“We start where we are”: a qualitative study of barriers and pragmatic solutions to the assessment and reporting of implementation strategy fidelity

BACKGROUND: Fidelity measurement of implementation strategies is underdeveloped and underreported, and the level of reporting is decreasing over time. Failing to properly measure the factors that affect the delivery of an implementation strategy may obscure the link between a strategy and its outcomes. Barriers to assessing and reporting implementation strategy fidelity among researchers are not well understood. The aims of this qualitative study were to identify barriers to fidelity measurement and pragmatic pathways towards improvement. METHODS: We conducted in-depth interviews among researchers conducting implementation trials. We utilized a theory-informed interview approach to elicit the barriers and possible solutions to implementation strategy fidelity assessment and reporting. Reflexive-thematic analysis guided coding and memo-writing to determine key themes regarding barriers and solutions. RESULTS: Twenty-two implementation researchers were interviewed. Participants agreed that implementation strategy fidelity was an essential element of implementation trials and that its assessment and reporting should improve. Key thematic barriers focused on (1) a current lack of validated fidelity tools with the need to assess fidelity in the short term, (2) the complex nature of some implementation strategies, (3) conceptual complications when assessing fidelity within mechanisms-focused implementation research, and (4) structural issues related to funding and publishing. Researchers also suggested pragmatic solutions to overcome each barrier. Respondents reported using specification and tracking data in the short term until validated tools become available. Participants suggested that researchers with strategy-specific content expertise lead the way in identifying core components and setting fidelity requirements for them. Addressing the third barrier, participants provided examples of what pragmatic prospective and retrospective fidelity assessments might look like along a mechanistic pathway. Finally, researchers described approaches to minimize costs of data collection, as well as more structural accountability like adopting and enforcing reporting guidelines or changing the structure of funding opportunities. DISCUSSION: We propose short- and long-term priorities for improving the assessment and reporting of implementation strategy fidelity and the quality of implementation research. CONCLUSIONS: A better understanding of the barriers to implementation strategy fidelity assessment may pave the way towards pragmatic solutions.