Depression Screening: What the PHQ-9 Can and Cannot Tell

Depression screening means a short questionnaire, usually the PHQ-9 or its two question version, that a doctor uses to decide who needs a fuller assessment. It is not a diagnosis. The USPSTF says every positive result should lead to more assessment, and NICE says assessment must not rely simply on a symptom count.

On this page: a table of six screening questionnaires with the paper or guideline behind each one, the PHQ-9’s accuracy figures from 580 to 6,725 people, the study that found a score of 10 or more roughly doubles the apparent depression rate, and what people who filled one in report.

What is depression screening, and what is it not?

Screening is a sieve, not a verdict. It asks a lot of people a few questions so that the ones who may need a proper conversation get one. The US Preventive Services Task Force made its position plain in its final statement of 20 June 2023: it “recommends screening for depression in the adult population”, a grade B recommendation that covers pregnant and postpartum people and adults over 65 too. In the same breath it says “All positive screening results should lead to additional assessments to confirm the diagnosis.”

The task force drew a line in a second place as well. On screening for suicide risk in adults who show no signs of it, it found the evidence “insufficient to assess the balance of benefits and harms”. That is a statement about routine screening, not about asking someone who is struggling. NICE guideline NG222 tells clinicians to “always ask people with depression directly about suicidal ideation and intent” in recommendation 1.2.8.

NICE, which writes the guidance for England, takes a gentler route than blanket screening. Its recommendation 1.2.1 says to “be alert to possible depression”, especially in people with a past history of it or a long term physical illness, and to consider asking two questions about the last month: have they often been bothered by “feeling down, depressed or hopeless”, and by “having little interest or pleasure in doing things”. A yes to either leads to an assessment, not to a label.

Which questionnaires are used, and who made them?

Most of the names that turn up on a clinic clipboard come from a short list of published scales. The table below is compiled from the original papers and the two guidelines, with the source linked in the first column of every row. It describes what each one was built for; it is not a way to pick one for yourself.

Questionnaire	Questions	What it was built to screen for	Who developed it	First tested on
PHQ-9	9	Depression, and how severe it is	Kroenke, Spitzer and Williams, Journal of General Internal Medicine, 2001	6,000 patients in 8 primary care and 7 obstetrics clinics
PHQ-2	2	Low mood and loss of interest over the past 2 weeks	Kroenke, Spitzer and Williams, Medical Care, 2003	The same 6,000 patients
NICE two questions	2	Feeling down and little interest or pleasure “during the last month”	NICE guideline NG222, recommendation 1.2.1	A guideline, not a scored scale
GAD-7	7	Generalised anxiety, not depression	Spitzer, Kroenke, Williams and Löwe, Archives of Internal Medicine, 2006	2,740 adults in 15 US primary care clinics
EPDS	10	Depression after birth, and in pregnancy in later use	Cox, Holden and Sagovsky, British Journal of Psychiatry, 1987	Validated on 84 mothers
GDS	30	Depression in older adults	Yesavage and colleagues, Journal of Psychiatric Research, 1982	New groups of older adults, after 30 questions were picked from 100

Two things stand out. The PHQ family is the workhorse: the PHQ-9 scores each of nine symptoms from 0, “not at all”, to 3, “nearly every day”, and the USPSTF names “the Patient Health Questionnaire (PHQ) in various forms” for adults, the GDS for older adults and the EPDS for pregnancy and after birth. And the GAD-7 is on the list only because it travels with the PHQ-9 so often. It screens for anxiety, which has its own page here on the signs of anxiety.

How accurate is the PHQ-9 at spotting depression?

Good, as screening tools go, and the numbers are worth reading slowly. In the original 2001 study, 580 people also had an interview with a mental health professional. Against that interview, a PHQ-9 score of 10 or more picked up 88% of people with major depression (the sensitivity) and correctly cleared 88% of people without it (the specificity). A much larger 2019 BMJ analysis pooled the raw data of 58 studies and 17,357 people; in the 29 studies that used a clinician style interview it found almost the same, 88% and 85%.

Questionnaire and cut point	Source	Sample	Sensitivity	Specificity
PHQ-9 at 10 or more, original study	Kroenke 2001	580 people interviewed	88%	88%
PHQ-9 at 10 or more, pooled	Levis 2019, BMJ	29 studies, 6,725 people	88%	85%
PHQ-2 at 3 or more	Kroenke 2003	580 people interviewed	83%	92%
GAD-7 at its best cut point	Spitzer 2006	965 people interviewed	89%	82%

Now the catch, which almost no quiz page mentions. Specificity of 85% sounds high, but in a waiting room where most people are not depressed, 15% of a large group is a lot of false alarms. A 2020 analysis by the same group of 44 studies and 9,242 people found that counting everyone at 10 or more gave a depression rate of 24.6%, when the structured interview found 12.1%: about double. Taken study by study, the average was 2.5 times too high. Its authors open with a sentence every quiz should print at the top: “Depression symptom questionnaires are not for diagnostic classification.” These are figures about groups of patients in studies. They say nothing about any one person who fills in the form.

Why is a score from a website not a diagnosis?

Because a website cannot do the part that matters. NICE recommendation 1.2.6 asks for an assessment that “does not rely simply on a symptom count” and also weighs severity, previous history, how long it has lasted and how much it affects daily life. A form on a screen can do none of that. It cannot ask why someone is sleeping badly, and it cannot weigh the things NICE recommendation 1.2.7 lists, from bereavement and physical illness to medicines, alcohol, debt and loneliness.

Even the cut points are not fixed. The 2001 paper set PHQ-9 scores of 5, 10, 15 and 20 as mild, moderate, moderately severe and severe; NICE used 16 as its line between “less severe” and “more severe” depression in its own guideline. Two respected bodies, two different lines, which is a decent hint that a number needs a person to read it.

Some ranking pages promise more than the research does. One therapy platform’s screening page, updated 13 March 2024, says the results can help you “decide whether your symptoms reflect normal levels of sadness”, and further down that they “cannot give you a diagnosis”. The two sit uneasily together. Sorting ordinary sadness from depression is the clinical judgement NICE describes, and the 2020 prevalence study shows what happens when a cut point is asked to make it alone. This site’s page on what brain training apps can and cannot claim runs into the same habit from the other direction: a score dressed up as a finding.

What do people who have filled one in report?

These accounts are testimony, not evidence, and none is a finding about any person or treatment. Four sources were read: two pages of the Oxford health experiences archive and two Reddit threads from 2026, with about 45 accounts and comments between them; these are the ones that spoke to questionnaires.

On the archive’s young people’s diagnosis page (updated July 2025), Dan, 22, filled in a short form at both a counselling service and his GP. Comparing his answers with how he would have answered a year earlier helped him see things had changed, and he found it “kind of good to sort of have that form”. Edward, 18, saw it the other way: with no definitive test, he felt diagnosis stays “a bit subjective”, and thought that could put some people off talking to a GP.

In a January 2026 r/therapists thread, a trainee asked how to give the PHQ-9 without sounding robotic. Of 33 comments, most from people describing themselves as clinicians, the common advice was to let the person fill it in as written and then talk about the answers. One gave an example of why: someone may tick poor appetite because of fasting or a medicine, which only a follow up question reveals. They disagreed on whether reading it aloud spoils it.

And in a September 2026 r/depression thread, someone reported scoring 94 on one website’s test and 26 on another, and asked which to believe. One reply named a different questionnaire as “the official” test. None of the bodies above names any single official test. The accounts agree with the guidance on one point: the form is a way in, and the conversation after it is where the answer is.

What happens after a screening questionnaire?

In the guidance, a conversation. NICE recommendations 1.2.2 and 1.2.3 say that after a yes to either question, a practitioner who is trained reviews the person’s mental state and their “functional, interpersonal and social difficulties”, and one who is not refers them to someone who is. Recommendation 1.2.4 allows a “validated measure” such as the PHQ-9 “to inform and evaluate treatment”, which is why the same form may reappear at later visits. Who does what next is set out in this site’s page on counsellors, psychologists and psychiatrists.

The NHS page on what to ask your doctor suggests writing down “details of your symptoms, including when they started and what makes them better or worse”, your “2 or 3 most important questions”, and every medicine, including vitamins and supplements. The signs the public bodies list are quoted side by side on this site’s signs of depression page.

If concentration or memory is part of what you want to describe, a dated note of how it moved over a few weeks can help, and the free five minute check-in on this site keeps one. It is not a depression test, it measures nothing about mood, and its score compares only with your own earlier days. Hand it over and let the professional read it.

Where is help if it is needed now?

In India, Tele-MANAS answers on 14416 or 1800 891 4416, free and at any hour; the numbers were confirmed in 2026 coverage, and the Tele-MANAS site is the service’s own page. In the United States, the 988 Suicide and Crisis Lifeline can be called or texted on 988. In the UK, the NHS lists Samaritans on 116 123, the Shout text line (text SHOUT to 85258) and NHS 111, and says to call 999 or go to A&E if you have seriously harmed yourself or feel you may be about to.

If your mood, sleep, memory or thinking has changed in a way that worries you or the people close to you, talk to your doctor. No questionnaire on a website, and no score from any app, replaces that conversation.

Mufy Pachorawala, who writes these pages and runs the Awareness Score app, is not a doctor or a psychologist, which is why every questionnaire here is linked to the paper that introduced it and every rule to the body that wrote it.

Frequently asked questions

---

General information from published research and public health bodies, checked on 7 November 2026. It is not medical advice, and the Awareness Score app is not a medical test. If your memory or thinking has changed noticeably, or worries you or the people close to you, talk to your doctor.