The use was described of the DSM-III''s (Diagnostic and Statistical Manual of Mental Disorders III) diagnostic criteria and classification system as a research instrument in human psychopathology and discusses some of the advantages and drawbacks of DSM-III for a specific type of study. A rearrangement of the hierarchical order of the DSM-III diagnostic classes is suggested. This rearrangement provides for levels of certainty in analyzing interrater reliability and offers a simplified framework for summarizing group data. When this approach is combined with a structured interview and response format, it provides a flexible way of managing a large classification system for a smaller study without sacrificing standardization.