Recognizing signs of mental health disorders is not always easy. The Patient Health Questionnaire (PHQ) is a diagnostic tool for mental health disorders used by health care professionals that is quick and easy for patients to complete. In the mid-1990s, Robert L. Spitzer, MD, Kurt Kroenke, MD, and colleagues at Columbia University developed the Primary Care Evaluation of Mental Disorders (PRIME-MD), a diagnostic tool containing modules on 12 different mental health disorders. They worked in collaboration with researchers at the Regenstrief Institute at Indiana University and with the support of an educational grant from Pfizer Inc. During the development of PRIME-MD, Drs. Spitzer and Kroenke, together with Janet B.W. Williams, DSW, at Columbia University, created the PHQ screeners.

The PHQ, a self-administered version of the PRIME-MD, contains only the mood, anxiety, and some of the sleep disorder modules as covered in the original PRIME-MD. This tool assesses the 15 most common physical symptoms in primary care. A shorter, alternative version of the PHQ, called the Brief PHQ, assesses depression, anxiety, psychological stressors, and women's reproductive health. The PHQ-9, a tool specific to depression, simply scores each of the 9 DSM-IV criteria based on the mood module from the original PRIME-MD.

Please note: The PHQ-9 translations from English into their respective languages have not been validated as depression screeners.