings may also improve interpretation of research and deserve additional discussion.</p>
<p>The vNGT participants identified the influence of contextual factors as mediators, moderators, or confounding variables and felt that contextual factors included both internal and external factors. These fell into broad categories that included patient characteristics, practitioner characteristics, treatment characteristics, characteristics of the dynamic between the patient and practitioner and characteristics of the setting within which the encounter is being delivered. This suggests that <italic>who</italic> is enrolled in a study, <italic>who</italic> provides care in a study, and <italic>where</italic> that study is performed may influence clinical outcomes. The OMERACT group (<xref ref-type="bibr" rid="ref22">Nielsen et al., 2021</xref>) defined contextual factors as personal factors, disease-related factors, and environmental factors, each with a possibility of being effect modifying, outcome influencing, and measurement affecting (<xref ref-type="bibr" rid="ref22">Nielsen et al., 2021</xref>). Similarities between the two definitions include the multidimensional aspect of the definitions and the role of contextual factors in influencing clinical outcomes. Differences include the more granular aspects of the vNGT definition, less explicitness in its effect-modifying role [which is well detailed in the OMERACT example (<xref ref-type="bibr" rid="ref22">Nielsen et al., 2021</xref>)] and the omission of disease-related factors in the vNGT definition.</p>
<p>Our initial set of 14 definitions identified a number of common elements associated with contextual factors. The biggest differences across initial definitions included whether contextual factors were considered as placebo/nocebo effects, whether the factors were actively or passively perceived (or both), and whether contextual factors were considered moderators of treatment (e.g., age, sex, socioeconomic status), mediators of treatment (e.g., self-efficacy, fear, psychological mood) or both. Discussion during stage three highlighted the inconsistent domains involved in the role of cultural versus political versus power imbalances, whether contextual factors were a measurable mechanism, whether placebo/nocebo effects were a necessity within the definition, if a contextual factor was a &#x201C;nonspecific&#x201D; finding, and its role as a prognostic mediator/moderator. Thus, the emerging findings mirror the heterogeneity of conceptual definition and the variability of dimensions associated with contextual factors reported in the literature (<xref ref-type="bibr" rid="ref18">McLaren and Hawe, 2005</xref>; <xref ref-type="bibr" rid="ref13">Kaplan et al., 2010</xref>; <xref ref-type="bibr" rid="ref32">Testa and Rossettini, 2016</xref>; <xref ref-type="bibr" rid="ref23">Nielsen et al., 2019</xref>, <xref ref-type="bibr" rid="ref22">2021</xref>; <xref ref-type="bibr" rid="ref27">Rollet et al., 2021</xref>; <xref ref-type="bibr" rid="ref28">Sevilla Guerra et al., 2022</xref>; <xref ref-type="bibr" rid="ref30">Sherriff et al., 2022</xref>). Our work acknowledged and established an initial synthesis of these complex and important domains, which may in turn be fruitful to consider in future work.</p>
<p>Despite a wide range of clinical backgrounds and research training expertise, we were pleased with the collaborative nature of our vNGT. With appropriate pre-work and judicious use of time (<xref ref-type="bibr" rid="ref25">Potter et al., 2004</xref>), we were able to consolidate many disparate initial thoughts to common themes within the two-hour timeframe. When properly employed, consensus agreement methods create structured environments for which experts are prompted to give the best available information, allowing solutions to problems that may remain otherwise unsolved (<xref ref-type="bibr" rid="ref8">Fink et al., 1984</xref>). This requires the process to be deliberately inclusive, participatory, collaborative, and cooperative, with an ultimate goal of a final consensus agreement (<xref ref-type="bibr" rid="ref2">Black et al., 1999</xref>). A fundamental element of this methodology is that it does not require all participants to agree on all topics (it implies only general agreement) nor does it assure unanimity.</p>
<p>At the end of stage four, vNGT participants were allocated 1&#x2009;week to modify their own definitions of contextual factors and then were given a 48-h window to rank order the final definitions. Eventually, a sixth round was deemed necessary to further separate three competing definitions. During stage four, notable harmonizing occurred across each of the definitions, especially our first goal of obtaining an overall definition. A majority also agreed that contextual factors moderated or mediated clinical outcomes and compared to the initial set of definitions, most included qualifying statements with the definitions as well. The qualifying statements, such as patient and provider personal, historical, cultural, environmental, physical, and rhetorical dimensions around the therapeutic encounter and the patient-clinician interaction, are what separates our definition from that of the OMERACT group (<xref ref-type="bibr" rid="ref22">Nielsen et al., 2021</xref>).</p>
<sec id="sec11">
<title>Limitations</title>
<p>Although this study provided new insights into contextual factors&#x2019; definition, some limitations are worth mentioning. Firstly, although we exceeded the recommended panel size of an NGT, we involved a small sample of participants from a restricted number of healthcare fields, possibly leaving others unrepresented (e.g., midwifery, speech therapy, and optometry). Regardless, we ensured adequate representativeness of contextual factors experts in our vNGT by balancing the number of males and females (M: <italic>F</italic>&#x2009;=&#x2009;6:4) and including clinicians and clinical researchers from more than one country (<xref ref-type="bibr" rid="ref16">Manera et al., 2019</xref>). Secondly, compared to conducting an in-person NGT, using a virtual Zoom platform could have produced a limited interaction between participants with potentially diverging opinions, thus introducing bias. Nevertheless, the limited time and resource requirements of the vNGT, together with the presence of an experienced moderator, guaranteed a satisfactory quality of the participatory process, considering all participants&#x2019; views equally and minimizing any dominant effects (<xref ref-type="bibr" rid="ref16">Manera et al., 2019</xref>). Thirdly, our vNGT participants had a predominant musculoskeletal background. Lastly, we should have compared the definition of contextual factors obtained with our vNGT with other methods (e.g., Delphi, brainstorming) to evaluate their similarities and differences. However, we deliberately used the vNGT because it represents a suitable consensus method to reach an agreement on a single and complex topic among the participants (<xref ref-type="bibr" rid="ref16">Manera et al., 2019</xref>).</p>
</sec>
</sec>
<sec id="sec12" sec-type="conclusions">
<title>Conclusion</title>
<p>Our study, involving a panel of international experts with a majority musculoskeletal background, offered the opportunity to identify a definition of contextual factors, find their qualifiers and understand their impact on the therapeutic outcome. This initial definition may help clinicians and researchers embrace the complexity that underlies the construct of contextual factors. We acknowledge different opinions can coexist; we present our definition as a starting point for future studies on the topic. A Delphi method may be a useful approach to determine consensus across a broader background of individuals and is a recommended follow-up step to this research.</p>
</sec>
<sec id="sec13" sec-type="data-availability">
<title>Data availability statement</title>
<p>The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.</p>
</sec>
<sec id="sec14">
<title>Ethics statement</title>
<p>The studies involving human participants were reviewed and approved by The Institutional Review Board of Duke University, Durham, North Carolina, USA, approved the study (ro00111522-INIT-1.0). The patients/participants provided their written informed consent to participate in this study.</p>
</sec>
<sec id="sec15">
<title>Author contributions</title>
<p>CC and GR contributed to the conception and design of the study and wrote the first draft of the manuscript. AB, JAB, JEB, EC, LC, JE, DN, AP, WR, and JV wrote sections of the manuscript. All authors contributed to manuscript revision, read and approved the submitted version.</p>
</sec>
<sec id="sec16" sec-type="funding-information">
<title>Funding</title>
<p>This was a NIH U24 supported research study [1U24AT011969-01, Force-Based Manipulation network (ForceNet)]; Administering institutes or centers National Center for Complementary and Integrative Health, <ext-link xlink:href="https://reporter.nih.gov/search/Hq4YC-ZDk0yDq2PgxIHgVA/project-details/10450926" ext-link-type="uri">https://reporter.nih.gov/search/Hq4YC-ZDk0yDq2PgxIHgVA/project-details/10450926</ext-link>. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.</p>
</sec>
<sec id="conf1" sec-type="COI-statement">
<title>Conflict of interest</title>
<p>GR leads education programmes on placebo, nocebo effects and contextual factors in healthcare to under- and post-graduate students along with private CPD courses. CC receives honoraria from book sales and continuing education courses, and is a consultant for Revenite and the Hawkins Foundation. None of the honoraria or consulting work has a competing interest with the work provided in this paper.</p>
<p>The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.</p>
</sec>
<sec id="sec100" sec-type="disclaimer">
<title>Publisher&#x2019;s note</title>
<p>All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.</p>
</sec>
</body>
<back>
<ref-list>
<title>References</title>
<ref id="ref1"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Bishop</surname> <given-names>M. D.</given-names></name> <name><surname>Mintken</surname> <given-names>P. E.</given-names></name> <name><surname>Bialosky</surname> <given-names>J. E.</given-names></name> <name><surname>Cleland</surname> <given-names>J. A.</given-names></name></person-group> (<year>2013</year>). <article-title>Patient expectations of benefit from interventions for neck pain and resulting influence on outcomes</article-title>. <source>J. Orthop. Sports Phys. Ther.</source> <volume>43</volume>, <fpage>457</fpage>&#x2013;<lpage>465</lpage>. doi: <pub-id pub-id-type="doi">10.2519/jospt.2013.4492</pub-id>, PMID: <pub-id pub-id-type="pmid">23508341</pub-id></citation></ref>
<ref id="ref2"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Black</surname> <given-names>N.</given-names></name> <name><surname>Murphy</surname> <given-names>A.</given-names></name> <name><surname>Lamping</surname> <given-names>D.</given-names></name> <name><surname>McKee</surname> <given-names>M.</given-names></name> <name><surname>Sanderson</surname> <given-names>C.</given-names></name> <name><surname>Askham</surname> <given-names>J.</given-names></name> <etal/></person-group>. (<year>1999</year>). <article-title>Consensus development methods: a review of best practice in creating clinical guidelines</article-title>. <source>J. Health Serv. Res. Policy</source> <volume>4</volume>, <fpage>236</fpage>&#x2013;<lpage>248</lpage>. doi: <pub-id pub-id-type="doi">10.1177/135581969900400410</pub-id></citation></ref>
<ref id="ref3"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Boers</surname> <given-names>M.</given-names></name> <name><surname>Kirwan</surname> <given-names>J. R.</given-names></name> <name><surname>Wells</surname> <given-names>G.</given-names></name> <name><surname>Beaton</surname> <given-names>D.</given-names></name> <name><surname>Gossec</surname> <given-names>L.</given-names></name> <name><surname>d&#x2019;Agostino</surname> <given-names>M. A.</given-names></name> <etal/></person-group>. (<year>2014</year>). <article-title>Developing core outcome measurement sets for clinical trials: OMERACT filter 2.0</article-title>. <source>J. Clin. Epidemiol.</source> <volume>67</volume>, <fpage>745</fpage>&#x2013;<lpage>753</lpage>. doi: <pub-id pub-id-type="doi">10.1016/j.jclinepi.2013.11.013</pub-id>, PMID: <pub-id pub-id-type="pmid">24582946</pub-id></citation></ref>
<ref id="ref5"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Cantrill</surname> <given-names>J. A.</given-names></name> <name><surname>Sibbald</surname> <given-names>B.</given-names></name> <name><surname>Buetow</surname> <given-names>S.</given-names></name></person-group> (<year>2011</year>). <article-title>The Delphi and nominal group techniques in health services research</article-title>. <source>Int. J. Pharm. Pract.</source> <volume>4</volume>, <fpage>67</fpage>&#x2013;<lpage>74</lpage>. doi: <pub-id pub-id-type="doi">10.1111/j.2042-7174.1996.tb00844.x</pub-id></citation></ref>
<ref id="ref6"><citation citation-type="web"><person-group person-group-type="author"><collab id="coll1">Centers of Disease Control and Prevention</collab></person-group>. (<year>2012</year>) Principles of Epidemiology, Lesson 1, Section 9. <source>Natural history and Spectrum of disease</source>. <comment>Available at:</comment> <ext-link xlink:href="https://www.cdc.gov/csels/dsepd/ss1978/lesson1/section9.html" ext-link-type="uri">https://www.cdc.gov/csels/dsepd/ss1978/lesson1/section9.html</ext-link> (Accessed December 2022).</citation></ref>
<ref id="ref7"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Eklund</surname> <given-names>A.</given-names></name> <name><surname>De Carvalho</surname> <given-names>D.</given-names></name> <name><surname>Pag&#x00E9;</surname> <given-names>I.</given-names></name> <name><surname>Wong</surname> <given-names>A.</given-names></name> <name><surname>Johansson</surname> <given-names>M. S.</given-names></name> <name><surname>Pohlman</surname> <given-names>K. A.</given-names></name> <etal/></person-group>. (<year>2019</year>). <article-title>Expectations influence treatment outcomes in patients with low back pain. A secondary analysis of data from a randomized clinical trial</article-title>. <source>Eur. J. Pain</source> <volume>23</volume>, <fpage>1378</fpage>&#x2013;<lpage>1389</lpage>. doi: <pub-id pub-id-type="doi">10.1002/ejp.1407</pub-id>, PMID: <pub-id pub-id-type="pmid">31034102</pub-id></citation></ref>
<ref id="ref8"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Fink</surname> <given-names>A.</given-names></name> <name><surname>Kosecoff</surname> <given-names>J.</given-names></name> <name><surname>Chassin</surname> <given-names>M.</given-names></name> <name><surname>Brook</surname> <given-names>R. H.</given-names></name></person-group> (<year>1984</year>). <article-title>Consensus methods: characteristics and guidelines for use</article-title>. <source>Am. J. Public Health</source> <volume>74</volume>, <fpage>979</fpage>&#x2013;<lpage>983</lpage>. doi: <pub-id pub-id-type="doi">10.2105/AJPH.74.9.979</pub-id></citation></ref>
<ref id="ref9"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Fisher</surname> <given-names>R. J.</given-names></name> <name><surname>Riley-Bennett</surname> <given-names>F.</given-names></name> <name><surname>Russell</surname> <given-names>L.</given-names></name> <name><surname>Lee</surname> <given-names>C.</given-names></name> <name><surname>Sturt</surname> <given-names>R.</given-names></name> <name><surname>Walker</surname> <given-names>M.</given-names></name> <etal/></person-group>. (<year>2021</year>). <article-title>Nominal group technique to establish the core components of home-based rehabilitation for survivors of stroke with severe disability</article-title>. <source>BMJ Open</source> <volume>11</volume>:<fpage>e052593</fpage>. doi: <pub-id pub-id-type="doi">10.1136/bmjopen-2021-052593</pub-id>, PMID: <pub-id pub-id-type="pmid">34857570</pub-id></citation></ref>
<ref id="ref10"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Gattrell</surname> <given-names>W. T.</given-names></name> <name><surname>Hungin</surname> <given-names>A. P.</given-names></name> <name><surname>Price</surname> <given-names>A.</given-names></name> <name><surname>Winchester</surname> <given-names>C. C.</given-names></name> <name><surname>Tovey</surname> <given-names>D.</given-names></name> <name><surname>Hughes</surname> <given-names>E. L.</given-names></name> <etal/></person-group>. (<year>2022</year>). <article-title>ACCORD guideline for reporting consensus-based methods in biomedical research and clinical practice: a study protocol</article-title>. <source>Res. Integr. Peer Rev.</source> <volume>7</volume>:<fpage>3</fpage>. doi: <pub-id pub-id-type="doi">10.1186/s41073-022-00122-0</pub-id>, PMID: <pub-id pub-id-type="pmid">35672782</pub-id></citation></ref>
<ref id="ref11"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Herbert</surname> <given-names>R.</given-names></name> <name><surname>Jamtvedt</surname> <given-names>G.</given-names></name> <name><surname>Mead</surname> <given-names>J.</given-names></name> <name><surname>Hagen</surname> <given-names>K. B.</given-names></name></person-group> (<year>2005</year>). <article-title>Outcome measures measure outcomes, not effects of intervention</article-title>. <source>Aust. J. Physiother.</source> <volume>51</volume>, <fpage>3</fpage>&#x2013;<lpage>4</lpage>. doi: <pub-id pub-id-type="doi">10.1016/S0004-9514(05)70047-7</pub-id></citation></ref>
<ref id="ref12"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Hudon</surname> <given-names>A.</given-names></name> <name><surname>Lippel</surname> <given-names>K.</given-names></name> <name><surname>MacEachen</surname> <given-names>E.</given-names></name></person-group> (<year>2019</year>). <article-title>Mapping first-line health care providers&#x2019; roles, practices, and impacts on care for workers with compensable musculoskeletal disorders in four jurisdictions: a critical interpretive synthesis</article-title>. <source>Am. J. Ind. Med.</source> <volume>62</volume>, <fpage>545</fpage>&#x2013;<lpage>558</lpage>. doi: <pub-id pub-id-type="doi">10.1002/ajim.22972</pub-id>, PMID: <pub-id pub-id-type="pmid">31074020</pub-id></citation></ref>
<ref id="ref13"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kaplan</surname> <given-names>H. C.</given-names></name> <name><surname>Brady</surname> <given-names>P. W.</given-names></name> <name><surname>Dritz</surname> <given-names>M. C.</given-names></name> <name><surname>Hooper</surname> <given-names>D. K.</given-names></name> <name><surname>Linam</surname> <given-names>W. M.</given-names></name> <name><surname>Froehle</surname> <given-names>C. M.</given-names></name> <etal/></person-group>. (<year>2010</year>). <article-title>The influence of context on quality improvement success in health care: a systematic review of the literature</article-title>. <source>Milbank Q.</source> <volume>88</volume>, <fpage>500</fpage>&#x2013;<lpage>559</lpage>. doi: <pub-id pub-id-type="doi">10.1111/j.1468-0009.2010.00611.x</pub-id>, PMID: <pub-id pub-id-type="pmid">21166868</pub-id></citation></ref>
<ref id="ref14"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kelley</surname> <given-names>J. M.</given-names></name> <name><surname>Kraft-Todd</surname> <given-names>G.</given-names></name> <name><surname>Schapira</surname> <given-names>L.</given-names></name> <name><surname>Kossowsky</surname> <given-names>J.</given-names></name> <name><surname>Riess</surname> <given-names>H.</given-names></name></person-group> (<year>2014</year>). <article-title>The influence of the patient-clinician relationship on healthcare outcomes: a systematic review and meta-analysis of randomized controlled trials</article-title>. <source>PLoS One</source> <volume>9</volume>:<fpage>e94207</fpage>. doi: <pub-id pub-id-type="doi">10.1371/journal.pone.0094207</pub-id>, PMID: <pub-id pub-id-type="pmid">24718585</pub-id></citation></ref>
<ref id="ref15"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Lentz</surname> <given-names>T. A.</given-names></name> <name><surname>Goode</surname> <given-names>A. P.</given-names></name> <name><surname>Thigpen</surname> <given-names>C. A.</given-names></name> <name><surname>George</surname> <given-names>S. Z.</given-names></name></person-group> (<year>2020</year>). <article-title>Value-based care for musculoskeletal pain: are physical therapists ready to deliver?</article-title> <source>Phys. Ther.</source> <volume>100</volume>, <fpage>621</fpage>&#x2013;<lpage>632</lpage>. doi: <pub-id pub-id-type="doi">10.1093/ptj/pzz171</pub-id>, PMID: <pub-id pub-id-type="pmid">31764990</pub-id></citation></ref>
<ref id="ref16"><citation citation-type="book"><person-group person-group-type="author"><name><surname>Manera</surname> <given-names>K.</given-names></name> <name><surname>Hanson</surname> <given-names>C. S.</given-names></name> <name><surname>Gutman</surname> <given-names>T.</given-names></name> <name><surname>Tong</surname> <given-names>A.</given-names></name></person-group> (<year>2019</year>). &#x201C;<article-title>Consensus methods: nominal group technique</article-title>&#x201D; in <source>Handbook of research methods in health social sciences</source>. ed. <person-group person-group-type="editor"><name><surname>Liamputtong</surname> <given-names>P.</given-names></name></person-group> (<publisher-loc>Singapore</publisher-loc>: <publisher-name>Springer</publisher-name>)</citation></ref>
<ref id="ref17"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Mason</surname> <given-names>S.</given-names></name> <name><surname>Ling</surname> <given-names>J.</given-names></name> <name><surname>Mosoiu</surname> <given-names>D.</given-names></name> <name><surname>Arantzamendi</surname> <given-names>M.</given-names></name> <name><surname>Tserkezoglou</surname> <given-names>A. J.</given-names></name> <name><surname>Predoiu</surname> <given-names>O.</given-names></name> <etal/></person-group>. (<year>2021</year>). <article-title>Undertaking research using online nominal group technique: lessons from an international study (RESPACC)</article-title>. <source>J. Palliat. Med.</source> <volume>24</volume>, <fpage>1867</fpage>&#x2013;<lpage>1871</lpage>. doi: <pub-id pub-id-type="doi">10.1089/jpm.2021.0216</pub-id></citation></ref>
<ref id="ref18"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>McLaren</surname> <given-names>L.</given-names></name> <name><surname>Hawe</surname> <given-names>P.</given-names></name></person-group> (<year>2005</year>). <article-title>Ecological perspectives in health research</article-title>. <source>J. Epidemiol. Community Health</source> <volume>59</volume>, <fpage>6</fpage>&#x2013;<lpage>14</lpage>. doi: <pub-id pub-id-type="doi">10.1136/jech.2003.018044</pub-id>, PMID: <pub-id pub-id-type="pmid">15598720</pub-id></citation></ref>
<ref id="ref19"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>McMillan</surname> <given-names>S. S.</given-names></name> <name><surname>King</surname> <given-names>M.</given-names></name> <name><surname>Tully</surname> <given-names>M. P.</given-names></name></person-group> (<year>2016</year>). <article-title>How to use the nominal group and Delphi techniques</article-title>. <source>Int. J. Clin. Pharm.</source> <volume>38</volume>, <fpage>655</fpage>&#x2013;<lpage>662</lpage>. doi: <pub-id pub-id-type="doi">10.1007/s11096-016-0257-x</pub-id>, PMID: <pub-id pub-id-type="pmid">26846316</pub-id></citation></ref>
<ref id="ref20"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Michel</surname> <given-names>D. E.</given-names></name> <name><surname>Iqbal</surname> <given-names>A.</given-names></name> <name><surname>Faehrmann</surname> <given-names>L.</given-names></name> <name><surname>Tadi&#x0107;</surname> <given-names>I.</given-names></name> <name><surname>Paulino</surname> <given-names>E.</given-names></name> <name><surname>Chen</surname> <given-names>T. F.</given-names></name> <etal/></person-group>. (<year>2021</year>). <article-title>Using an online nominal group technique to determine key implementation factors for COVID-19 vaccination programmes in community pharmacies</article-title>. <source>Int. J. Clin. Pharm.</source> <volume>43</volume>, <fpage>1705</fpage>&#x2013;<lpage>1717</lpage>. doi: <pub-id pub-id-type="doi">10.1007/s11096-021-01335-x</pub-id>, PMID: <pub-id pub-id-type="pmid">34633625</pub-id></citation></ref>
<ref id="ref21"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Miciak</surname> <given-names>M.</given-names></name> <name><surname>Gross</surname> <given-names>D. P.</given-names></name> <name><surname>Joyce</surname> <given-names>A.</given-names></name></person-group> (<year>2012</year>). <article-title>A review of the psychotherapeutic &#x2018;common factors&#x2019; model and its application in physical therapy: the need to consider general effects in physical therapy practice</article-title>. <source>Scand. J. Caring Sci.</source> <volume>26</volume>, <fpage>394</fpage>&#x2013;<lpage>403</lpage>. doi: <pub-id pub-id-type="doi">10.1111/j.1471-6712.2011.00923.x</pub-id>, PMID: <pub-id pub-id-type="pmid">21913950</pub-id></citation></ref>
<ref id="ref22"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Nielsen</surname> <given-names>S. M.</given-names></name> <name><surname>Boers</surname> <given-names>M.</given-names></name> <name><surname>de Wit</surname> <given-names>M.</given-names></name> <name><surname>Shea</surname> <given-names>B.</given-names></name> <name><surname>van der Windt</surname> <given-names>D. A.</given-names></name> <name><surname>Reeves</surname> <given-names>B. C.</given-names></name> <etal/></person-group>. (<year>2021</year>). <article-title>OMERACT consensus-based operational definition of contextual factors in rheumatology clinical trials: a mixed methods study</article-title>. <source>Semin. Arthritis Rheum.</source> <volume>51</volume>, <fpage>601</fpage>&#x2013;<lpage>606</lpage>. doi: <pub-id pub-id-type="doi">10.1016/j.semarthrit.2021.03.013</pub-id></citation></ref>
<ref id="ref23"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Nielsen</surname> <given-names>S. M.</given-names></name> <name><surname>Tugwell</surname> <given-names>P.</given-names></name> <name><surname>de Wit</surname> <given-names>M. P. T.</given-names></name> <name><surname>Boers</surname> <given-names>M.</given-names></name> <name><surname>Beaton</surname> <given-names>D. E.</given-names></name> <name><surname>Woodworth</surname> <given-names>T. G.</given-names></name> <etal/></person-group>. (<year>2019</year>). <article-title>Contextual factors working group. Identifying provisional generic contextual factor domains for clinical trials in rheumatology: results from an OMERACT initiative</article-title>. <source>J. Rheumatol.</source> <volume>46</volume>, <fpage>1159</fpage>&#x2013;<lpage>1163</lpage>. doi: <pub-id pub-id-type="doi">10.3899/jrheum.181081</pub-id>, PMID: <pub-id pub-id-type="pmid">30647174</pub-id></citation></ref>
<ref id="ref24"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Ojha</surname> <given-names>H. A.</given-names></name> <name><surname>Wyrsta</surname> <given-names>N. J.</given-names></name> <name><surname>Davenport</surname> <given-names>T. E.</given-names></name> <name><surname>Egan</surname> <given-names>W. E.</given-names></name> <name><surname>Gellhorn</surname> <given-names>A. C.</given-names></name></person-group> (<year>2016</year>). <article-title>Timing of physical therapy initiation for nonsurgical management of musculoskeletal disorders and effects on patient outcomes: a systematic review</article-title>. <source>J. Orthop. Sports Phys. Ther.</source> <volume>46</volume>, <fpage>56</fpage>&#x2013;<lpage>70</lpage>. doi: <pub-id pub-id-type="doi">10.2519/jospt.2016.6138</pub-id>, PMID: <pub-id pub-id-type="pmid">26755406</pub-id></citation></ref>
<ref id="ref25"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Potter</surname> <given-names>M.</given-names></name> <name><surname>Gordon</surname> <given-names>S.</given-names></name> <name><surname>Hamer</surname> <given-names>P.</given-names></name></person-group> (<year>2004</year>). <article-title>The nominal group technique: a useful consensus methodology in physiotherapy research</article-title>. <source>N. Z. J. Physiother.</source> <volume>32</volume>, <fpage>126</fpage>&#x2013;<lpage>130</lpage>.</citation></ref>
<ref id="ref4"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Rethorn</surname> <given-names>Z. D.</given-names></name> <name><surname>Cook</surname> <given-names>C. E.</given-names></name> <name><surname>Park</surname> <given-names>C.</given-names></name> <name><surname>Somers</surname> <given-names>T.</given-names></name> <name><surname>Mummaneni</surname> <given-names>P. V.</given-names></name> <name><surname>Chan</surname> <given-names>A. K.</given-names></name> <etal/></person-group>. (<year>2022</year>). <article-title>Social risk factors predicting outcomes of cervical myelopathy surgery</article-title>. <source>J. Neurosurg. Spine</source>, <volume>37</volume>, <fpage>41</fpage>&#x2013;<lpage>8</lpage>. doi: <pub-id pub-id-type="doi">10.3171/2021.12.SPINE21874</pub-id></citation></ref>
<ref id="ref26"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Rodeghero</surname> <given-names>J. R.</given-names></name> <name><surname>Cook</surname> <given-names>C. E.</given-names></name> <name><surname>Cleland</surname> <given-names>J. A.</given-names></name> <name><surname>Mintken</surname> <given-names>P. E.</given-names></name></person-group> (<year>2015</year>). <article-title>Risk stratification of patients with low back pain seen in physical therapy practice</article-title>. <source>Man. Ther.</source> <volume>20</volume>, <fpage>855</fpage>&#x2013;<lpage>860</lpage>. doi: <pub-id pub-id-type="doi">10.1016/j.math.2015.04.007</pub-id>, PMID: <pub-id pub-id-type="pmid">25936467</pub-id></citation></ref>
<ref id="ref27"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Rollet</surname> <given-names>Q.</given-names></name> <name><surname>Tron</surname> <given-names>L.</given-names></name> <name><surname>De Mil</surname> <given-names>R.</given-names></name> <name><surname>Launoy</surname> <given-names>G.</given-names></name> <name><surname>Guillaume</surname> <given-names>&#x00C9;.</given-names></name></person-group> (<year>2021</year>). <article-title>Contextual factors associated with cancer screening uptake: a systematic review of observational studies</article-title>. <source>Prev. Med.</source> <volume>150</volume>:<fpage>106692</fpage>. doi: <pub-id pub-id-type="doi">10.1016/j.ypmed.2021.106692</pub-id>, PMID: <pub-id pub-id-type="pmid">34166675</pub-id></citation></ref>
<ref id="ref28"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Sevilla Guerra</surname> <given-names>S.</given-names></name> <name><surname>Jean</surname> <given-names>E.</given-names></name> <name><surname>Kilpatrick</surname> <given-names>K.</given-names></name> <name><surname>Zabalegui</surname> <given-names>A.</given-names></name> <name><surname>Mart&#x00ED;nez Gaitero</surname> <given-names>C.</given-names></name></person-group> (<year>2022</year>). <article-title>Contextual factors of advanced practice nursing development: a network analysis</article-title>. <source>Int. J. Nurs. Pract.</source>:<fpage>e13114</fpage>. doi: <pub-id pub-id-type="doi">10.1111/ijn.13114</pub-id></citation></ref>
<ref id="ref29"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Sharpe</surname> <given-names>J. A.</given-names></name> <name><surname>Miller</surname> <given-names>R.</given-names></name> <name><surname>Cook</surname> <given-names>C. E.</given-names></name> <etal/></person-group>. (<year>2023</year>). <article-title>Social risk factors are associated with disability prevalence &#x2013; results from 17 states in the 2017 behavioral risk factor surveillance system</article-title>. <source>Am. J. Health Promot.</source> <volume>37</volume>, <fpage>453</fpage>&#x2013;<lpage>463</lpage>. doi: <pub-id pub-id-type="doi">10.1177/08901171221132390</pub-id></citation></ref>
<ref id="ref30"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Sherriff</surname> <given-names>B.</given-names></name> <name><surname>Clark</surname> <given-names>C.</given-names></name> <name><surname>Killingback</surname> <given-names>C.</given-names></name> <name><surname>Newell</surname> <given-names>D.</given-names></name></person-group> (<year>2022</year>). <article-title>Impact of contextual factors on patient outcomes following conservative low back pain treatment: systematic review</article-title>. <source>Chiropr. Man. Therap.</source> <volume>30</volume>:<fpage>20</fpage>. doi: <pub-id pub-id-type="doi">10.1186/s12998-022-00430-8</pub-id></citation></ref>
<ref id="ref31"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Smith</surname> <given-names>D.</given-names></name> <name><surname>Cartwright</surname> <given-names>M.</given-names></name> <name><surname>Dyson</surname> <given-names>J.</given-names></name> <name><surname>Hartin</surname> <given-names>J.</given-names></name> <name><surname>Aitken</surname> <given-names>L. M.</given-names></name></person-group> (<year>2022</year>). <article-title>Selecting intervention content to target barriers and enablers of recognition and response to deteriorating patients: an online nominal group study</article-title>. <source>BMC Health Serv. Res.</source> <volume>22</volume>:<fpage>766</fpage>. doi: <pub-id pub-id-type="doi">10.1186/s12913-022-08128-6</pub-id>, PMID: <pub-id pub-id-type="pmid">35689227</pub-id></citation></ref>
<ref id="ref32"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Testa</surname> <given-names>M.</given-names></name> <name><surname>Rossettini</surname> <given-names>G.</given-names></name></person-group> (<year>2016</year>). <article-title>Enhance placebo, avoid nocebo: how contextual factors affect physiotherapy outcomes</article-title>. <source>Man. Ther.</source> <volume>24</volume>, <fpage>65</fpage>&#x2013;<lpage>74</lpage>. doi: <pub-id pub-id-type="doi">10.1016/j.math.2016.04.006</pub-id></citation></ref>
<ref id="ref33"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Tousignant-Laflamme</surname> <given-names>Y.</given-names></name> <name><surname>Martel</surname> <given-names>M. O.</given-names></name> <name><surname>Joshi</surname> <given-names>A. B.</given-names></name> <name><surname>Cook</surname> <given-names>C. E.</given-names></name></person-group> (<year>2017</year>). <article-title>Rehabilitation management of low back pain &#x2013; it&#x2019;s time to pull it all together!</article-title> <source>J. Pain Res.</source> <volume>10</volume>, <fpage>2373</fpage>&#x2013;<lpage>2385</lpage>. doi: <pub-id pub-id-type="doi">10.2147/JPR.S146485</pub-id>, PMID: <pub-id pub-id-type="pmid">29042813</pub-id></citation></ref>
<ref id="ref34"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>van Zuuren</surname> <given-names>E. J.</given-names></name> <name><surname>Logullo</surname> <given-names>P.</given-names></name> <name><surname>Price</surname> <given-names>A.</given-names></name> <name><surname>Fedorowicz</surname> <given-names>Z.</given-names></name> <name><surname>Hughes</surname> <given-names>E. L.</given-names></name> <name><surname>Gattrell</surname> <given-names>W. T.</given-names></name></person-group> (<year>2022</year>). <article-title>Existing guidance on reporting of consensus methodology: a systematic review to inform ACCORD guideline development</article-title>. <source>BMJ Open</source> <volume>12</volume>:<fpage>e065154</fpage>. doi: <pub-id pub-id-type="doi">10.1136/bmjopen-2022-065154</pub-id>, PMID: <pub-id pub-id-type="pmid">36201247</pub-id></citation></ref>
<ref id="ref35"><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Young</surname> <given-names>R.</given-names></name> <name><surname>Sage</surname> <given-names>K.</given-names></name> <name><surname>Broom</surname> <given-names>D.</given-names></name> <name><surname>Broomfield</surname> <given-names>K.</given-names></name> <name><surname>Church</surname> <given-names>G.</given-names></name> <name><surname>Smith</surname> <given-names>C.</given-names></name></person-group> (<year>2021</year>). <article-title>Using nominal group technique to advance power assisted exercise equipment for people with stroke</article-title>. <source>Res. Involv. Engagem.</source> <volume>7</volume>:<fpage>68</fpage>. doi: <pub-id pub-id-type="doi">10.1186/s40900-021-00311-z</pub-id>, PMID: <pub-id pub-id-type="pmid">34583773</pub-id></citation></ref>
</ref-list>
</back>
</article>
