with similar ratings provided by PD researchers (Lynam & Widiger, 2001) was even better, with coefficients that ranged from .90 (dependent) to .97 (antisocial). Samuel and Widiger concluded that "clinicians can conceptualize and apply the FFM to personality disorders in a consistent way" (p. 286).
These three studies have provided compelling documentation that clinicians are able to conceptualize personality disorders in terms of the FFM. However, they are limited in their coverage of clinical utility, being confined to just one of the six components emphasized by First et al. (2004), case conceptualization, and none of the studies actually asked the clinicians whether they found the FFM descriptions to be clinically useful. Sprock (2003) provides the only study to date that has explicitly addressed judgments concerning clinical utility, and much of her findings were not supportive of the FFM.
Sprock (2003) surveyed two national samples of practicing psychologists and randomly assigned each person to read two of six brief case vignettes that described prototypic and non-prototypic personality disorders. After reading each vignette, the first sample was instructed to provide both categorical and dimensional ratings using the current DSM-IV personality diagnostic constructs. The other sample was asked to provide ratings of alternative dimensional models of personality, including the five broad domains of the FFM. After providing these ratings, they were asked to rate each model (FFM and DSM) on three measures of clinical utility. The three measures she included were usefulness for professional communication, case conceptualization, and treatment planning. Sprock reported that the clinicians rated the DSM significantly higher than the FFM on all three measures of clinical utility. The same pattern was