Dale 1995.

Study characteristics
Methods	Study design: parallel RCT Country: USA Recruitment: community volunteers and smoking clinic attenders
Participants	71 smokers stratified according to light, moderate and heavy smoking rates, and motivated to quit 44% men, average age 48, average cigarettes per day: 26
Interventions	1) 11 mg/24‐hour nicotine patch 2) 22 mg/24‐hour nicotine patch 3) 44 mg/24‐hour nicotine patch 4) Placebo patch for 1 week followed by 11 or 22 mg patch for 7 weeks Duration of patch use: 8 weeks
Outcomes	PPA at 12 months Validation: blood cotinine Adverse events: measured daily for 6 days post‐baseline (treatment continued for 6 weeks)
Notes	This study was supported by Lederle Laboratories, Pearl River, NY. RH, IC and KO have worked on clinical research studies funded in part by Lederle Laboratories, Elan Pharmaceutical Research Corporation, Burroughs‐Wellcome and Kabi. Conflicts of interest: RH has received honoraria for educational activities from CibaGeigy Corporation, Marion Merrell Dow, Inc, and McNeil Pharmaceuticals. KO has received honoraria for educational activities from Elan Pharmaceutical Research Corporation.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "subjects ... were randomly assigned"
Allocation concealment (selection bias)	Unclear risk	Not stated
Blinding (performance bias and detection bias) All outcomes	Low risk	Quote: "To blind the subjects, staff, and investigators, each subject simultaneously wore three patches during the 6‐day inpatient phase"
Incomplete outcome data (attrition bias) All outcomes	Low risk	Apart from one light smoker dropping out from 44 mg group for nicotine toxicity in week 1, apparently no dropouts.