Investigating the fidelity of a community-based physical activity intervention

Abstract

Background: Despite advances in the field, evaluation of fidelity of physical activity interventions is still rarely undertaken. The aims of this study is to a) assess observed adherence to planned behaviour change techniques (BCTs) as specified in the intervention protocol by practitioners delivering the Live Active physical activity intervention, b) compare observed and planned adherence, c) compare observed and self-reported adherence and d) assess variation of delivered BCTs across practitioners. Methods Video recordings of at least 12 baseline consultations between practitioner and patient will be produced, content analysed and coded using a fidelity checklist developed a priori from the intervention protocol. Two raters will double code all video recordings. Observed adherence will be compared to planned and self-reported practitioner adherence. Self-reported adherence will be assessed by asking practitioners to fill in the fidelity checklist after the consultation. Expected results: Differences between planned and observed adherence to BCTs and between observed and self-reported adherence are expected, in line with previous studies. Given that only the baseline consultation is being evaluated, BCTs to facilitate initial behaviour change (e.g., goal setting) are expected to be present more frequently than other techniques. Current stage of work: Fidelity checklist is currently being developed by the main author and practitioners are being recruited to take part in the study. Discussion: Evaluating fidelity of interventions as delivered in practice is crucial for understanding factors contributing to, or hindering, intervention efficacy. Such analyses can help refine interventions so that they better fit the delivery context.