Edna R. Fiedler

Perceptions of people with personality disorders based on thin slices of behavior

Strangers made reliable judgments about personality traits after viewing one 30-s excerpt from interviews with anonymous target persons. Ratings were generated for 229 military recruits participating in a study of personality disorders. Approximately 28% of the recruits met DSM-IV criteria for a definite or probable personality disorder (PD). Several untrained undergraduate students rated each video clip with regard to the Big Five personality traits, physical attractiveness, and likeability. The students accurately rated people who exhibited features of paranoid, schizotypal, dependent, and avoidant PDs as being lower in extraversion. The raters also considered these people less likeable. Students accurately rated people who exhibited features of histrionic PD as being higher in extraversion and found them to be more likeable. Laypersons can make accurate judgments regarding some personality characteristics associated with personality disorders, even on the basis of minimal information. These perceptions may influence ways in which people respond to others with PDs.

Traits Associated with Personality Disorders and Adjustment to Military Life: Predictive Validity of Self and Peer Reports

This study demonstrated that traits and features associated with several types of personality disorders are related to work performance and the ability to conform to requirements of military life. The Schedule for Nonadaptive and Adaptive Personality and a peer nomination procedure were used to assess traits associated with 10 types of personality disorders in a sample of 1,080 Air Force recruits (57% male) at the end of basic military training. Correlations between self-report and peer nomination scores for each set of traits ranged from 0.24 to 0.13, indicating only modest convergence. Follow-up data, collected 2 years later, indicated that several scores from the Schedule for Nonadaptive and Adaptive Personality and the peer nomination procedure were significantly related to early discharge from the military. Peers provide useful information that is not redundant with that provided by the individual. When possible, assessment of personality problems should be considered from information obtained from peers or other informants.

Predicting Outcome of Military Basic Training for Individuals Referred for Psychological Evaluation

We examined outcome data for 632 U.S. Air Force personnel who were referred for psychological evaluation during Basic Military Training (BMT) but who were subsequently returned to BMT to determine what proportion graduated. We analyzed motivational, biographical, and psychological testing variables, using logistic regression to develop a model predictive of training outcome. The results demonstrated that a relatively small number of variables could predict outcome with close to 70% accuracy. Level of optimism regarding training, history of physical abuse, and frequency of visits to the trainee health clinic were major contributors to the model. MMPI-2 (Hathaway & McKinley, 1989) Scales D and Sc also remained in the model but added little to its power. The findings are generally consistent with prior research on normal military populations, except that some factors previously linked to adjustment, such as sex and ethnicity, were found to be unrelated to training outcome in this population.

A comparison of three strategies for scale construction to predict a specific behavioral outcome.

Using 65 items from a mental health screening questionnaire, the History Opinion Inventory–Revised (HOI-R), the present study compared three strategies of scale construction—(1) internal (based on factor analysis), (2) external (based on empirical performance) and (3) intuitive (based on clinicians’ opinion)—to predict whether 203,595 U.S. Air Force trainees would be discharged early for mental health or behavior-related reasons within a 4-year follow-up period. The external strategy significantly outperformed the internal strategy, which in turn outperformed the intuitive strategy. For all strategies, predictive accuracy was consistently higher when items and scales were scored using empirically derived weights rather than unit weights. These findings suggest that the external strategy of scale construction provides the highest accuracy when sample sizes are large and the aim is to predict a specific behavioral event. However, the internal strategy also yields valid results and can be a reasonable choice when outcome data are unavailable.