A new study calls into question the validity of the Patient Health Questionnaire (PHQ), a foremost depression screening tool, and cautions researchers and mental health providers about relying on PHQ results.
A new research report suggests that a widely used depression screening questionnaire should not be relied on for research purposes or in assessments for depression.
A team of academic researchers investigated the validity of the Patient Health Questionnaire (PHQ), whose various versions are among the most widely used tools in research and clinical settings worldwide for assessing depression in patients. The researchers’ particular concern was whether responses to PHQ questions reflected how often potential symptoms of depression were experienced, or how much those symptoms bothered the individuals. The PHQ instructions ask for how often the symptoms bother the person.
The study’s findings, reported in JAMA Psychiatry, indicated that fewer than one in five responded to the PHQ according to the instructions (i.e., how much the symptoms bothered them). Instead, their answers more often reflected the frequency, not severity of symptoms. The scoring resulting from those responses likely indicated more severe depression than was actually the case.
“Results of this study suggest that the PHQ is widely misinterpreted, raising concerns about its validity for research and clinical decision-making,” the report says.
Conditions the PHQ asks about – such as having “little interest or pleasure in doing things,” “feeling down,” “feeling tired or having little energy,” and “poor appetite or overeating” – may be felt by many people in the normal course of living.
