PHQ-9 (Patient Health Questionnaire-9): Items, Scoring, and Cut-Offs

If you have ever opened a thesis dataset and wondered what the PHQ-9 numbers actually mean, this guide is for you. PHQ-9 scoring interpretation is simpler than most students expect: nine questions, four answer options each, and one total score from 0 to 27 — plus five severity bands that tell you, at a glance, how serious the depressive symptoms look. This post walks through the nine items, the exact scoring rules, the cut-off scores at 5, 10, 15 and 20, and the evidence behind the scale, so you can use it confidently in your own research.

What Does the PHQ-9 Measure?

The Patient Health Questionnaire-9 (PHQ-9) is a nine-item self-report questionnaire that screens for depression and measures the severity of depressive symptoms. It was developed by Drs. Kurt Kroenke, Robert L. Spitzer and Janet B. W. Williams and published in the Journal of General Internal Medicine in 2001. It takes most people about three minutes to complete, which is a large part of why it has become one of the most widely used depression measures in both clinical practice and student research.

Each of the nine items mirrors one of the nine diagnostic criteria for major depressive disorder. That design is deliberate: the PHQ-9 was built from the PRIME-MD diagnostic interview, so a high score does not only mean “more symptoms” — it means more of the specific symptoms that define depression. Researchers use it to screen participants, to describe a sample’s symptom severity, and to track whether symptoms improve over the course of a study or an intervention.

The 9 Items of the PHQ-9

Every item begins with the same instruction: “Over the last 2 weeks, how often have you been bothered by any of the following problems?” The nine items are:

1. Little interest or pleasure in doing things
2. Feeling down, depressed, or hopeless
3. Trouble falling or staying asleep, or sleeping too much
4. Feeling tired or having little energy
5. Poor appetite or overeating
6. Feeling bad about yourself — or that you are a failure or have let yourself or your family down
7. Trouble concentrating on things, such as reading the newspaper or watching television
8. Moving or speaking so slowly that other people could have noticed — or the opposite, being so fidgety or restless that you have been moving around a lot more than usual
9. Thoughts that you would be better off dead or of hurting yourself in some way

Notice the balance: items 1 and 2 cover the two core symptoms of depression (low mood and loss of interest), items 3 to 5 and 7 to 8 cover the physical and cognitive symptoms, and item 9 covers suicidal thoughts. That last item is the reason the PHQ-9 is never just a number — more on that below.

Response Format: The Same Four Options for Every Item

Every item uses the identical four-point frequency scale:

The two-week time frame matters. It matches the duration criterion for a depressive episode, so a participant is reporting on a sustained pattern, not a single bad day. When you administer the scale, keep that window in your instructions — and if you are adapting it for a study, do not change the wording of the time frame without noting it in your methods section, because the published cut-offs were validated with this exact version.

How to Score the PHQ-9

Scoring is a simple sum. Add the nine item scores together and you get a total between 0 and 27. There are no reverse-scored items, no weighting and no subscales to calculate — every item counts equally, and a higher total always means more frequent symptoms. This simplicity was a design goal: the scale was built so that a busy clinic could score it in seconds, and the same simplicity makes it easy to score correctly in a thesis dataset.

Worked Example

Imagine a participant, Sara, who completes the PHQ-9 before starting a study on student wellbeing. Her answers are: little interest 2, feeling down 2, sleep problems 3, tiredness 2, appetite 1, feeling bad about herself 2, concentration 1, psychomotor changes 0, thoughts of self-harm 0. Add them up: 2 + 2 + 3 + 2 + 1 + 2 + 1 + 0 + 0 = 13. Sara’s total score is 13, which falls in the moderate band (10–14). A researcher would report that score, describe it as moderate symptom severity, and — because it crosses the screening threshold of 10 — would note that a clinical follow-up is indicated.

PHQ-9 Cut-Off Scores and Severity Bands

The published cut-points divide the 0–27 range into five bands (Kroenke, Spitzer & Williams, 2001):

Treat these bands as conventions for interpretation, not walls in reality. A score of 9 and a score of 10 describe very similar people; the cut-point exists because researchers and clinicians need a consistent decision rule, not because symptoms change overnight at the boundary. In a thesis, report the exact total score alongside the band — never the band alone.

Why the Cut-Off of 10 Matters Most

Ten is the most important number on the scale. In the original validation study, a score of 10 or higher was the threshold that best identified people likely to meet criteria for major depression. Against an independent mental health professional’s structured interview, in a subsample of 580 patients drawn from the 6,000-patient validation sample, a cut-off of 10 gave 88% sensitivity and 88% specificity. Those are unusually balanced numbers — most screening tools trade one for the other, and the PHQ-9 at 10 does not. That is why 10 is the standard screening threshold in research: in a thesis, the percentage of participants scoring 10 or above is the figure most readers will look for first.

Item 9: The Question That Changes Everything

Item 9 asks about thoughts of being better off dead or of hurting yourself. It is scored 0–3 like every other item, but it carries a different weight in practice: any answer above 0 — even a 1, “several days” — calls for a prompt safety assessment by a clinician, whatever the total score. A participant can score 4 overall and still need an immediate conversation if that 4 came from item 9. If you are using the PHQ-9 in your own study, plan for this before you collect a single response: decide who will follow up on positive item-9 answers, how quickly, and what support information you will give participants. Your ethics approval will almost certainly require it.

The PHQ-2: The Two-Item Short Form

The first two items — little interest and feeling down — can be used on their own as the PHQ-2, a very brief screen. The two items are scored the same way, giving a total from 0 to 6, and a score of 3 or more is the usual trigger to complete the full nine items. The PHQ-2 is handy when questionnaire space is tight, but it cannot grade severity, so for a thesis that needs a depression severity score, use the full PHQ-9.

The Extra Question That Is Not Scored

After the nine items, the official form asks one more question: how difficult the problems have made it to do work, take care of things at home, or get along with other people. This functional-impairment question adds zero points to the total — it is not part of the 0–27 score at all. It is still worth collecting, because it tells you whether symptoms are actually interfering with daily life, which is part of what makes a score clinically meaningful. Just do not add it to the total, or your scores will not be comparable with any published cut-off.

Reliability and Validity Evidence

The psychometric evidence for the PHQ-9 comes from the original validation by Kroenke, Spitzer and Williams (2001), based on 6,000 patients across 8 primary care clinics and 7 obstetrics-gynaecology clinics:

• Internal consistency: Cronbach’s alpha was 0.89 in the primary care sample and 0.86 in the obstetrics-gynaecology sample — well above the usual 0.70 threshold for a research instrument.
• Test-retest reliability: the correlation between the PHQ-9 completed in the clinic and the same items administered by telephone within 48 hours was 0.84, with nearly identical mean scores (5.08 vs 5.03).
• Criterion validity: a score of 10 or above identified major depression with 88% sensitivity and 88% specificity against an independent mental health professional’s interview.
• Construct validity: scores showed strong associations with functional status, disability days and symptom-related difficulty, and correlated 0.73 with the SF-20 mental health scale.
• Cross-cultural use: the scale has been translated into many languages and validated in diverse populations, which is why it appears so often in international student research.

One practical note for your methods section: always report the Cronbach’s alpha you obtained in your own sample, not just the published 0.89. Reliability is a property of the scores in your study, not of the scale in general, and examiners notice when it is missing.

Using the PHQ-9 in Your Research

A few practical rules make the difference between a clean methods section and an examiner’s question. First, the scale is free to use for clinical and research purposes — no permission or fee is required — and the official form and translations are available from the PHQ screeners website (phqscreeners.com). Second, report the total score, the severity band and the proportion of participants at or above 10; that combination lets any reader compare your sample with published norms. Third, if you measure change over time, a drop of 5 points or more is widely treated as a clinically meaningful improvement for an individual, so report mean change and the proportion improving by 5 or more. And finally, never forget the boundary of the instrument: the PHQ-9 is a screening tool. It identifies people who probably have depression and grades their symptoms — it does not diagnose depression. A diagnosis needs a clinical interview, and your thesis should say so plainly.

Common Mistakes to Avoid

1. Treating a score of 10 or above as a diagnosis. It is a screening result. Write “probable depression” or “screened positive”, never “diagnosed with depression”.
2. Ignoring item 9. A low total score does not cancel out a positive answer on thoughts of self-harm.
3. Reverse-scoring items. There are none. Every item is scored 0–3 in the same direction.
4. Adding the difficulty question to the total. It is unscored; adding it inflates the score and breaks comparability with published cut-offs.
5. Reporting only the severity band. Always give the exact total score and, for the sample, the mean and standard deviation.
6. Changing the two-week window. If you must adapt it, say so in your methods and do not apply the standard cut-offs as if nothing changed.

How to Cite the PHQ-9 (APA 7th)

When you use the scale, cite the original validation study in your reference list:

Kroenke, K., Spitzer, R. L., & Williams, J. B. W. (2001). The PHQ-9: Validity of a brief depression severity measure. Journal of General Internal Medicine, 16(9), 606–613. https://doi.org/10.1046/j.1525-1497.2001.016009606.x

In text, write: “Depressive symptoms were measured with the Patient Health Questionnaire-9 (PHQ-9; Kroenke et al., 2001), a nine-item self-report scale scored from 0 to 27, with higher scores indicating more severe symptoms.”

Frequently Asked Questions

What PHQ-9 score indicates depression?
A score of 10 or above is the standard screening threshold for likely major depression. In the original validation it identified major depression with 88% sensitivity and 88% specificity. Scores of 5–9 suggest mild symptoms worth monitoring, and scores below 5 suggest minimal symptoms.

Is the PHQ-9 free to use?
Yes. The PHQ-9 is free to use for clinical and research purposes with no permission or fee required. The official form and its translations are available from the PHQ screeners website.

Does the PHQ-9 diagnose depression?
No. It is a screening and severity measure, not a diagnostic tool. It tells you how likely depression is and how severe the symptoms are; only a clinical interview can make a diagnosis.

What is the difference between the PHQ-9 and the PHQ-2?
The PHQ-2 is just the first two items of the PHQ-9, scored 0–6, used as a quick screen. A score of 3 or more on the PHQ-2 means the full PHQ-9 should be completed. The PHQ-2 cannot grade severity.

Can I use the PHQ-9 with adolescents?
The PHQ-9 was developed and validated for adults. A modified version, the PHQ-9A, is used with adolescents, and the PHQ-9 has been validated in adolescent samples in some settings — check the validation literature for your specific population before using the adult version with teenagers.

Key Takeaways

• The PHQ-9 has 9 items, each scored 0–3 over the past two weeks, for a total of 0–27. There are no reverse-scored items.
• Severity bands are 0–4 minimal, 5–9 mild, 10–14 moderate, 15–19 moderately severe and 20–27 severe.
• A score of 10 or above is the standard screening threshold (88% sensitivity, 88% specificity).
• Any score above 0 on item 9 needs a prompt safety check, regardless of the total.
• The scale is free to use, well validated (alpha 0.89, test-retest 0.84), and cited as Kroenke, Spitzer & Williams (2001).
• It screens and grades symptoms — it does not diagnose depression.

Used carefully, the PHQ-9 gives a thesis a depression measure that is brief, free, widely recognised and easy to defend in a viva. Pair it with a clear methods description and your own sample’s reliability figure, and it will serve your study well.