Everybody gets better, same but different? A review and meta-analysis of changes in defense mechanisms in psychotherapy studies of patients with PD vs. non-PD and its predictive value for therapy outcome

Objective: Defenses are fundamental mechanisms that underlie basic personality functioning, affecting both symptom disorders and adaptation. One of the original constructs in psychodynamic theory (1894), the study of defense mechanisms has continued to flourish in both clinical and research arenas. This report examines those studies that have measured change in defenses in adults with psychotherapy in relationship to other outcomes for a variety of diagnoses and treatment types. Methods: We located 12 studies (6 PD-, 6 non-PD studies) that met our inclusion criteria for psychotherapy studies, using a standardized assessment method for rating defenses before or during therapy and afterward, thus allowing the calculation of raw change and effect size, as well as reporting other outcomes. Results / Discussion: Studies used one observer-rated methods, the Defense Mechanisms Rating Scales (DMRS) and one self-report method, the Defense Style Questionnaire (DSQ). Studies reported results for individual defenses, defense levels, defense styles and Overall Defensive Functioning (ODF), indicating the average level of adaptiveness. Overall Defensive Functioning improved significantly in 70% of the studies. Differences in rate of change for patients with PD vs. non-PD will be discussed. Findings converged with changes in other outcome measures e.g. symptoms and measures of global and social role functioning. Conclusion: Shorter therapies were associated with smaller improvements in defensive functioning, while longer duration treatments were associated with larger effect sizes. We will discuss the implications for clinicians working with defenses, and make recommendations for future research