Harris 1984.

Methods	CCT unit of allocation: practices unit of analysis: episodes of care power calculation: not done concealment of allocation: not done follow up of professionals: not clear blinded assessment of primary outcome: done baseline measurement: done reliable primary outcome measure: done protection against contamination: done analysis appropriate: no
Participants	59 general practitioners in 22 practices in Great Britain treating patients of all ages for community acquired infection
Interventions	1. Educational meetings + audit and feedback + printed educational materials 2. No intervention control
Outcomes	Professional practice: Change in rate of prescribing penicillin Patient: None
Notes	No specific prescribing recommendations were made. Feedback data and workshops facilitated discussion of physicians' prescribing in general
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment?	Unclear risk	D ‐ Not used