How Much Training Do We Need? Assessing the Validity and Interrater Reliability of the PDM-2’s Psychodiagnostic Chart among Less Experienced Clinicians

Abstract

The Psychodynamic Diagnostic Manual – Second Edition (PDM-2) has emerging evidence supporting its clinical utility, yet one of the main limitations remains the conjecture that considerable training and experience is required. It also remains unclear how the PDM-2 framework compares with current DSM measures of personality pathology such as the Level of Personality Functioning Scale (LPFS). The aim of the present study is to examine these issues by testing whether less clinically experienced second year doctoral psychology students are able to reliably assess patients’ level of personality pathology using the PDM-2’s Psychodiagnostic Chart (PDC-2), and to investigate the convergence between the PDC-2 and the LPFS. Results showed adequate inter-rater reliability for both of the main PDC-2 axes, with 52% of the variance for the overall personality organization (P-Axis) rating, and 29% of the overall M-Axis score being due to rater consensus. Reliability of individual ratings ranged from fair to excellent for the overall scores on both axes (ICC = 0.59 to .90). Results also showed that student evaluations were valid, with the latter’s assessment of the patients’ level of personality organization converging both with the experts’ rating of the PDC-2 as well as the LPFS. Implications for clinical training are discussed.