The criteria for schizotypal personality disorder, borderline personality disorder, avoidant personality disorder, and obsessive-compulsive personality disorder, despite limitations in available empirical evidence for their development, have undergone only minor revisions since their introduction in DSM-III. Despite the phenomenological heterogeneity of the DSM-IV personality disorder criteria sets—with criteria representing a variety of traits and symptomatic behaviors and reflecting sometimes normal and sometimes pathological dimensions of personality in clinical samples—these sets demonstrate high internal consistency by disorder both cross-sectionally and over time. The criteria also retain their rank order of prevalence over time within the personality disorder category, despite personality disorder syndromal and criterion improvement (remission).
A key strength of the study was the inclusion of a large number of subjects with clinically significant personality disorders who were assessed with operational criteria by raters trained to reliable standards (24
) and followed up by raters blind to prior diagnostic data. The shortcomings were that not all DSM-IV personality disorders were represented and that the results may not generalize to non-treatment-seeking personality disorder populations. With these strengths and limitations in mind, we present some implications that follow from the data.
The polythetic nature of the DSM-IV criteria for these disorders has often been criticized for its lack of a cohesive, prototypic hierarchy of characteristics and the fact that the system gives equal weight to criteria that may be less central to the personality disorder category they define. Indeed, we found differences among the criteria within each personality disorder—differences in prevalence and stability (or resistance to change) that reflect differences in the nature of the criteria that make up personality disorders. The criteria that are more frequent and enduring over time may reflect elements of personality or personality disorder that are closer to temperament and trait (constitutional proclivities to perceiving and acting/reacting). In contrast, those that are less pervasive and more changeable may be closer to symptomatic behaviors that are stress responsive and habitual (i.e., learned). The former relate more to nature, i.e., genetics and biology; the latter relate more to nurture and learning. The former may be prime targets for biological treatments; the latter, better targets for psychosocial interventions.
) has called for classifying personality disorders on the basis of dimensions that cut across existing categories within axis II and between axis II and axis I. Furthermore, Hyman suggested that the selection of particular dimensions should be based on “empirical factors such as heritability.” Our effort here was an attempt to identify potential core dimensions based on longitudinal prevalence and resistance to change as the parameters of external validity.
Based on these parameters, the criteria to emerge in borderline personality disorder were affective instability, anger, and impulsivity. These criteria reflect what others regard as core trait distortions or endophenotypes of borderline personality disorder, such as affective dysregulation/instability (26
) or impulsive aggression (26
). They reflect two dimensions that emerge recurrently in factor analyses of borderline personality disorder—dysregulated affect and dysregulated behavior (34
). They also reflect the time-varying course of the Collaborative Longitudinal Personality Disorders Study borderline personality disorder subjects, with affective dysregulation/instability associated with axis I major depressive disorder and post-traumatic stress disorder (36
). It may be that these trait criteria are closer to the core of borderline personality disorder’s biogenetic structures. Furthermore, the less pervasive and more changeable criteria such as self-injury or frantic efforts to avoid abandonment may be seen as secondary or reactive, insofar as such behaviors represent attempts to adapt to, defend against, or cope with pathological affective dysregulation and impulsive aggression (37
The trait-like criteria that emerged for avoidant personality disorder were regarding oneself as socially inept, feeling inadequate compared to others, and wanting evidence of being liked first before making social contacts. The common theme appears compatible with the internalizing dimension of anxious-misery identified by Kendler et al. (38
), a dimension resulting largely from the effects of genetic risk factors. The criteria perhaps reflect the early temperaments of shyness and behavioral inhibition, temperaments that intermittently find symptomatic behavioral expression in a variety of avoidant behaviors (39
The criteria that emerge as most common and trait-like for schizotypal personality disorder were paranoid ideation, ideas of reference, odd beliefs, and unusual experiences. These criteria probably represent milder variants of the cognitive distortion of reality that is central to the schizophrenia spectrum (40
). In schizotypal personality disorder this distortion exists in attenuated form and only intermittently becomes expressed behaviorally as oddness or coldness.
Less is known or hypothesized concerning underlying trait dimensions for obsessive-compulsive personality disorder. In fact, our longitudinal criterion data may provide the first clues of the existence and nature of such dimensions. The most prevalent/least changeable obsessive-compulsive personality disorder criteria were rigidity, perfectionism, and problems delegating; these criteria highlight elements of withholding, resistance to change, and the need to control. Do they, perhaps, suggest traits relating to the neurobiology of aggressive control that are intermittently expressed behaviorally as miserliness and/or strict morality?
Our findings carry implications for criterion selection for borderline personality disorder, schizotypal personality disorder, avoidant personality disorder, and obsessive-compulsive personality disorder in DSM-V. Insofar as the concept of stability and resistance to change remains central to the generic definition of axis II, the criteria emerging as most prevalent and least changeable over time are prime candidates for retention. Criteria that are less common and more changeable may require more scrutiny, or they may need to offer other advantages in order to be retained. For example, self-injury is one of the least prevalent and most remitting criteria of borderline personality disorder, yet as a symptomatic behavior it has high visibility and substantial diagnostic efficiency (positive predictive power) cross-sectionally (10
), over time (unpublished 2004 study by C. M. Grilo et al.), and across ethnically diverse samples (17
). Similarly, the criteria with the highest cross-sectional diagnostic positive predictive power are the symptomatic behaviors such as (observed) odd thinking for schizotypal personality disorder, avoids interpersonal situations for avoidant personality disorder, and concern with rules, details, and lists for obsessive-compulsive personality disorder (14
). Clearly, the criteria for these disorders vary in their utility as they do in their source.
Our findings may also shed light on the longitudinal instability of these personality disorders as diagnostic entities (21
), that is, the symptomatic behavioral criteria “remit” more quickly and more frequently than trait criteria and are largely responsible for dips below the DSM diagnostic threshold for personality disorder. Such criteria may be good markers of disorder (e.g., the high diagnostic efficiency of self-injury for borderline personality disorder) but not good criteria for the assessment of stability of personality disorder pathology.
In conclusion, the DSM-IV criteria for schizotypal personality disorder, borderline personality disorder, avoidant personality disorder, and obsessive-compulsive personality disorder vary in their longitudinal prevalence and stability within disorder. This variation suggests that these DSM-IV personality disorders are hybrids of more stable traits and less stable symptomatic behaviors. The variation also suggests that both sets of criteria are key to defining personality disorders—one set highlighting personality, the other set highlighting disorder.