The selected publications were read, annotated, and entered into a Microsoft Excel spreadsheet. The data extraction sheet was piloted by A3 with two of the included studies, and then revised in consultation with A1. Next, the following information was extracted and classified by two members of the research team (A2, A3): access to technology (including methods of access), use of technology (i.e., frequency of use and purpose), impact on health outcomes, and key conclusions and implications for future research and/or practice. We also extracted basic information, including: authors, publication year, country of publication, study objectives, study design, methods, sample size, and sociodemographic characteristics.

The data extraction of A3 was validated by A2, and the data extraction of A2 was validated by an additional member of the research team. Publications reporting on data from the same study sample were considered a set, and counted as one study in the PRISMA diagram. In terms of summarizing the data, where applicable, simple weighted averages were calculated by A2 in consultation with a statistician based on study sample size for data pertaining to rates of access and use of ICTs, and for sociodemographic information (i.e., studies that did not report on a category of information were not included in the weighted average calculations). The qualitative data (e.g., reasons for using ICTs, methods of access, risks and benefits to ICT use) was coded by A2 and managed using Microsoft Excel and validated by an additional member of the research team. We did not conduct a critical appraisal of the included studies given that this is not typically an objective of conducting a scoping review (33, 35, 36) and the large research design heterogeneity of the studies reviewed.

Four studies reported on the rates that YEH access and use mobile phones; on average, 62.6% owned a mobile phone (32, 37–39). Based on two studies, an average of 68.8% specifically owned a smartphone (32, 38). The range of mobile phone ownership was wide (46.7-100%); for example, one study found that 78% of those in their quantitative analysis (n = 41) and 90% of those in their qualitative analysis (n = 52) owned a mobile phone (38), whereas another study found that their entire sample (n = 22) owned a mobile phone (37).

Eight studies reported on the rates that YEH access and use the internet; on average, 38.2% used the internet at least once daily, with a range of 28-86.5% (32, 40–46). Based on four studies, an average of 55.1% of YEH accessed the internet at least once a week, with a range of 45-93% (41, 43, 44, 46). Two of the studies reported that a significant majority of their sample used the internet regularly, but did not report on the actual frequency of access (32, 42).

Finally, 13 studies found that YEH access and use social media in some capacity (32, 37, 40, 43–52). Based on seven studies, an average of 77.1% used social media, with a range of 57-90.7% (32, 45–49, 52). Two of the studies reported on the frequency of YEH's social media use, with an average of 36.0% reporting daily social media use, and 26.6% reporting weekly use (47, 52).

Ten studies described how YEH accessed ICTs (32, 38–40, 42–46, 49). Cell phones were sometimes obtained as a gift, purchased with personal money, or with money obtained from panhandling, a job, or federal benefits (32, 38, 39). The internet was commonly accessed via a friend/family member's or publicly-available device; through public libraries and Wi-Fi; and through youth service community agencies, Internet cafes, schools, and workplaces (42–46, 49).

Eighteen studies addressed the reasons for YEH's use of ICTs (32, 37–53). Reasons for use most frequently cited were to navigate social networking sites (n = 13), to communicate with peers (n = 11) and family members (n = 9), to conduct job-related activities (n = 9), for communication generally (e.g., checking email; n = 8), and to seek health services (n = 5) and health-related information (n = 5). Table 2 provides additional details on the reasons for which YEH used ICTs.

Eleven studies identified factors that affected YEH's access to and use of ICTs (32, 37–42, 45, 46, 49, 54). The most cited factor was the actual living situation of the youth (n = 6), with youth experiencing homelessness or street-based living situations reporting less access to ICTs than youth who were able to find housing more consistently (32, 39, 41, 45, 46, 49). For example, one study found that participants residing in a house or an apartment were more likely to engage in regular use of social media (90.6%) than those living on the streets (55.6%) (32). Compared to when they were housed, YEH's internet behaviors became more goal-oriented, with less time spent on leisurely activities or entertainment (46).

Other factors affecting ICT access included the youth's financial situation and the availability of public devices. Unstable financial situations often led to phone deactivation due to missed payments, to sharing devices with a friend, to having the phone stolen, and difficulties in maintaining the device's functionality (e.g., charging the phone) (37, 38, 54). Some participants reported challenges accessing ICTs through public institutions, such as specific hours of operation, long wait times, downloading or printing difficulties, and website restrictions (42).

Despite the barriers they faced in accessing technology, one study found that youth reported comfort in using ICTs (70% self-assessed their computer abilities as better than average, and 85% reported being able to use a computer), due to previous family and school experiences. In addition, youth used ICTs for a diverse range of activities, suggesting a relatively high level of digital literacy (42).

Eleven studies established a link between the use of ICTs by YEH and to certain risks and benefits (38–40, 42, 44, 47, 49–53). The most common benefit was the ability to connect with positive social ties, such as home-based peers, family members and case workers, which was associated with a reduction in substance use, risky sexual health behaviors, and severity of mental health symptoms (40, 44, 47, 50, 52).

However, connecting with negative, street-based social ties was identified as the most common risk factor to using ICTs due to its association with an increased likelihood of engaging in risky sex behaviors (e.g., exchange sex, sex with someone met online) and substance abuse (40, 44, 47, 52). Further, discussing drinking, drugs, and sex on social networks with street-based ties was linked to an increase in risky health behaviors, in comparison to discussions of love or goals/future plans (47, 52).

The aims of our scoping review were to examine the ways that YEH access and use ICTs (i.e., frequency of use, purpose of use, barriers faced), and to discuss the implications of the findings for health care. We identified 16 studies (19 articles) demonstrating that there is a growing pool of evidence on access and use of ICTs among YEH, and that the use of ICTs plays an important role in their lives. At the same time, 16 studies of varying research design and sample sizes obtained through methods subject to sampling bias indicates an ongoing need for research on a highly marginalized population in urgent need for health care services (31).

In terms of our research questions, our key findings are: first, studies report high percentages of access to and use of ICTs by YEH (i.e., on average, across studies, 62.6% owned a mobile phone, with 68.8% owning a smartphone; 38.2% accessed the internet daily, with 55.1% reporting weekly access; and 77.1% used social media platforms). In comparison, surveys conducted with housed youth aged 13-17 in the USA and with youth aged 15-24 in Canada found that 92-96% of their samples went online daily, with nearly 75% of youth in the American sample reporting smartphone access (55, 56). The higher rates of ICT access in housed youth are unsurprising, considering that homelessness was linked to a decrease in internet use and access (32, 39, 41, 45, 46). However, it is important to note that the studies we reviewed are subject to sampling bias (i.e., recruitment from shelters, drop ins), and thus should be interpreted with caution. Moreover, accessibility to ICTs may differ depending on the country (e.g., prices of technology, public resources, governmental programs, etc.) and across regional areas (e.g., provinces, states, cities).

YEH diverge from youth in the general population in the methods and barriers to accessing ICTs. Many YEH rely on public computers in libraries and community agencies to access the Internet, which is accompanied by a diverse range of obstacles (e.g., wait lists, restrictions on site searches). Owning a cell phone also represents a financial burden for many YEH, who may need to panhandle or share the device with a friend to afford it, which can lead to its deactivation (38, 39, 43). These barriers can create a discontinuity in the sustainment of various social contacts for YEH and in the implementation of ICTs-based intervention.

Second, in the one study that discussed technology literacy, YEH reported confidence with their ICTs skills, due in part to exposure to technology at a young age (42). We also found that YEH used ICTs for an array of purposes, suggesting that they may be comfortable navigating and engaging with ICTs-enabled health interventions. However, given that few studies have addressed technology literacy in this population, and that research with other young populations shows that youth encounter several challenges in searching the internet for health-related information (57), this topic warrants further attention.

Third, our findings show that technology supported the maintenance of positive and healthy social contacts, which was associated with less depressive symptoms, a reduction in substance-using behaviors and more adequate sexual health behaviors (40, 44, 50, 51). This suggests that high accessibility to ICTs could also allow YEH to maintain good social relationships, influencing health outcomes. However, it should be noted that using ICTs to connect with street-based peers and to discuss drinking, drugs, and sex increased the likelihood of engaging in these risky health behaviors (44, 47, 51, 52). Thus, it is important to be cognizant of the nature of YEH's online connections, and encourage the use of ICTs to maintain positive social contacts.

The use of technology-enabled interventions with homeless populations is a new area of research and practice for healthcare professionals with several elements to consider, including: increasing access to technology, optimizing technology-based infrastructure, providing training for community outreach and health workers, and engaging service users in the development of diverse and contextually-sensitive interventions (58).

The high rates at which YEH are accessing and using ICTs for various goal-oriented behaviors indicates that technology plays a critical role in their lives. Prioritizing free and accessible technology in public settings (e.g., shelters, community centers, libraries, harm reduction centers) and free access to mobile devices, may be an important way to empower YEH, enable them to maintain connections with pro-social peers and family, and help build their awareness of public health guidelines, health services, and information.

Our findings support the notion that ICTs can improve communication with YEH for outreach purposes (31). Considering that YEH access and use a variety of ICTs, health care providers may consider ICT-based forms of communication to provide services and information. Concurrently, diversity in communicating with and disseminating information to YEH (i.e., using both online and offline methods) is an important factor to consider, given that not all YEH have regular access and use of technology, which may be further exacerbated during public health crises requiring physical distancing.

This scoping review has several limitations. We did not systematically assess the quality of studies given the heterogeneity of study methods, nor did we conduct a gray literature search. Similarly, due to time and human resources, only English language publications were included. It is therefore possible that some studies were omitted by the search strategy. In addition, as there was inconsistency in the ways in which papers reported their sociodemographic information and findings (e.g., eight papers reported on daily internet use, but only four of those papers additionally reported on weekly internet use), the weighted means reported in this review may not apply to the entirety of the study sample. Finally, as the present study is not a formal meta-analysis, we did not use more complex statistical pooling methods or analyze the heterogeneity in our data; as such, our results should be interpreted with these considerations in mind.

This scoping review highlights several research gaps, upon which we base the following recommendations: (1) international research is needed to understand YEH's access and use of ICTs, and to explore the impacts of varying infrastructures, government policies, and socioeconomic factors on YEH's experiences with technology; (2) more effort is needed to capture representative samples of the YEH population, characterizing the samples in terms of sociodemographic factors, and the role that these factors may play in their access and use of technology; (3) more consistency is needed in how access and use of technology is assessed and reported, as this will help to better synthesize the literature moving forward; (4) more research is needed on the digital health literacy skills of this population and their experiences of using technology to search for, and access health-related information and services; (5) quality appraisal will be an increasingly important consideration as more research emerges on access and use of ICTs among YEH; (6) more research is needed on how COVID-related public health guidelines affect access to publicly available ICTs (e.g., through libraries) and may further marginalize YEH from accessing critical health information and services; (7) future research should also focus on developing and evaluating technology-enabled health interventions for YEH. Indeed, we found that there is an emerging body of literature on the use of technology to deliver health related services to the homeless population, including youth. This is an important avenue to consider for a future review, to better examine the feasibility, acceptability, and efficacy of providing health services to YEH through this method of service delivery.