Measuring Depression and Anxiety With 4 Items? Adaptation of the PHQ-4 to Increase Its Sensitivity to Subclinical Variability

Abstract

The PHQ-4 is an ultra-brief screening questionnaire for depression and anxiety. This brief report tests whether adding one additional response option, once or twice, between not at all and several days improves the scale’s sensitivity to milder alterations and increases its usefulness in subclinical populations. A pilot study showed prevalent use of the new response option, and a follow-up validation study confirmed that the refined version offered improved sensitivity to subclinical variability in depression compared with the original version. The findings suggest that adding the once-or-twice response option is a low-cost way to increase the PHQ-4’s sensitivity for general population research.