Very little is known about the daily stability and fluctuation of personality pathology. To address this gap in knowledge, we investigated the naturalistic manifestation of personality pathology over the course of 100 days. A group of individuals (N=101) diagnosed with any personality disorder (PD) completed a daily diary study over 100 consecutive days (Mdn = 94 days, Range = 33-101 days). Participants completed daily ratings of 30 manifestations of personality pathology. Patterns of stability and variability over the course of the study were then examined. Results indicated that individual PD manifestations and domains of PD manifestations were variable across days and differed widely in their frequency. Additionally, individual averages and level of variability in PD domains were highly stable across months, individual averages of PD domains were predicted by baseline dispositional ratings of PD traits with a high degree of specificity, and daily variability PD domains was associated with elevated levels of PD traits. This pattern of findings suggests that dynamic processes of symptom exacerbation and diminution that are stable in mean level and variability in expression over time characterizes personality pathology. Further, dispositional ratings are significant predictors of average daily expression of PD features.
