title: Validation of the Patient Health Questionnaire-9 for Major Depressive Disorder in the Occupational Health Setting.
abstract: Purpose Because of the increased risk of long-term sickness leave for employees with a major depressive disorder (MDD), it is important for occupational health professionals to recognize depression in a timely manner. The Patient Health Questionnaire-9 (PHQ-9) has proven to be a reliable and valid instrument for screening MDD, but has not been validated in the occupational health setting. The aim of this study was to validate the PHQ-9 for MDD within a population of employees on sickness leave by using the MINI-International Neuropsychiatric Interview (MINI) as a gold standard. Methods Participants were recruited in collaboration with the occupational health service. The study sample consisted of 170 employees on sickness leave between 4 and 26 weeks who completed the PHQ-9 and were evaluated with the MINI by telephone. Sensitivity, specificity, positive and negative predictive value, efficiency and 95 % confidence intervals (95 % CIs) were calculated for all possible cut-off values. A receiver operator characteristics (ROC) analysis was computed for PHQ-9 score versus the MINI. Results The optimal cut-off value of the PHQ-9 was 10. This resulted in a sensitivity of 86.1 % [95 % CI (69.7-94.8)] and a specificity of 78.4 % [95 % CI (70.2-84.8)]. Based on the ROC analysis, the area under the curve for the PHQ-9 was 0.90 [SE = 0.02; 95 % CI (0.85-0.94)]. Conclusion The PHQ-9 shows good sensitivity and specificity as a screener for MDD within a population of employees on sickness leave.
authors.affiliation: Trimbos-Institute, Netherlands Institute of Mental Health and Addiction, PO Box 725, 3500 AS, Utrecht, The Netherlands. dvolker@trimbos.nl.|Tranzo, Tilburg University, Tilburg, The Netherlands. dvolker@trimbos.nl.
authors.forename: D
authors.initials: D
authors.lastname: Volker
authors.affiliation: Trimbos-Institute, Netherlands Institute of Mental Health and Addiction, PO Box 725, 3500 AS, Utrecht, The Netherlands.
authors.forename: M C
authors.initials: MC
authors.lastname: Zijlstra-Vlasveld
authors.affiliation: Tranzo, Tilburg University, Tilburg, The Netherlands.
authors.forename: E P M
authors.initials: EP
authors.lastname: Brouwers
authors.affiliation: Bureau HHM, Enschede, The Netherlands.
authors.forename: W A
authors.initials: WA
authors.lastname: Homans
authors.affiliation: Department of Methodology and Statistics, Tilburg University, Tilburg, The Netherlands.
authors.forename: W H M
authors.initials: WH
authors.lastname: Emons
authors.affiliation: Tranzo, Tilburg University, Tilburg, The Netherlands.|Top Clinical Centre for Body, Mind and Health, GGZ Breburg, Tilburg, The Netherlands.
authors.forename: C M
authors.initials: CM
authors.lastname: van der Feltz-Cornelis
mesh_terms: D000328:Adult; D000368:Aged; D003863:Depression / Q000175:diagnosis / Q000523:psychology; D003865:Major Depressive Disorder / Q000175:diagnosis*; D006801:Humans; D008403:Mass Screening / Q000295:instrumentation*; D008875:Middle Aged; D016272:Occupational Health; D009786:Occupational Health Services; D012372:ROC Curve; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018582:Sick Leave; D011795:Surveys and Questionnaires / Q000592:standards*
keywords: Major depressive disorder; Occupational health setting; PHQ-9; Validation study