How blind is double blind? And does it matter?
Journal/Book: British Journal of Clinical Pharmacology. 1976; 3: 331-332.
Abstract: 1.In an apparently double blind crossover study, two experienced measurement technicians -_ were able to identify many of the treatment periods. 2 They most often correctly identified aspirin, a drug with prominent effects and side effects. 3 It is argued that in many circumstances it is better to use a blind observer who is not concerned with the giving of treatment or the collection of side effects.