Briel 2006.

Methods	Study design: cluster‐randomised controlled trial Unit of randomisation: general practitioner (GP) Trial duration: January to May 2004 Recruitment: 345 eligible GPs (criteria undefined) from 2 Swiss cantons (Basel‐Stadt and Aargau), where self dispensation of drugs is not allowed. 30 GPs (providing written consent by 1 December 2003) were randomised to limited or full intervention groups (15 GPs each); the remaining 15 GPs (providing written consent by 1 January 2004) formed the non‐randomised control group Methods of data collection: baseline data for eligible GPs obtained from the registry of the Swiss Medical Association; GPs recorded patient baseline data; medical students conducted standardised patient follow‐up interviews at 7 and 14 days by telephone; pharmacists faxed all prescriptions with study labels to the study centre Length of follow‐up: 14 days
Participants	GPs recruited all consecutive and eligible adult patients: ≥ 18 years with symptoms of acute infections of the respiratory system (first experienced within the previous 28 days; including common cold, rhinosinusitis, pharyngitis, exudative tonsillitis, laryngitis, otitis media, bronchitis, exacerbated COPD or influenza) Exclusion: patients with pneumonia, not fluent in German, with intravenous drug use or psychiatric disorders, and not available for phone interviews or unable to give written informed consent
Interventions	Brief intervention name: patient‐centred communication training Recipients: GPs Providers: unclear Health professional components: evidence‐based guidelines (developed by 3 trial authors based on existing US guidelines, adapted to local conditions and reviewed by local experts) presented as a booklet and in a 2‐hour interactive seminar, plus a 6‐hour patient‐centred communication seminar in small groups (number not defined) and 2 hours of personal feedback by phone prior to the start of the trial. Training aimed to teach GPs how to understand and modify patients' concepts and beliefs about the use of antibiotics for ARIs. Physicians were taught to practice elements of active listening, to respond to emotional clues and tailor information given to patients. GPs identified patients' attitudes and readiness for behaviour change using a theoretical model (Prochaska and DiClemente 1992) Patient components: nil Materials: evidence‐based guidelines for the treatment of ARIs distributed as a booklet (http://www.bice.ch/publications/reports) Mode of delivery: booklet and face‐to‐face small‐group interactive patient‐centred communication seminar Duration and intensity: GPs attended 1 x 2‐hour interactive evidence‐based guidelines seminar and 1 x 6‐hour small group interactive patient‐centred communication seminar Comparator 1 (Limited intervention): evidence‐based guidelines presented as a booklet and in a 2‐hour interactive seminar alone Comparator 2 (Non‐randomised control): usual care (data not extracted)
Outcomes	Primary: antibiotic prescriptions dispensed by pharmacists < 2 weeks following initial consultation (prescriptions with study labels faxed by pharmacists to the study centre) Secondary: rates of different diagnoses of respiratory infections (GP records) Adherence to guidelines for antibiotic prescription (GP records) Days with restrictions from respiratory infection (patient follow‐up interview at 7 and 14 days) Days off work (patient follow‐up interview at 7 and 14 days) Re‐consultation rates (patient follow‐up interview at 7 and 14 days) Patient satisfaction (Patient Satisfaction Questionnaire; patient follow‐up interview at 7 and 14 days) Patient enablement (Patient Enablement Instrument; patient follow‐up interview at 7 and 14 days) Other: serious adverse events (independent monitoring board review of serious adverse events that occurred < 28 days of study enrolment)
Notes	Funding: yes Conflict of interest: none disclosed Published trial protocol: no Trial registration: not stated Ethics approval: yes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated list created by an independent institution
Allocation concealment (selection bias)	Low risk	Allocation to either intervention was concealed. However, method not stated. However, GPs recruited prior to randomisation
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Blinding of general practitioners and trial staff reported. As this trial had 3 arms (2 intervention arms where the intervention in each involved a seminar and distribution of evidence guidelines; 1 usual care arm), it is possible that the GPs in the intervention arms would not have known which intervention group they were in
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Medical students, blinded to the goal of the trial, were trained to conduct standardised follow‐up interviews at 7 and 14 days by phone Prescriptions with study labels faxed by pharmacists to the study centre were checked and entered into the database by a person blinded to the intervention group Trial authors assessed adherence of all prescriptions to guidelines independently and blinded to the intervention group
Incomplete outcome data (attrition bias) All outcomes	Low risk	GPs randomised into limited intervention (GPs = 15; patients = 293) and full intervention groups (GPs = 15; patients = 259); 15 GPs (285 patients) participated as non‐randomised controls (data not extracted). All GPs completed the trial. There were 290, 253 and a convenience sample of 93 patients (stratified by physician), respectively, interviewed at 7 days; and 287, 245 and 92 patients interviewed at 14 days. Reasons for loss to follow‐up reported
Selective reporting (reporting bias)	Low risk	All indicated results reported. Trial registration or published trial protocol not stated
Other bias	Unclear risk	Sample size (power) calculation: yes ITT or per protocol analysis: ITT Intraclass correlation (co‐efficient) reported: 4.0% and a design effect of 1.6% Low study baseline prescribing rates – full intervention (13.5%), limited intervention (15.7%) and non‐randomised control (21.4%) Highly motivated GPs: recruitment coincided with introduction of a new nation‐wide computer‐based reimbursement system and due to increased workload participating GPs considered to be highly motivated