Eccles 2001.

Methods	Type of targeted behaviour: decrease in test ordering (lumbar and knee x‐rays) Study design: cluster RCT Country: UK
Participants	Setting: primary care 247 practices Condition: acute LBP or knee pain
Interventions	1. Professional intervention (distribution of educational materials + audit and feedback) 2. Professional intervention (distribution of educational materials + reminders) 3. Professional intervention (distribution of educational materials + audit and feedback + reminders) 4. Distribution of educational materials (guideline)
Outcomes	Professional practice: number of lumbar or knee radiographs requested per 1000 patients for 2 years Patient level: none
Notes	Justification for intervention type: not reported Intervention fidelity: in part. Measured attachment rate of educational reminder messages to x‐ray reports
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	Low risk	Computer‐generated random‐number tables
Allocation concealment?	Low risk	Performed centrally by study statistician
Blinding? All outcomes	Low risk	Outcome measure was objective and recorded by radiology departments
Incomplete outcome data addressed? All outcomes	Low risk
Free of selective reporting?	Low risk
Free of other bias?	High risk	Some baseline imbalance between study groups