A method for producing alcohol placebos

A method for producing placebo drinks that are hard to discriminate from alcoholic drinks is described. Subjects received a series of paired comparisons, each involving a distinctively flavoured alcoholic drink and one of six different placebo versions of it. Following each such comparison, rating scales were used to record the 'alcoholic strength' and 'sensory intensity' of a placebo drink relative to the alcoholic drink. The procedure was replicated using another distinctive alcoholic drink and another set of placebos. Based upon a multivariate analysis of subjects' ratings, the version of the placebo that was most difficult to discriminate from it's corresponding alcoholic drink was identified for both alcoholic drinks. The method is intended to be a general one for producing placebo versions of alcoholic drinks which do not differ on any dimensions which can be shown to be important in producing a response.