Audit and feedback had small but potentially important improvements in professional practice.

Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Effective Practice and Organisation of Care (EPOC) Group Specialised Register, Medline, Ovid; Embase, CINAHL, EBSCO, Science Citation Index and Social Sciences Citation Index, ISIWeb of Science Randomised trials of audit and feedback that reported objectively measured health professional practice or patient outcomes. Data were abstracted by two independent review authors using a data extraction form. The following factors were examined as possible explanations for the variation in the effectiveness of interventions across comparisons; format of feedback, source of feedback, frequency of feedback, instructions for improvement, direction of change required, baseline performance, profession of recipient and risk of bias within the trial itself. Risk of bias was assessed using EPOC criteria. The degree of confidence in the estimate of effect across studies was assessed using the GRADE approach. All outcomes were expressed as compliance with desired practice and both professional and patient outcomes were assessed, though separately. One hundred and forty studies were included. Using 70 of these 108 comparisons were made. After excluding studies at high risk of bias there were 82 comparisons from 49 studies with dichotomous outcomes, and the weighted median adjusted RD was 4.3% (interquartile range (IQR) 0.5% to 16%). For studies with continuous outcomes the weighted median adjusted percentage change relative to control was 1.3% (IQR = 1.3%to 28.9%). For patient outcomes the weighted median RD was 0.4% (IQR -1.3% to 1.6%) in studies reporting dichotomous outcomes, and the weighted median percentage change was 17% (IQR 1.5% to 17%) for studies with continuous outcomes. Multivariable meta-regression indicated that feedback may be more effective when baseline performance is low, the source is a supervisor or colleague, it is provided more than once, it is delivered in both verbal and written formats and when it includes both explicit targets and an action plan. Audit and feedback generally lead to small but potentially important improvements in professional practice.