The Schedule for Nonadaptive and Adaptive Personality: A Useful Tool for Diagnosis and Classification of Personality Disorder

Abstract

This chapter discusses new theoretical and research developments related to the Schedule for Adaptive and Nonadaptive Personality-2 (SNAP-2; Clark, Simms, Wu, & Casillas, in press) in the context of the forthcoming Diagnostic and Statistical Manual of Mental Disorders (DSM-5), particularly regarding personality disorder (PD). The theoretical underpinnings of dimensional taxonomies of personality traits and PD, and between personality and psychosocial functioning, are considered first. Next, recent SNAP-2 research is reviewed, most notably in the areas of dependency, impulsivity, and schizotypy. In aggregate, the findings suggest that existing SNAP-2 scales cover significant variance in these content domains, but that a SNAP-3 would benefit by increased coverage of each, specifically active/emotional dependency, carefree/-less behavior, and schizotypal disorganization. Information about additional SNAP versions for informant ratings and adolescent personality/PD, respectively, is provided. Finally, the utility of a program of research elucidating relations between personality and functioning is presented.

Development and Validation of the Schedule for Nonadaptive and Adaptive Personality Brief Self-Description Rating Form (SNAP-BSRF)

“…We hope that the SNAP-BSRF may represent a viable, more efficient alternative to the SNAP-SRF, pending more research on its validity and reliability in other samples. Given continuous research efforts in advocating for dimensional approaches to personality diagnosis based on maladaptive personality traits (Widiger, 2013;Widiger & Krueger, 2013) that highly overlap with the SNAP scales (Ro et al, 2012), the new, shorter version of the SNAP may be a very timely development.…”

“…Previous research using the SNAP was instrumental in developing the Personality Inventory for DSM-5 , which operationalizes the DSM-5 PD trait domains of Negative Affective, Detachment, Antagonism, Disinhibition, and Psychoticism (Krueger, Derringer, Markon, Watson, & Skodol, 2012; Markon, Quilty, Babgy, & Krueger, 2013; Wright et al, 2012). These higher-order trait domains are represented by 25 lower-order facets, such as emotional lability, restricted affectivity, and callousness; 21 of these facets are characterized by a significant level of overlap with the SNAP scales (Ro, Stringer, & Clark, 2012), suggesting that the SNAP measures are highly relevant to assessing personality pathology.…”

Comparability of self- and other-rated personality structure.

“…The SNAP is a comprehensive measure of adaptive-to-maladaptive-range personality traits whose scales were developed (a) bottom-up (i.e., without a priori consideration of a particular theoretical structure) and (b) based on the DSM and other descriptions of personality traits, additional traitlike manifestations of psychopathology (e.g., dysthymia), and adaptive-range personality traits. The SNAP family of measures has informed conceptualization of the broad structure of personality (e.g., they were included in the Markon et al, 2005, analyses; for descriptions of the measure’s various forms, see Ro, Stringer, & Clark, 2012; Simms & Clark, 2006) and generally has been shown to have a three-factor structure, although the measures include several interstitial scales (i.e., scales that are unidimensional but nevertheless cross-load on two factors; Clark & Watson, in press). Thus, use of these measures allows for a comprehensive examination of personality structure across raters, formats, and the normal–abnormal boundary.…”