The PHQ-9 is used to monitor the severity of depression and response to treatment. It is not a screening tool for depression however, it can be used to make a tentative diagnosis of depression in at-risk populations, such as those with coronary heart disease or after stroke. It 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.
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. This is no longer the case and no permission is required to reproduce, translate, display or distribute the PHQ-9.
The scale scores “0” for “not at all”, “1” for “several days”, “2” for “more than half the days” and “3” for “nearly every day”.
Depression Severity: 0-4 none, 5-9 mild, 10-14 moderate, 15-19 moderately severe, 20-27 severe.