Clinical Tests on Comparative Effectiveness of Analgesic Drugs

Abstract

A headache remedy, designated here as drug A is composed of ingredients a, b and c. Ingredient b was running short and the manufacturers wished to know whether or not the efficacy of this drug would be lowered through the omission of this ingredient. In order to answer this question, 2001 subjects suffering from frequent headaches were to be treated for two weeks on each occurrence of headaches with drug A, two weeks with drug B, which was composed of ingredients a and c, two weeks with drug C containing ingredients a and b and two weeks with drug D, a placebo consisting of ordinary lactate which is pharmacologically inactive. The four drugs were made to appear indentical in color, shape, size and taste. Neither the subjects nor the physicians administering the drugs were aware of the differences in the composition of the four drugs. Because of possible progressive sensitization or desensitization to the drugs, they were administered in different sequences as follows: