Overview
The Patient Health Questionnaire (PHQ) is a diagnostic tool for mental health disorders used by health care professionals (Pfizer 2017a). It consists of 5 scales covering depression, anxiety, somatoform, alcohol and eating. The PHQ is part of a family of related measures, including the PHQ-9, which is the depression scale from the PHQ, and the PHQ-15, which is the somatic symptom scale from the PHQ (Kroenke 2014).
Psychometric properties
A study of adult patients found good agreement between PHQ diagnoses and those of independent mental health professionals (Spitzer et al. 1999). No studies of the full PHQ’s reliability could be identified. However, studies of the reliability and validity of the PHQ-9 depression scale have been conducted (Kroenke et al. 2010).
Suitability
Participants in two studies to determine the validity and utility of the full PHQ ranged in age from 18 to 99 years (Spitzer et al. 1999, Spitzer et al. 2000). A study has looked at the usability of the PHQ-9 in an adolescent population (13-17 year olds) and concluded it is an excellent tool for screening depression with this age range in primary care settings (Richardson et al. (2010).
Translation
Available in English, Finnish for Finland, Czech for the Czech Republic, Danish for Denmark, Dutch for the Netherlands, French for Canada, French for France, German for Germany, Hebrew for Israel, Hungarian for Hungary, Italian for Italy, Korean for Korea, Malay for Malaysia, Mandarin for Malaysia, Norwegian for Norway, Polish for Poland, Portuguese for Brazil, Russian for Russia, Spanish for Spain, Spanish for the USA, Swedish for Sweden, Traditional Chinese for Hong Kong and Traditional Chinese for Taiwan (Pfizer 2017a).
Instructions for developing further translations can be obtained by emailing questions@phqscreeners.com (PHQ and GAD-7: Other translations 2010).
Administration
The PHQ is self-administered. Each PHQ module can be used alone (e.g. the PHQ-9 if depression is the condition of interest), together with other modules, or as part of the full PHQ (Kroenke 2014).It can be completed in session with a clinician and used to discuss how treatment is going.
Terms of use
Free for download and use as stated within the PHQ Screeners site (Pfizer 2017b). The text at the bottom of the PHQ form states that “No permission is required to reproduce, translate, display or distribute” (PHQ 2010).
Further information
The PHQ-A is a substantially modified version of the PHQ developed for use in adolescents (Kroenke 2014). Richardson et al. (2010) investigated the original version of the PHQ-9 in an adolescent population an found that a slightly higher cut-off (11 instead of 10 for adults) better distinguished between adolescents with a depressive disorder and those without.
References
Kroenke K (2014) Instruction Manual - Instructions for Patient Health Questionnaire (PHQ) and GAD-7 Measures (accessed 6 June 2017).
Kroenke K, Spitzer RL, Williams JBW, Löwe B (2010) The Patient Health Questionnaire Somatic, Anxiety, and Depressive Symptom Scales: a systematic review. General Hospital Psychiatry; 32: 345-59.
Pfizer (2017a) Welcome to the Patient Health Questionnaire (PHQ) Screeners (accessed 6 June 2017).
Pfizer (2017b) Terms of Use. (accessed 6 June 2017).
PHQ - Patient Health Questionnaire (2010) (accessed 6 June 2017).
PHQ and GAD-7: Other translations (2010) (accessed 6 June 2017).
Richardson, L.P., McCauley, E., Grossman, D.C., McCarty, C.A., Richards, J., Russo, J.E., Rockhill, C., & Katon, W. (2010). Evaluation of the Patient Health Questionnaire-9 Item for Detecting Major Depression Among Adolescents. Pediatrics, 126(6), 1117-1123.
Spitzer RL, Kroenke K, Williams JBW, Patient Health Questionnaire Primary Care Study Group (1999) Validation and Utility of a Self-report Version of PRIME-MD - The PHQ Primary Care Study. JAMA; 282(18): 1737-44
Spitzer RL, Williams JBW, Kroenke K, Hornyak R, McMurray J, Patient Health Questionnaire Obstetrics-Gynecology Study Group (2000) Validity and utility of the PRIME-MD Patient Health Questionnaire in assessment of 3000 obstetric-gynecologic patients: The PRIME-MD Patient Health Questionnaire Obstetrics-Gynecology Study. American Journal of Obstetrics and Gynecology; 183(3): 759-69.