Key references:
Kroenke, K., Spitzer, R. L., Williams, J. B. W., Löwe, B. (2009). An ultra-brief screening scale for anxiety and depression: the PHQ-4 Psychosomatics, 50, 613-621.
Primary use / Purpose:
Background:
Anxiety and depression are the two most prevalent illnesses among patients, and in the general population. Because these two mood disorders are frequently co-morbid they can have especially problematic outcomes. The nature of these mood disorders can make filling out long questionnaires difficult if patients are suffering from fatigue or loss of concentration. Furthermore, time is at a premium in any clinical practice. Therefore, the 'Patient Health Questionnaire-4' (PHQ-4) was developed and validated by Kroenke, Spitzer, Williams, & Löwe, (2009) in order to address these needs
Psychometrics:
The psychometric propertie of the 'Patient Health Questionnaire-4' (PHQ-4) are discussed in Kroenke, Spitzer, Williams, & Löwe, (2009)