Psychiatry

PHQ-9 Calculator

The Patient Health Questionnaire-9 is a validated tool for screening and tracking the severity of depression.

1. Little interest or pleasure in doing things

2. Feeling down, depressed, or hopeless

3. Trouble falling/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

7. Trouble concentrating

8. Moving/speaking slowly, or being fidgety/restless

9. Thoughts that you would be better off dead, or of hurting yourself

What is the PHQ-9?

The PHQ-9 is a 9-item self-report tool based on DSM diagnostic criteria for major depressive disorder, developed by Kroenke, Spitzer, and Williams and validated for both screening and tracking treatment response over time. Each item is scored 0-3 based on frequency over the past two weeks.

Interpretation

Score	Severity
0-4	Minimal or none
5-9	Mild
10-14	Moderate
15-19	Moderately severe
20-27	Severe

Item 9 always matters

Item 9 asks about thoughts of self-harm. A positive response to this item should always prompt a direct, immediate assessment of suicide risk, regardless of the total score — a mild total score does not make a positive item 9 less significant.

References

Kroenke K, Spitzer RL, Williams JB. The PHQ-9: validity of a brief depression severity measure. J Gen Intern Med. 2001.

Frequently Asked Questions

What if item 9 is positive but the total score is low?

Any positive response to item 9 warrants direct assessment of suicide risk, regardless of the total score — it should never be dismissed just because the overall score is mild.

Does PHQ-9 diagnose depression?

No — it's a screening and severity-tracking tool. Diagnosis requires full clinical assessment against diagnostic criteria.

How often is PHQ-9 repeated?

It's commonly repeated at follow-up visits to track treatment response over time, using the same two-week recall window each time.