AUTHOR=Kerins Claire , Kelly Colette , Reardon Caitlin M. , Houghton Catherine , Toomey Elaine , Hayes Catherine B. , Geaney Fiona , Perry Ivan J. , McSharry Jenny , McHugh Sheena TITLE=Factors Influencing Fidelity to a Calorie Posting Policy in Public Hospitals: A Mixed Methods Study JOURNAL=Frontiers in Public Health VOLUME=Volume 9 - 2021 YEAR=2021 URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2021.707668 DOI=10.3389/fpubh.2021.707668 ISSN=2296-2565 ABSTRACT=Background: Labelling menus with nutrition information has increasingly become an important obesity policy option. While much research to-date has focused on determining its effectiveness, few studies report the extent to which menu labelling is implemented as designed. The aim of this study was to explore factors influencing fidelity to a calorie posting policy in Irish acute public hospitals. Methods: A mixed methods sequential explanatory study design was employed, with a nested case study for the qualitative component. Quantitative data on implementation fidelity at hospitals were analysed first and informed case sampling in the follow-on qualitative phase. Data were collected using structured observations, unstructured non-participant observations and in-depth semi-structured interviews. The Consolidated Framework for Implementation Research guided qualitative data collection and analysis. Using framework analysis, factors influencing implementation were identified. A triangulation protocol was used to integrate fidelity findings from multiple sources. Data on influencing factors and fidelity were then combined using joint displays for within and cross-case analysis. Results: Four hospitals were selected as cases. Integrated findings on fidelity revealed an overall pattern of partial adherence to the calorie posting policy across hospitals. Across all hospitals, there was a consistent pattern of low adherence to calorie posting across all menu items on sale, low adherence to calorie information displayed per standard portion or per meal, low adherence to standardised recipes/portions, and inaccurate calorie information. Factors influencing implementation and within that, factors linked to fidelity, were multiple, and operated independently and in combination. Factors were related to the internal environment of the hospital (e.g. leadership support, access to knowledge and information, perceived importance of calorie posting implementation), external environment to the hospital (e.g. national policy, monitoring), features of the calorie posting policy (e.g. availability of supporting materials) and the process of implementation (e.g. engaging relevant stakeholders). Conclusion: Efforts to maximise fidelity require multi-level, multi-component strategies in order to reduce or mitigate barriers and to leverage facilitators. Future research should examine the relative importance of calorie posting determinants and the association between implementation strategies and shifts in fidelity to intervention core components.