METHODS
Subjects, Screening, and Randomization
Subjects were recruited at four study sites by advertisements in the media. The first subject was enrolled in August 1995, and follow-up was completed in March 1997. Of a total of 1182 persons who were screened, 893 met the screening criteria and were enrolled: 218 in Arizona, 227 in California, 220 in Nebraska, and 228 in Wisconsin. The subjects were randomly assigned to one of four treatments with use of an unequal-cell design: 160 subjects were assigned to receive placebo, 244 to receive the nicotine patch, 244 to receive bupropion, and 245 to receive bupropion and the nicotine patch. Randomization was not balanced within sites.