The present paper discusses methodological issues in psychopharmacological research. The intention is to provide readers of drug-evaluation research with a set of basic guidelines that will assist them to critically evaluate the investigations they encounter in the psychiatric literature. This paper describes the underlying rationale and basic principles associated with applying statistical analyses to drug-evaluation research data, and also addresses 11 additional methodological issues: specification of the research sample with respect to descriptive variables, diagnostic criteria, reliability of the diagnosis, the control group, random assignment of subjects to treatment conditions, blindness, subject attrition, treatment complications and side effects, the power of statistical tests, multivariate statistical analysis, and the reliability of the dependent variable. Evidence is presented to support the premise that there is a need to read drug-evaluation research critically.
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