The PHQ-2 has been presented as an ultra-short screening questionnaire to detect depression in several healthcare settings. It consists of two questions on low mood and anhedonia, both questions being derived from the more accurate PHQ-9. The PHQ-2 is to be used as an initial screening tool for patients with possible depression, which can then be evaluated in more detail using other tools, such as the PHQ-9. The PHQ-2 is both reliable and valid as a screening tool. Sensitivity and specificity do depend on the threshold score used in evaluating the PHQ-2. When a threshold of three is used, the PHQ-2 is highly specific, but with lower sensitivity. The PHQ-2 is not currently used as widely as it could be and, in many situations, depression continues to be underdiagnosed. We hypothesize that, if used routinely in several situations, the identification of depression would be much improved.
Keywords: depression, PHQ-2 screening