The Effectiveness of Psychotherapeutic Treatments for Personality Disorders: A Review and Critique of Current Research Practices

Randomized clinical trials (RCTs) are the primary mechanism through which treatments are determined to reduce symptoms for personality disorders (PDs). Evidence regarding treatments for PDs indicates that the effect sizes for PD psychotherapy treatments are large, leading researchers to conclude that psychotherapy treatments reduce PD symptomology. However, these conclusions can be misleading in light of theoretical and methodological concerns related to PDs and their treatments. The primary concerns that exist for testing the effectiveness of treatments for PDs include an unsound theoretical basis for PDs that impact the measurement and testing of psychotherapy treatments. Evidence of high comorbidity rates of PDs with other PDs and psychiatric diagnoses are indicative of incorrect classification of diagnostic criteria. Additionally, clinician bias when diagnosing PDs can impact the inclusion of participants into RCTs testing psychotherapy treatments. Finally, criticisms of how RCTs measure outcomes related to PDs are included, such as using symptom measures for other diagnoses to indicate the effectiveness of a treatment for a PD diagnosis. Recommendations are offered to enhance the ways in which RCTs test psychotherapy treatments for PDs, including theory that can be empirically tested for PDs, training researchers and clinicians about diagnostic bias related to PDs, and creating and implementing valid targeted measures that test the effectiveness of psychotherapy treatments that are specific to PDs.Keywords: personality disorders, randomized clinical trials, personality assessment, diagnostic bias, comorbidityResumeLes essais cliniques aleatoires (ECA) sont le principal moyen de determiner les traitements visant a reduire les symptomes des troubles de la personnalite (TP). Les preuves au sujet des traitements pour les TP indiquent que l'ampleur de l'effet de la psychotherapie est significative, ce qui a permis aux chercheurs de conclure que celle-ci reduit les symptomes associes aux TP. Toutefois, ces conclusions peuvent etre trompeuses lorsqu'on tient compte des preoccupations d'ordre theorique et methodologique reliees aux TP et a leur traitement. Parmi les principales preoccupations figure le fait que l'evaluation de l'efficacite des traitements pour les TP se fonde en partie sur une base theorique incorrecte, ce qui influe sur la mesure et l'essai des traitements au moyen de la psychotherapie. Des taux eleves de comorbidite avec d'autres TP ainsi que des diagnostics psychiatriques revelent une classification incorrecte des criteres de diagnostic. De plus, le biais du clinicien durant le diagnostic des TP peut influer sur le choix des participants a des ECA pour l'evaluation de la psychotherapie a titre de traitement. L'article se termine par une critique de la facon dont sont mesures les resultats des ECA en ce qui a trait aux TP, comme l'usage de mesures de symptomes d'autres diagnostics pour indiquer l'efficacite d'un traitement de TP. Suivent des recommandations visant a ameliorer l'evaluation d'ECA de psychotherapies pour TP, qui incluent le recours a des fondements theoriques pouvant etre testes empiriquement, la formation des chercheurs et des cliniciens afin qu'ils reconnaissent les biais dans le diagnostic de TP ainsi que la creation et l'application de mesures valides ciblees pour evaluer l'efficacite de la psychotherapie propre au traitement des TP.Mots-cles : troubles de la personnalitee, essais cliniques aleatoires, evaluation de la personnalite, biais de diagnostic, comorbidite.Randomized clinical trials (RCTs) are the primary mechanism through which treatments are determined to reduce symptoms for PDs. To date, a debate continues as to whether RCTs (derived from a medical model) establish which psychotherapy treatments are more effective than others or whether most treatments are equally effective (Wampold, 2001). Though numerous studies have been conducted regarding the efficacy and effectiveness of treatments for personality disorders (PDs), the equality of PD treatments continues to be unknown. …