Fragebogen zur Gesundheit des Patienten

This easy to use patient questionnaire is a self-administered version of the PRIME-MD diagnostic instrument for common mental disorders.¹ The PHQ-9 is the depression module, which scores each of the nine DSM-IV criteria as "0" (not at all) to "3" (nearly every day). It has been validated for use in primary care.²

It is not a screening tool for depression but it is used to monitor the severity of depression and response to treatment. However, it can be used to make a tentative diagnosis of depression in at-risk populations - eg, those with coronary heart disease or after stroke.³⁴

When screening for depression the Patient Health Questionnaire (PHQ-2) can be used first (it has a 97% sensitivity and a 67% specificity).⁵ If this is positive, the PHQ-9 can then be used, which has 61% sensitivity and 94% specificity in adults.

Patient Health Questionnaire (PHQ-9)

Validity has been assessed against an independent structured mental health professional (MHP) interview. PHQ-9 score ≥10 had a sensitivity of 88% and a specificity of 88% for major depression.¹ It can even be used over the telephone.⁶

The copyright for the PHQ-9 was formerly held with Pfizer, who provided the educational grant for Drs Spitzer, Williams and Kroenke who originally designed it.¹This is no longer the case and no permission is required to reproduce, translate, display or distribute the PHQ-9.