A Comparison of the QIDS-C16, QIDS-SR16, and the MADRS in an Adult Outpatient Clinical Sample.

Background : This study compared the 16-item Clinician and Self-Report versions of the Quick Inventory of Depressive Symptomatology (QIDS-C 16 and QIDS-SR 16 ) and the 10-item Montgomery-Asberg Depression Rating Scale (MADRS) in adult outpatients. The comparison was based on psychometric features and their performance in identifying those in a major depressive episode as defined by the Mini-International Neuropsychiatric Interview for Diagnostic and Statistical Manual of Mental Disorders , Fourth Edition. Methods : Of 278 consecutive outpatients, 181 were depressed. Classical test theory, factor analysis, and item response theory were used to evaluate the psychometric features and receiver operating characteristic (ROC) analyses. Results : All three measures were unidimensional. All had acceptable reliability (coefficient α =.87 for MADRS 10 , .82 for QIDS-C 16 , and .80 for QIDS-SR 16 ). Test information function was higher for the MADRS (ie, it was most sensitive to individual differences in levels of depression). The MADRS and QIDS-C 16 slightly but consistently outperformed the QIDS-SR 16 in differentiating between depressed versus non-depressed patients. Conclusion : All three measures have satisfactory psychometric properties and are valid screening tools for a major depressive episode.