Reliability of psychological evaluation in chronic pain in an interventional pain management setting.

BACKGROUND: Psychological disorders may be associated with poor pain related treatment outcomes. However, there may be limitations with studies evaluating the relationship between pain and psychopathology. OBJECTIVE: To assess the reliability of psychological evaluations in interventional pain management by MCMI-III(R) and P-3(R). STUDY DESIGN: Prospective evaluation of consecutive patients in an interventional pain management center. METHODS: Patients were evaluated using a DSM-IV-TR(R) questionnaire with a physician interview as an integral part of their comprehensive evaluation. In addition, all the patients participating in this study also underwent psychological evaluation with MCMI-III and P-3. A positive diagnosis of major depression or generalized anxiety disorder based on DSM-IV-TR criteria was considered as the criterion standard. All of the patients presented for treatment of chronic pain. The data based on the criterion standard were compared with results of the diagnostic impression from the MCMI-III and the P-3 evaluation utilizing criteria for average, and above average, patient pain scores. RESULTS: Major depression was diagnosed in a total of 59 of 100 patients using DSM-IV-TR criteria, in 32 patients based on MCMI-III criteria, and in 55 patients based on P-3 evaluations utilizing average pain patient criteria. Generalized anxiety disorder was diagnosed in 55 patients by means of DSM-IV-TR, 45 patients by MCMI-III, and 55 patients by P-3 Profile utilizing average pain patient scores. The specificity of MCMI-III was 100% with a sensitivity of 54% for diagnosis of depression; whereas it was 78% specificity and sensitivity for P-3, with average pain patient scores. For generalized anxiety disorder, specificity of MCMI-III was 89% with a sensitivity of 73% compared to specificity of 80% and sensitivity of 84% for average pain patient scores for P-3. CONCLUSION: MCMI-III and P-3 are highly specific in diagnosing depression and generalized anxiety disorder, with variable sensitivity. A DSM-IV-TR questionnaire evaluation incorporated into the pain management questionnaire, along with a short clinical interview, is a reliable means of assessing depression and anxiety in patients suffering with chronic pain.