Can 3 Questions Flag Depression? PHQ-3 Tested

A brief, 3-question version of the widely used Patient Health Questionnaire-9 (PHQ-9) may provide a faster, yet still accurate, way for physicians to screen for depression, new research suggests. 

In a study of more than 96,000 US adult participants, the PHQ-3 had 98% sensitivity and 76% specificity for predicting at least moderate or greater depressive symptoms. 

Additionally, it was “highly correlated” with the full PHQ-9 and noninferior to a recently validated 4-item version for effectiveness — and it yielded a sensitivity of more than 90% across all ages, races, and ethnicities. 

Lead investigator Roy H. Perlis, MD, vice chair of research in the Department of Psychiatry at Mass General Brigham in Boston, said the team set out to identify the shortest version of the PHQ-9 that could still effectively screen for depression — and found that the PHQ-3 hit the “sweet spot.”

“We let the data tell us what the constellation of symptoms are that best predict overall severity and how well they do at identifying depression. It’s a way we might be able to get the maximum amount of information in the shortest amount of time,” Perlis told Medscape Medical News. 

However, he noted that he’s not yet ready to endorse the PHQ-3 for use in clinical practice. 

“I want to see further studies in clinical settings. But I think we made a good start towards showing it did well in a big, general sample of US adults,” Perlis said. 

The findings were published online on July 21 in JAMA Network Open. 

Shorter Attention Spans

“The PHQ-9 was not intended as a tool to diagnose depression. It’s just a way to start the conversation; and although it’s not perfect, it is useful,” Perlis noted. 

The original patient-reported PHQ screens for depression, anxiety, eating disorders, alcohol misuse, and somatization. Its 9-item depression scale (PHQ-9) became widely used to identify depression along with related symptoms such as fatigue and sleep disturbances.

However, the length of the questionnaire has become burdensome for some patients, particularly those who prefer using phone apps over printed forms. “Faced with a long list of survey questions, some individuals may be tempted to speed through or to not respond at all,” the investigators wrote.

At the recent American Psychiatric Association (APA) annual meeting, clinicians in the audience at several sessions mentioned that their patients have been complaining that the PHQ-9 is too long and that they prefer data to be delivered in smaller “chunks.”

Perlis said that attitude was a big motivator for the study. “We’re in an era where we have shorter attention spans and people want things very quickly,” he said.

“Personally, I would always rather have the PHQ-9. The question we were trying to answer was: Can we ask fewer questions if we don’t have the time or the space to ask about nine [items] and do almost as well?” Perlis said. 

The researchers assessed data from four waves of an online survey conducted from November 2023 to July 2024. In the first wave, they identified the optimal questionnaire items to be included. 

The four waves had a total of 96,234 participants (57% women; mean age, 47.3 years). Of these, 68% were White, 13% were Black, 10% were Hispanic or Latino, 5% were Asian, and 4% were classified as “other.” 

In the full patient population, 26% had moderate or greater depressive symptoms, as measured by a PHQ-9 score ≥ 10. 

Follow-up Is Key

After examining shortened versions of the PHQ-9 that ranged from including just one item up to eight items, the PHQ-3 with items 1 (interest), 2 (depressed mood), and 6 (self-esteem or failure) was deemed to be the “optimal” version.

It had a sensitivity of 0.98 (95% CI, 0.97-0.98) and a specificity of 0.76 (95% CI, 0.75-0.76) for moderate or greater depressive symptoms. 

Across all subgroups except participants aged 65 years or older, the sensitivity for the PHQ-3 was greater than 0.94. For that subgroup, it was 0.93. 

The PHQ-3 was also noninferior to previously reported sensitivity and specificity of the PHQ-Depression-4 in the whole study group and in all subgroups. 

The area under the receiver operating characteristic curve (AUROC) for predicting moderate or greater depressive symptoms was 0.83 for the PHQ-3. The AUROC for the PHQ-9 was 0.84. 

“While a shortened scale cannot capture the full range of the PHQ-9, it may facilitate more widespread and efficient investigation of psychiatric symptoms in general population samples when participant burden and/or data collection expense must be minimized,” the investigators wrote. 

Overall, Perlis said the PHQ-3 could be a possible first-step screening tool, with more questions added as needed. 

“What’s most important is that people are screening for depression and, if someone screens positive, that they’re following up with a more comprehensive evaluation and offering treatment if it’s indicated,” he said. “It’s really about figuring out who needs follow-up.”

Menu of Options?

In an accompanying editorial, Kurt Kroenke, MD, of Regenstrief Institute, Indianapolis, Indiana, noted that the study had “numerous strengths,” including its large and diverse study population, as well as several limitations.

First, the criteria for calculating sensitivity and specificity did not include a structured psychiatric interview — the standard used in previous evaluations of the 2- and 4-item PHQs. In addition, because the researchers drew from a general population sample, future studies should focus on actual patients in both primary care and psychiatric settings, Kroenke suggested. 

He noted that, in addition to the various shortened PHQs, the 2-item and 4-item versions of the Patient-Reported Outcomes Measurement Information System (PROMIS) have also demonstrated benefit.

“Clinicians and researchers looking for ultrashort depression measures now have a menu from which to choose, which is good since one size may not fit all purposes,” Kroenke wrote.

“Expanded use of brief screeners to increase detection of depression has the potential to decrease the burden of the most prevalent mental disorder worldwide,” he added. 

This study was funded in part by the National Science Foundation and the National Institutes of Health (NIH). Perlis reports receiving scientific advising fees from Genomind, Circular Genomics, and Alkermes. The disclosures of the other investigators can be found in the original paper. Kroenke reports he is a co-developer of the PHQ-9.