Exploring perceived barriers and enablers to fidelity of training and delivery of an intervention to reduce imaging for low back pain: a qualitative interview study protocol

Background: Diagnostic imaging has limited utility in the assessment and management of non-specific low back pain (LBP), but remains commonly used in clinical practice. Interventions have been designed to reduce non-indicated imaging for LBP; however, evidence of effectiveness has been variable. It is unclear whether intervention fidelity was adequately assessed in these interventions, which may have an impact on the interpretation of trial results. Within implementation research, intervention fidelity refers to the degree to which an intervention was delivered as intended and to the strategies used to monitor and enhance this process. Intervention fidelity covers five domains: design, training, delivery, receipt, and enactment. Objectives: The objectives of this study are to explore perceived barriers and enablers to fidelity of training and delivery of a proposed theory-informed intervention aimed at reducing non-indicated imaging for LBP by general practitioners (GPs) and chiropractors in Newfoundland and Labrador (NL), Canada. Methods: Semi-structured interviews will be conducted with GPs and chiropractors in NL to explore their views on barriers and enablers towards enhancing and/or assessing fidelity of training and delivery. Interviews will be audio-recorded, transcribed verbatim, and analysed with the Theoretical Domains Framework. Relevant domains related to perceived barriers and enablers will be identified by: the frequency of beliefs; the presence of conflicting beliefs; and the perceived strength of the impact a belief may have on the target behaviours. Discussion: Results of this study will aid in the development of a fidelity protocol for an upcoming cluster randomised controlled trial of a theory-informed intervention aimed at reducing non-indicated imaging for LBP. Our results may help to ensure that the proposed intervention will be delivered with good fidelity and that fidelity can be appropriately assessed.