Patient Health Questionnaire – 9 (PHQ-9)
The Patient Health Questionnaire – 9 (PHQ-9) is a short self-report questionnaire with 9 items that correspond to the DSM-IV diagnostic criteria for depressive disorder. This is a depression module extracted from the entire PHQ questionnaire, which is used to determine the severity of depression and depressive symptoms. Items ask about the frequency of experiences in the past two weeks.
Length of filling
The PHQ-9 takes approximately 3 minutes to complete.
Individualized feedback for the respondent
After evaluating the questionnaire, the test subject will find out the severity of depression or depressive symptoms.
Keywords
Patient Health Questionnaire, PHQ-9, depression, depressive disorder, depressive symptoms
Scoring and interpretation
When determining the PHQ-9 score, each individual symptom is coded as 0, 1, 2, or 3, and the total score obtained by summing the points ranges from 0 to 27. Higher scores indicate more severe depressive symptoms.
Response scale
Respondents rate the items on a scale from 0 to 3 according to the frequency of their experiences in the previous two-week period (0=Not at all, 1=Several days, 2=More than half the days, 3=Almost every day).
References
Daňsová, P., Masopustová, Z., Hanáčková, V., Kicková, K., & Korábová, I. (2016). Metoda Patient Health Questionnaire-9: Česká verze. Československá psychologie, 60(5), 468-481. https://www.researchgate.net/publication/313602110_The_patient_health_questionnaire-9_The_Czech_version
Haddad, M., Walters, P., Phillips, R., Tsakok, J., Williams, P., Mann, A., & Tylee, A. (2013). Detecting depression in patients with coronary heart disease: a diagnostic evaluation of the PHQ-9 and HADS-D in primary care, findings from the UPBEAT-UK study. PloS one, 8(10), e78493. https://doi.org/10.1371/journal.pone.0078493
Kroenke, K., & Spitzer, R. L. (2002). The PHQ-9: A new depression diagnostic and severity measure. Psychiatric Annals, 32(9), 509–515. https://doi.org/10.3928/0048-5713-20020901-06
Kroenke, K., Spitzer, R. L., & Williams, J. B. W. (2001). The PHQ-9: Validity of a brief depression severity measure. Journal of General Internal Medicine, 16(9), 606–613. https://doi.org/10.1046/j.1525-1497.2001.016009606.x