Yealy 2005.

Methods	STUDY DESIGN: cluster RCT, hospital level Risk of Bias: MEDIUM
Participants	PROVIDERS: all physicians in the ED PARTICIPANTS: 2075 patients admitted from ED (849 intervention, 1227 control), 32 clusters (EDs) CLINICAL PROBLEM: community‐acquired pneumonia SETTING: 32 EDs in the USA
Interventions	FORMAT: low‐intensity (control, 8 hospitals); moderate‐intensity (12 hospitals); and high‐intensity (12 hospitals) interventions Low‐intensity intervention: audit and feedback of baseline data; dissemination of guidelines Low‐intensity invervention functions: education, enablement Moderate‐intensity intervention: same as low intensity, but with additional on‐site educational meeting before patient enrolment Moderate‐intensity intervention additional function: education High‐intensity intervention: same as moderate with additional audit and feedback of data about management of individual patients within a week of enrolment plus 2 monthly feedback of group performance data; educational outreach through academic detailing with Plan Do Study Act cycles to discuss actions to be taken in response to group performance data High‐intensity intervention additional functions: education, enablement, persuasion DELIVERER: departmental physicians COMPARISON: usual care DESIRED CHANGE: increase effective: 4 process measures including time to first antibiotic dose POWER CALCULATION: Primary outcome was site of treatment rather than the antibiotic process measures. "We estimated that we would need 96 eligible patients per hospital (3072 in total) to achieve 80% power to detect a 12% difference across the intervention groups for the site‐of‐treatment decision among low‐risk patients." "For the site‐of‐treatment decision, this study achieved greater than 80% power to detect differences of 10% between high‐intensity and moderate‐intensity groups and differences of 12% between high‐intensity and low‐intensity groups according to separate 1‐tailed tests in which the level was 0.025."
Outcomes	PRESCRIBING: Choice: time to first antibiotic dose and choice compliant with guideline CLINICAL: Intended: mortality and medical complications
Notes	INSTRUCTIONS: action plan provided, no explicit target FINANCIAL SUPPORT: Funding: Agency for Healthcare Research and Quality (grant number R01 HS10049). National Institute of Allergy and Infectious Diseases (grant number K24 AI001769). Competing Interests: 1 author received consultancies, honoraria or grants from Genesoft Pharmaceuticals, Zynx Health Corporation, Healthcare Communications Inc., Stephen Lynn Klein, Kellogg Grants, and Pfizer Inc. ADDITIONAL DATA: email response from authors to request for additional data with care pathway, slide sets, order sheets, and protocol (Yealy 2004)
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"After stratifying emergency departments by state, teaching status, and annual volume, our statistician randomly assigned these departments to low‐intensity, moderate‐intensity, and high‐intensity guideline implementation strategies in the ratio of 2:3:3, respectively"
Allocation concealment (selection bias)	Low risk
Blinding (performance bias and detection bias) All outcomes	High risk	Not blinded
Incomplete outcome data (attrition bias) All outcomes	Low risk	Incomplete chart review on only 19 (0.6%) of 3219 patients
Selective reporting (reporting bias)	Low risk
Other bias	Low risk	"The target sample size included an adjustment of 30% to account for the clustering of patients within providers."
Baseline Outcomes similar?	Unclear risk	No data
Free of contamination?	Low risk	Cluster RCT
Baseline characteristics similar?	Low risk	Demographic characteristics differed between eligible patients who were and were not enrolled. Moreover, authors observed some imbalances in levels of illness severity across the intervention groups; however, their analyses of the site of treatment were performed separately for low‐risk and higher‐risk patients, and their multivariable analyses were not sensitive to the few imbalances that were observed at baseline.