Normal and Abnormal Personality in Relation to Multiple Domains of Quality of Life

Abstract

The current study set out to investigate latent personality trait domains, from adaptive to maladaptive, by examining how these domains relate to quality of life. Specifically, we were interested in if these domains had nonlinear relationships with quality of life. Three samples were utilized in this study all of which were drawn from the U.S. Personality trait domains was measured via the IPIP-NEO (Goldberg et al., 2006) and PID-5 (Krueger et al., 2012), while quality of life was measured with the WHOQOL-BREF (Skevington, Lotfy, & O'Connell, 2004). Data were converted to ordinal measurement by averaging all items from each facet together. Scores were then converted to t-scores by using the mean and standard deviation for each facet in each respective sample. Orthogonal polynomial regression was used up to the cubic term to explore the nature of the relationship between each individual trait domain, as well as four combined domains found by Suzuki et al. (2015) that represent adaptive/maladaptive personality domain continua (i.e. Agreeableness vs Antagonism, Disinhibition vs Conscientiousness, Detachment vs Extraversion, Negative affectivity vs Emotional Stability). Local regression (LOESS) was then utilized to visualize any nonlinear relationships that were found by the orthogonal polynomial regressions. Results indicate that the relationship between the IPIP-Neuroticism, Negative affectivity vs Emotional Stability, IPIP-Extraversion, Detachment vs Extraversion, IPIP-Conscientiousness, and Disinhibition vs Conscientiousness and multiple areas of quality of life seem to be nonlinear. These results indicate that there may be ideal trait levels to maximize quality of life.