Feasibility of testing the effectiveness of a theory-informed intervention to reduce imaging for low back pain: a pilot cluster randomised controlled trial

Background: General medical practitioner (GP) recruitment and subsequent data collection in clinical practice are challenging and may limit successful completion of a large-scale trial. The aim of this study was to assess the feasibility of undertaking a cluster randomised controlled trial to test an intervention to reduce non-indicated imaging for low back pain in general medical practice.

Methods: A pilot cluster randomised controlled trial was performed, with recruitment of GPs and randomisation of GP clinics. All GPs attended a training session and were asked to record low back pain codes in electronic medical records for any low back pain presentations. Intervention group GPs were trained in the use of a patient education booklet to be used during low back pain patient visits. Control group GPs provided usual care. Outcomes for the proposed trial were collected to determine feasibility. GP recruitment was assessed as the proportion of GPs approached who consented to participate. Low back pain imaging outcomes were collected from electronic medical records (counts of patients presenting with low back pain) and from Australian healthcare administrative (Medicare) data (counts of imaging use). GP compliance with study procedures was assessed and qualitative data reported.

Results: Thirty-four GP clinics were approached, with four participating (12%). At these clinics, 13/19 (68%) GPs consented to participate, and 10/19 (53%) started the study. Outcome data were collected from medical records for all GPs. Three GPs (30%) withdrew consent to access Medicare data, limiting reporting of imaging outcome measures. Three GPs (30%) self-reported low compliance entering low back pain codes.

Conclusions: This pilot cluster randomised controlled trial demonstrated the feasibility of many aspects of a full-scale effectiveness study, while also identifying a number of challenges that need to be resolved. Recommendations related to GP recruitment, study compliance, data collection, and outcome measures were made to increase the success of a future trial.

Trial registration: Australia and New Zealand Clinical Trials Register (ANZCTR), Trial ID: ACTRN12619000991112; Registered 11 July 2019, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=376973.