Maiman 1979.

Methods	DESIGN: Randomised factorial study of three types of intervention. METHOD OF RANDOMISATION: Control group were those who presented to emergency unit on the shifts that the "asthmatic" nurse wasn't on duty. Subjects were systematically assigned to the initial intervention on the basis of when the asthmatic nurse worked. Randomisation to sequential interventions not described. METHOD OF ALLOCATION CONCEALMENT: allocated to intervention groups or control on the basis of when the shift nurse worked thus not concealed. OUTCOME ASSESSOR BLINDING: unclear. WITHDRAWAL/DROPOUTS: not clearly described.
Participants	Eligibility Criteria: Eligible: 588 Randomised: 289 but control group excluded from analysis [44] Completed: Not specified Age: mean: 34.4years; Range 18‐64 years Sex: Male / Female ‐ 76.3% Female. Asthma Diagnosis: Doctor Recruitment: ER ‐ exit ‐ Johns Hopkins. Included: Major exclusions: 65yrs or older, chronic conditions with steroid therapy and patients admitted Baseline: based on number of ER visits for asthma in previous year. FEV1: Not stated PEF Not stated, Exacerbations Not stated.
Interventions	Intervention 1. Exit Interview with asthmatic nurse who identifies herself as asthmatic Exit Interview with asthmatic nurse who does not identify herself as asthmatic Exit interview with other ER nurse Intervention 2. Booklet Intervention 3. Another one to one interview Intervention 4. Follow‐up phone call (not really included as an intervention but randomised to receive follow‐up as authors thought it might impact upon results).
Outcomes	ER visits
Notes	Controls not reported. Questions for Authors: 1. Number of ER visits for the control group. 2. Number of ER visits for all interventions.
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	High risk	Subjects were systematically assigned to the initial intervention on the basis of when the asthmatic nurse worked
Allocation concealment?	High risk	Investigator aware as to order of allocation