Using Item Response Theory to Develop a 60-Item Representation of the NEO PI-R Using the International Personality Item Pool: Development of the IPIP-NEO-60.

Given advantages of freely available and modifiable measures, an increase in the use of measures developed from the International Personality Item Pool (IPIP), including the 300-item representation of the Revised NEO Personality Inventory (NEO PI-R; Costa & McCrae, 1992a ) has occurred. The focus of this study was to use item response theory to develop a 60-item, IPIP-based measure of the Five-Factor Model (FFM) that provides equal representation of the FFM facets and to test the reliability and convergent and criterion validity of this measure compared to the NEO Five Factor Inventory (NEO-FFI). In an undergraduate sample (n = 359), scores from the NEO-FFI and IPIP-NEO-60 demonstrated good reliability and convergent validity with the NEO PI-R and IPIP-NEO-300. Additionally, across criterion variables in the undergraduate sample as well as a community-based sample (n = 757), the NEO-FFI and IPIP-NEO-60 demonstrated similar nomological networks across a wide range of external variables (rICC = .96). Finally, as expected, in an MTurk sample the IPIP-NEO-60 demonstrated advantages over the Big Five Inventory-2 (Soto & John, 2017 ; n = 342) with regard to the Agreeableness domain content. The results suggest strong reliability and validity of the IPIP-NEO-60 scores.

Gender Bias in the Measurement of Workaholism.

Past research suggests gender differences in workaholism might be due to differences in how men and women respond to the item content in workaholism measures. Using item response theory differential item functioning, we show women are less likely to report some workaholism items, leading to contamination. Specifically, women are less likely to report spending more time at work than other activities, and staying at work longer than others. We speculate that societal norms and practical restrictions on women's time results in lower endorsement rates for these items compared to men, and thus underestimates their workaholism. Results contradict past findings that men and women are similar in regard to workaholism and suggest women are in fact higher in workaholism than men. Limitations and future directions are discussed.

The Downsides of Extreme Conscientiousness for Psychological Well-being: The Role of Obsessive Compulsive Tendencies.

Although conscientiousness exhibits positive relations with psychological well-being, theoretical and empirical work suggests individuals can be too conscientious, resulting in obsessive-compulsiveness, and therein less positive individual outcomes. However, the potential for curvilinearity between conscientiousness and well-being has been underexplored. We measured 912 subjects on facets of conscientiousness, obsessive-compulsive personality, and well-being variables (life satisfaction, job satisfaction, self-esteem, positive affect, negative affect, work stress). Methods of scoring included traditional sum-scoring, traditional item response theory (IRT), and a relatively new IRT approach. Structural models were estimated to evaluate curvilinearity. Results confirmed the curvilinear relationship between conscientiousness and well-being, and demonstrated that differential facet-level relationships underlie weaker curvilinearity at the general trait level. Consistency was found in the strength of relation between conscientiousness facets with their obsessive-compulsive variants and their contribution to decreased well-being. The most common association was that higher standing on conscientiousness facets was positively related to negative affect. Findings support the idea that extreme standing on facets of conscientiousness more strongly linked to their obsessive-compulsive variants contributed to lower well-being, highlighting the importance of considering alternative functional representations of the relationship between personality and other constructs. Future work should seek to further clarify the link between conscientiousness and negative affect.

Testing whether the DSM-5 personality disorder trait model can be measured with a reduced set of items: An item response theory investigation of the Personality Inventory for DSM-5.

The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) includes an alternative model of personality disorders (PDs) in Section III, consisting in part of a pathological personality trait model. To date, the 220-item Personality Inventory for DSM-5 (PID-5; Krueger, Derringer, Markon, Watson, & Skodol, 2012) is the only extant self-report instrument explicitly developed to measure this pathological trait model. The present study used item response theory-based analyses in a large sample (n = 1,417) to investigate whether a reduced set of 100 items could be identified from the PID-5 that could measure the 25 traits and 5 domains. This reduced set of PID-5 items was then tested in a community sample of adults currently receiving psychological treatment (n = 109). Across a wide range of criterion variables including NEO PI-R domains and facets, DSM-5 Section II PD scores, and externalizing and internalizing outcomes, the correlational profiles of the original and reduced versions of the PID-5 were nearly identical (rICC = .995). These results provide strong support for the hypothesis that an abbreviated set of PID-5 items can be used to reliably, validly, and efficiently assess these personality disorder traits. The ability to assess the DSM-5 Section III traits using only 100 items has important implications in that it suggests these traits could still be measured in settings in which assessment-related resources (e.g., time, compensation) are limited.