Treatment of gastric ulcer. The randomized clinical trials from 1964 to 1974 and their impact.

Twenty-nine randomized clinical trials (RCTs) from the decade 1964-74 evaluating treatments of gastric ulcer have been analyzed. None of them ful-filled all criteria for an ideal RCT. The most frequent shortcomings were: short treatment or follow-up periods, incomplete description of the patients included, small patient samples, suboptimal experimental design, lack of double-blind testing, high number of drop-outs, less precise or less relevant types of evaluation of the treatment effect, uncontrolled ancillary treatment, or lack of statistical evaluation of the results. The most frequently tested drug was carbenoxolone, which has been shown to be clearly effective. Judged by the effect on the recommendations in standard medical textbooks the impact of the best RCTs have been small. This situation emphasizes the need for more well-planned and performed RCTs on treatments of gastric ulcer.