Presenting Author(s) Names: Dr. Kimberly Williams, Mr. Michael Sanderson, Dr. Nathalie Jette, and Dr. Scott B Patten
Sijonnesen, K., Berzins, S., Fiest, K., Bulloch, A., Metz, L., Thombs, D., & Patten, S. (2015). Evaluation of the 9-Item Patient Health Questionnaire (PHQ-() as an assessment instrument for symptoms of depression in patients with multiple sclerosis. Post-Graduate Medicine, 124 (5), 69-77.
Fiest, K., Patten, S., Wiebe, S., Bulloch, A., Maxwell, C., & Jette, N. (2014). Validating screening tools for depression in epilepsy. Epilepsia, 10.1111/epi.12754.
Introduction: Due to symptom overlap, there is uncertainty about the validity of depression rating scales in neurological populations.
Rationale: The objectives of this study was to evaluate the validity of the Patient Health Questionaire-9 (PHQ-9) for detecting Diagnostic and Statistical Manual (DSM)-defined major depressive episodes in people with neurological conditions.
Methods: Participants were recruited from outpatient clinics for Multiple Sclerosis, epilepsy, migraine, Parkinson’s Disease and stroke. Participants were administered a questionnaire (this included the PHQ-9), chart review and a follow up telephone interview. The Structured Clinical Interview for Depression was used as the reference standard for psychiatric diagnoses. The performance of PHQ-9 was analyzed using sensitivity, specificity, diagnostic odds ratios (DOR) and receiver operator curve analysis.
Results: All neurological subpopulations had a specificity greater than 78% and sensitivity greater than 79% at a cut point of 10. Using a random effects model the I2 value was 13.7% and Tau2 was 0.05, showing homogeneity across the neurological subpopulations. The pooled DOR was 25.3 (95%CI 14.9 – 42.8). Meta-analytic analysis for sensitivity found the pooled estimate was 90% (95%CI 81-97) and for specificity was 85% (95%CI 79-90).
Discussion: Despite theoretical concerns about its validity, the PHQ-9 performed well at its standard cut-point of 10. Consistent with literature, being able to use a validated, brief tool which is available publically should improve case finding of depression in neurological populations.
Conclusions: When considering clinical practicality along with the findings of this analyzed this study confirmed that the PHQ-9 is valid in a general outpatient neurological population.