Patient Health Questionnaire-2 (PHQ-2)
Ultra-brief screening for depressive disorders
The Patient Health Questionnaires (PHQ-2) was developed by Drs. Robert L. Spitzer, Janet B.W. Williams, Kurt Kroenke and colleagues, with an educational grant from Pfizer, Inc. The Patient Health Questionnaires originated from The Primary Care Evaluation of Mental Disorders (PRIME-MD) which was an questionnaire developed and validated in the early 1990s to efficiently diagnose five of the most common types of mental disorders presenting in medical populations: depressive, anxiety, somatoform, alcohol, and eating disorders.
The PRIME-MD was too lengthy for screenings, which led to the creation of the PHQ-9, which contains nine questions. However, still not brief enough for screening; it was shorten to the PHQ-2 which are actually the first two questions of the PHQ-9. These two questions are also the level A criterion for the diagnostic criteria to Major Depressive Disorder in the Diagnostic and Statistical Manual of Mental Disorders.
Although screening for unipolar depression is controversial, it is potentially an efficient way to find undetected patients if followed up with additional investigation. Since the PHQ-2 is well studied, it has a reference standard, making it useful in primary care.
If the total score is greater than three then it’s considered positive and warrants further diagnostic investigation, which is often followed up by the Patient Health Questionnaires (PHQ-9).
In order to make this screening tool useful keep in mind it’s optimal to select a population with a high prevalence, and to have a high enough sensitivity full well knowing that there will false positives.
Elevated scores can be positive for disorder such as but not limited to Bipolar I, Bipolar II, Cyclothymia, Dysthymia, or Personality Disorders. Patients should also be informed that a negative screening result does not mean disease is not present, but rather the likelihood of disease is low.
Spitzer RL, Williams JBW, Kroenke K, Linzer M, deGruy FV, Hahn SR, Brody D, Johnson JG.
Spitzer RL, Kroenke K, Williams JBW.
Arroll B, Goodyear-smith F, Crengle S, et al.
Kroenke K, Spitzer RL, Williams JB.