Individuals largely misinterpret the instructions when completing the most commonly used depression screening tool, the PHQ (Patient Health Questionnaire), raising concerns about its validity, according to a study published by JAMA Psychiatry.
Why It’s Important
Self-reported depression measures, particularly the PHQ series (e.g. PHQ-2, PHQ-8, and PHQ-9) have become increasingly common in clinical practice and research because they offer accessible and low-cost screening. However, important questions remain about the PHQ series’ accuracy and validity, particularly whether participants’ responses should reflect symptom frequency or the degree to which symptoms are bothersome, as its creators intend.
By the Numbers
- Among 503 adults in the general population and 349 individuals with moderate to severe depression who completed the PHQ-8 for this survey study, just 21% and 12%, respectively, interpreted the instructions correctly.
- Given a hypothetical scenario in which the respondent overslept nearly every day but was comfortable with that, 55% of the general population and 16% of the clinically depressed participants interpreted the PHQ sleep question as intended.
- In the clinical sample, the correlation between individuals’ responses to PHQ-8 questions and similar questions on another screening tool—the 15-item Quick Inventory of Depressive Symptomatology—was different for those who focused on frequency versus being bothered.
What’s More
After being asked to reflect on the difference between “frequency” and “bothersome,” just 22% of the general population and 10% of the clinical sample said they would focus on the latter in the future.
The Other Side
The findings need to be externally validated and replicated in other populations, settings (for example, inpatient or primary care), and languages. This study also used a slightly adapted version of the original PHQ-8.
Takeaway Message
“The current findings highlight longstanding problems in self-report mental health assessment, including limited attention to instructions, an overemphasis on psychometric testing at the expense of validity, minimal user involvement in measure development, and continued reliance on outdated tools in urgent need of revision,” the researchers wrote.
Related Information
Source
Margarita Panayiotou, Ph.D., et al. Interpretation issues with the Patient Health Questionnaire instructions. JAMA Psychiatry. Published December 17, 2025. doi: 10.1001/jamapsychiatry.2025.3796
