System impact and methodological issues in the development of an empirical typology of psychiatric hospital residents.

The identification and categorization of similar objects or individuals into groups is a universal theme that permeates science and provides a conceptual framework to facilitate comprehension. For mental health administrators, a sound methodology to group individuals in a meaningful way would prove useful in the areas of general system understanding, as well as staffing, program planning and evaluation, and service system research, to name a few. Cluster analysis is a set of techniques that approach this grouping process empirically. Within the context of a large psychiatric hospital system, both the methodological processes involved in the application of cluster analysis and the resulting utility of such an analysis are discussed. Issues fundamental to the understanding of such a system are addressed. Special emphasis is placed on methodological issues regarding the application of cluster analytic techniques, which have left such techniques open for criticism. The value of such analyses, when used appropriately, is illustrated by the development of a stable, five-group typology of psychiatric hospital residents whose group characteristics are particularly germane to service system understanding. The implications of such a model for administration, planning, and research in a psychiatric hospital system are also addressed.