Burton 1991.

Methods	STUDY DESIGN: RCT Risk of Bias: HIGH
Participants	PROVIDERS: all physicians in hospital PARTICIPANTS: 147 receiving aminoglycosides CLINICAL PROBLEM: patients receiving IV aminoglycosides SETTING: 1 hospital in the USA
Interventions	FORMAT, Interventions: educational outreach by review and recommend change Intervention Functions: education, enablement, persuasion DELIVERER: pharmacist COMPARISON: usual care DESIRED CHANGE: reduce inappropriate POWER CALCULATION: no information about sample size
Outcomes	PRESCRIBING: Choice: aminoglycoside dosing and serum concentration CLINICAL: Intended: length of stay
Notes	FINANCIAL SUPPORT: no information ADDITIONAL DATA: no response from authors to request for additional data
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Random numbers table used to assign 9 of 17 house staff teams to the intervention group. Patients allocated to intervention or control groups based on house staff team to which they were admitted. The other 8 teams were assigned as control groups"
Allocation concealment (selection bias)	Unclear risk	Not stated but unlikely: 9 house staff teams were in the intervention group, 8 control, groups swapped over after 4 months.
Blinding (performance bias and detection bias) All outcomes	High risk	"Blinding as to patient status was not performed"
Incomplete outcome data (attrition bias) All outcomes	Low risk	No problems found.
Selective reporting (reporting bias)	Low risk	No problems found.
Other bias	High risk	Unit of analysis error for length of stay. This was a cluster RCT, but length of stay was analysed at participant level.
Baseline Outcomes similar?	Unclear risk	Not measured before interventions.
Free of contamination?	High risk	Not done, 9 house staff teams were in the intervention group, 8 control, groups swapped over after 4 months.
Baseline characteristics similar?	Low risk	See Table 2 in paper.