Showing papers by "Gordon H. Guyatt published in 1990"

The n-of-1 Randomized Controlled Trial: Clinical Usefulness: Our Three-Year Experience

Abstract: OBJECTIVE To review the feasibility and effectiveness of n-of-1 randomized controlled trials (n-of-1 trials) in clinical practice. DESIGN Individual trials were double-blind, randomized, multiple crossover trials. The impact of n-of-1 trials was determined by eliciting physicians' plans of management and confidence in those plans before and after each trial. SETTING Referral service doing n-of-1 trials at the requests of community and academic physicians. OBJECT of ANALYSIS All trials were planned, started, and completed by the n-of-1 service. MEASURES OF OUTCOME The proportion of planned n-of-1 trials that were completed and the proportion that provided a definite clinical or statistical answer. A definite clinical answer was achieved if an n-of-1 trial resulted in a high level of physician's confidence in the management plan. Specific criteria were developed for classifying an n-of-1 trial as providing a definite statistical answer. MAIN RESULTS Seventy-three n-of-1 trials were planned in various clinical situations. Of 70 n-of-1 trials begun, 57 were completed. The reasons for not completing n-of-1 trials were patients' or physicians' noncompliance or patients' concurrent illness. Of 57 n-of-1 trials completed, 50 provided a definite clinical or statistical answer. In 15 trials (39% of trials in which appropriate data were available), the results prompted physicians to change their "prior to the trial" plan of management (in 11 trials, the physicians stopped the drug therapy that they had planned to continue indefinitely). CONCLUSION We interpret the results as supporting the feasibility and usefulness of n-of-1 trials in clinical practice.

Aqueous beclomethasone diproprionate nasal spray: regular versus "as required" use in the treatment of seasonal allergic rhinitis.

Abstract: Objective: to determine the effect of alternative regimens of nasal steroid administration on symptoms and quality of life. Design: randomized, double-blind, parallel-group comparison. Subjects: sixty ragweed-sensitive adults recruited from participants of previous studies and through media advertising. Interventions: 200 μg of aqueous beclomethasone diproprionate nasal spray, twice daily, from 1 week before until 1 week after the ragweed-pollen season (regular) or 100 μg of the spray, taken as required, up to 400 μg daily; troublesome nasal symptoms were treated, in both groups, by increasing the daily dose to 800 μg until symptoms were controlled. If this treatment was insufficient, 120 mg of terfenadine, daily, was added. Results: One subject in the "as required"-treated group withdrew with uncontrolled nasal symptoms. In the remaining subjects, sneezing, stuffy nose, and rhinorrhea, measured by a daily diary, were significantly better controlled in the regular-treated group ( p p p =0.022). Eye symtoms and eye-drop use were similar in the two treated groups. Conclusion: In patients with seasonal allergic rhinitis, regular use of inhaled steroids results in fewer symptoms and better quality of life than when the spray is taken only as required.