The Beta-Agonist (Bags) study compared the safety and efficacy of regular plus "as needed" use of inhaled albuterol to the "as needed" use of inhaled albuterol in 255 patients with asthma of mild severity. A total of 230 patients completed the study. The study was randomized, double-blind, and placebo-controlled with parallel groups. Following a 6-week single-blind run-in period, patients were randomized in a double-blind manner and treated for 16 weeks. There was a 4-week withdrawal, or run-out, period. Changes in lung function and asthma symptoms were assessed to determine whether regular or "as needed" beta-agonist use was more beneficial in the treatment of mild asthma. Specific outcome measures included morning (AM) PEF, airway responsiveness, spirometric values, evening (PM) to AM PEF difference index, asthma symptoms, quality of life measures, use of rescue medications, and episodes of adverse asthma control. Recruitment began in December 1994. The study has completed and results have been published.