The impact of removing financial incentives and/or audit and feedback on chlamydia testing in general practice: A cluster randomised controlled trial (ACCEPt-able)

Background Financial incentives and audit/feedback are widely used in primary care to influence clinician behaviour and increase quality of care. While observational data suggest a decline in quality when these interventions are stopped, their removal has not been evaluated in a randomised controlled trial (RCT), to our knowledge. This trial aimed to determine whether chlamydia testing in general practice is sustained when financial incentives and/or audit/feedback are removed. Methods and findings We undertook a 2 × 2 factorial cluster RCT in 60 general practices in 4 Australian states targeting 49,525 patients aged 16–29 years for annual chlamydia testing. Clinics were recruited between July 2014 and September 2015 and were followed for up to 2 years or until 31 December 2016. Clinics were eligible if they were in the intervention group of a previous cluster RCT where general practitioners (GPs) received financial incentives (AU$5–AU$8) for each chlamydia test and quarterly audit/feedback reports of their chlamydia testing rates. Clinics were randomised into 1 of 4 groups: incentives removed but audit/feedback retained (group A), audit/feedback removed but incentives retained (group B), both removed (group C), or both retained (group D). The primary outcome was the annual chlamydia testing rate among 16- to 29-year-old patients, where the numerator was the number who had at least 1 chlamydia test within 12 months and the denominator was the number who had at least 1 consultation during the same 12 months. We undertook a factorial analysis in which we investigated the effects of removal versus retention of incentives (groups A + C versus groups B + D) and the effects of removal versus retention of audit/feedback (group B + C versus groups A + D) separately. Of 60 clinics, 59 were randomised and 55 (91.7%) provided data (group A: 15 clinics, 11,196 patients; group B: 14, 11,944; group C: 13, 11,566; group D: 13, 14,819). Annual testing decreased from 20.2% to 11.7% (difference −8.8%; 95% CI −10.5% to −7.0%) in clinics with incentives removed and decreased from 20.6% to 14.3% (difference −7.1%; 95% CI −9.6% to −4.7%) where incentives were retained. The adjusted absolute difference in treatment effect was −0.9% (95% CI −3.5% to 1.7%; p = 0.2267). Annual testing decreased from 21.0% to 11.6% (difference −9.5%; 95% CI −11.7% to −7.4%) in clinics where audit/feedback was removed and decreased from 19.9% to 14.5% (difference −6.4%; 95% CI −8.6% to −4.2%) where audit/feedback was retained. The adjusted absolute difference in treatment effect was −2.6% (95% CI −5.4% to −0.1%; p = 0.0336). Study limitations included an unexpected reduction in testing across all groups impacting statistical power, loss of 4 clinics after randomisation, and inclusion of rural clinics only. Conclusions Audit/feedback is more effective than financial incentives of AU$5–AU$8 per chlamydia test at sustaining GP chlamydia testing practices over time in Australian general practice. Trial registration Australian New Zealand Clinical Trials Registry ACTRN12614000595617