Table 1.
Descriptions of measures (QIDS-SR, WSAS, and Q-LES-Q)
| Measure (Reference) | Description | Validity and reliability |
|---|---|---|
| Quick Inventory of Depressive Symptomatology—Self Report or QIDS-SR (Rush et al. 2003) | A 16-item self-administered instrument that covers the nine DSM-IV criterion symptoms for major depressive disorder. It has been used in a variety of research and clinical settings, e.g., as an outcome measure in industry-sponsored randomized clinical trials, as well as in outpatient psychiatric and primary care clinics. | Good internal consistency and reliability has been reported for clinical populations with very high concurrent validity found between QIDS-SR and the HSRD in three large independent patient samples. It takes 5–10 min to complete, and has the advantage of providing a single numerical score for depression severity based on numerical score while having similar sensitivity to change as the HSRD in a clinical trial of chronic major depression. |
| Work and Social Adjustment Scale or WSAS (Mundt et al. 2002) | A five-item self-report scale of functional impairment attributable to an identified problem that is easy for patients to understand and complete. | Internal consistency is very good in depressed patients, with a Cronbach's α coefficient of 0.807 at baseline that increases with time up to 0.942 at week 30. There is also good convergent validity with HSRD-17, with a correlation coefficient of 0.76. Additionally, strong criterion validity (ability to stratify among different levels of severity) was established by association with HSRD severity strata. |
| Quality of Life Enjoyment and Satisfaction Questionnaire—Short Form or Q-LES-Q (Endicott et al., 1993) | A self-administered quality of life instrument that was designed to obtain sensitive information on the degree of enjoyment and satisfaction experienced by patients in various areas of daily functioning. The long form consists of 60 items and 5 subscales, whereas the short form consists of 16 items. The short form was used for the purpose of this study. | Q-LES-Q was shown to have a reliability coefficient of 0.90–0.96 for subscales and 0.90 for the summary scale, and a test–retest coefficient of 0.63–0.89 for subscales and 0.74 for summary scale. A correlation coefficient of −0.62 between the summary scale and the Clinical Global Impression (CGI) scale supports its convergent validity. |