The Collaborative Longitudinal Personality Disorders Study: development, aims, design, and sample characteristics.

This paper describes the aims, background, design, and methods used in a collaborative longitudinal study of Axis II personality disorders (PDs). This study examines the putative stability of selected PD diagnoses and criteria, what factors affect their course, and whether their stability and course distinguishes them from a representative Axis I disorder. This article also describes the acquisition and demographics of the sample on whom the study is being done. A prospective, repeated measures investigation of the stability of PDs is now underway at multiple clinical settings in four collaborating urban sites in Boston. New Haven, New York, and Providence. Diagnostic assignments are based on semistructured interview assessments (by clinically trained raters) and confirmed by at least one additional contrasting diagnostic method. The sample consists of 668 treatment seeking and reliably diagnosed adults recruited from a broad range of clinical sites. By design, patients in the sample met standards for one of five diagnostic subgroups: (a) schizotypal (N = 86); (b) borderline (N = 175); (c) avoidant (N = 157); (d) obsessive-compulsive (N = 153) personality disorders or a control group having (e) major depressive disorder without personality disorder (N = 97).