Self-Reported Depressive Symptom Measures: Sensitivity to Detecting Change in a Randomized, Controlled Trial of Chronically Depressed, Nonpsychotic Outpatients

This study evaluated and compared the performance of three self-report measures: (1) 30-item Inventory of Depressive Symptomatology-Self-Report (IDS-SR30); (2) 16-item Quick Inventory of Depressive Symptomatology-Self-Report (QIDS-SR16); and (3) Patient Global Impression-Improvement (PGI-I) in assessing clinical outcomes in depressed patients during a 12-week, acute phase, randomized, controlled trial comparing nefazodone, cognitive-behavioral analysis system of psychotherapy (CBASP), and the combination in the treatment of chronic depression. The IDS-SR30, QIDS-SR16, PGI-I, and the 24-item Hamilton Depression Rating Scale (HDRS24) ratings were collected at baseline and at weeks 1-4, 6, 8, 10, and 12. Response was defined a priori as a > or =50% reduction in baseline total score for the IDS-SR30 or for the QIDS-SR16 or as a PGI-I score of 1 or 2 at exit. Overall response rates (LOCF) to nefazodone were 41% (IDS-SR30), 45% (QIDS-SR16), 53% (PCI-I), and 47% (HDRS17). For CBASP, response rates were 41% (IDS-SR30), 45% (QIDS-SR16), 48% (PGI-I), and 46% (HDRS17). For the combination, response rates were 68% (IDS-SR30 and QIDS-SR16), 73% (PGI-I), and 76% (HDRS17). Similarly, remission rates were comparable for nefazodone (IDS-SR30=32%, QIDS-SR16=28%, PGI-I=22%, HDRS17=30%), for CBASP (IDS-SR30=32%, QIDS-SR16=30%, PGI-I=21%, HDRS17=32%), and for the combination (IDS-SR30=52%, QIDS-SR16=50%, PGI-I=25%, HDRS17=49%). Both the IDS-SR30 and QIDS-SR16 closely mirrored and confirmed findings based on the HDRS24. These findings raise the possibility that these two self-reports could provide cost- and time-efficient substitutes for clinician ratings in treatment trials of outpatients with nonpsychotic MDD without cognitive impairment. Global patient ratings such as the PGI-I, as opposed to specific item-based ratings, provide less valid findings.