Comparison of three different methods of monitoring unwanted effects during antihypertensive therapy

In a double-blind, randomized, crossover, multicenter study performed in 227 hypertensive outpatients, two antihypertensive drugs, oxprenolol and chlorthalidone, were investigated to determine unwanted effects. Three main methodologic procedures were applied: the conventional evaluation of unwanted effects by the physician and involving the whole patient population, the checklist, and the free questionnaire. The latter two were assigned by randomization to the patients themselves. The study showed that unwanted effects seem to be frequently overreported when a checklist is used, whereas the free questionnaire gives more information about the symptoms of the disease than about the tolerance of the drug. The conventional method, when physicians are well-informed and sensitized to the problem, seems to provide more reliable information about unwanted effects of a drug.