Integrating structure and dynamics in personality assessment: First steps toward the development and validation of a personality dynamics diary.

Both theories and cutting-edge research highlight the dynamic nature of personality and personality pathology, thereby posing significant challenges for an exclusively between-person, trait-based approach to personality assessment. In a series of 3 studies, we explored the viability of integrating within-person, dynamic aspects into clinical personality assessment by means of daily dairy methods. In the 1st study, 314 students filled out a 73-item questionnaire capturing daily behaviors and situation experiences across 7-10 consecutive days. We used multilevel exploratory factor analyses to construct a shortened version, the Personality Dynamics Diary (PDD). In the 2nd study, the PDD was applied in a sample of 77 psychotherapy inpatients across 40 days, on average. In the 3rd study, 35 psychotherapy outpatients as well as their therapists judged the clinical utility of a smartphone version of the PDD. Taken together, we were able to construct a relatively brief self-report measure that assesses major dimensions of within- and between-person differences of situations and behaviors in daily life with acceptable reliability. Application in clinical samples provided further evidence for the reliability, validity, and clinical utility of the PDD but also highlighted possible obstacles in clinical practice as well as the need for further replication and refinement. We conclude that daily diary methods have the potential to integrate within- and between-person approaches to personality assessment. By applying measures like the PDD, clinicians may gain insight into the psychological mechanisms that give rise to, and maintain, a person's maladaptive dispositions and ultimately find individualized leverage points for targeted therapeutic interventions. (PsycINFO Database Record (c) 2019 APA, all rights reserved).