- Ask the patient: over the last 2 weeks, how often have you been bothered by each problem?
- For each of the nine items, select the frequency — Not at all (0), Several days (1), More than half the days (2), or Nearly every day (3).
- The total (0–27), the severity band, and the PHQ-2 subtotal update live as you score.
- If item 9 (thoughts of self-harm) scores 1 or more, the result turns red and surfaces a safety alert — regardless of the total.
- Interpret somatic items (sleep, energy, appetite, psychomotor) in the context of uremia, dialysis, and anemia, which overlap with these symptoms.
All scoring runs in your browser; no answers are stored or transmitted. The PHQ-9 is in the public domain.
When to Use
The PHQ-9 is a brief, validated, self-administered instrument that both screens for and grades the severity of depression using the nine DSM criteria for major depressive disorder. Use it to screen adults in primary care and in CKD/dialysis clinics, to establish a baseline severity, and to track response to treatment over time. Depression is common but under-recognized in kidney disease — prevalence estimates run roughly 25–40% in dialysis populations — and is associated with poorer adherence, quality of life, and outcomes, so routine screening is reasonable.
Appropriate population
Adults able to report on their mood over the preceding two weeks. Particularly useful in CKD, dialysis, and transplant clinics for case-finding and for monitoring treatment response. The PHQ-9 (and the CES-D) have been validated in dialysis populations.
What it is not
The PHQ-9 is a screening and severity tool, not a diagnosis. A positive screen requires clinical confirmation of major depressive disorder and exclusion of mimics (e.g. hypothyroidism, anemia, uremia, medication effects, bipolar disorder). Somatic items — sleep, fatigue, appetite, psychomotor change — overlap heavily with CKD and dialysis symptoms and can inflate the score, so interpret them in clinical context.
Pearls & Pitfalls
Item 9 is a hard stop
Any score ≥1 on item 9 (thoughts that you would be better off dead, or of hurting yourself) mandates an immediate suicide-risk assessment, regardless of the total score. A low total does not reassure if item 9 is positive. This calculator forces a red safety alert in that case.
≥10 is the actionable threshold
A total ≥10 has good sensitivity and specificity for major depression and should prompt further assessment and treatment. The PHQ-2 (items 1+2; positive if ≥3) is a useful ultra-brief pre-screen — a positive PHQ-2 should be followed by the full PHQ-9.
Read somatic items in CKD context
Fatigue, poor sleep, appetite change, and psychomotor slowing overlap with uremia, dialysis, and anemia and can elevate the score independent of mood. Weight the affective and cognitive items (interest/pleasure, depressed mood, worthlessness, hopelessness) when the somatic picture is confounded. If antidepressant therapy is indicated, SSRIs are generally preferred in CKD (e.g. sertraline), with dose caution and monitoring for QT prolongation and hyponatremia (SIADH).
Why Use It
Depression in CKD is frequently missed because its somatic features are attributed to kidney disease itself, yet it independently worsens adherence, quality of life, hospitalization, and mortality. A structured, quantitative screen converts a vague clinical impression into a reproducible severity score that can be tracked across visits and used to gauge treatment response. Pairing the PHQ-2 pre-screen with the full PHQ-9 makes routine case-finding feasible in a busy nephrology clinic, and the built-in item-9 safety flag ensures self-harm risk is never overlooked even when the overall score looks mild.
PHQ-9 Depression Severity Calculator — CKD-aware
Over the last 2 weeks, how often has the patient been bothered by any of the following problems? Score each item; the total, severity band, PHQ-2 subtotal, and item-9 safety flag compute live.
⚕ PHQ-9 total = sum of the 9 items (0–3 each), range 0–27. Bands: 0–4 none–minimal · 5–9 mild · 10–14 moderate · 15–19 moderately severe · 20–27 severe. ≥10 is clinically significant for major depression. PHQ-2 = items 1+2; positive if ≥3. Item 9 ≥1 mandates an immediate suicide-risk assessment regardless of the total. Screening/severity tool, not a diagnosis — confirm clinically; somatic items overlap with CKD symptoms. Source: Kroenke K, Spitzer RL, Williams JBW. J Gen Intern Med. 2001;16(9):606–613. PHQ-9 is in the public domain.
Next Steps
Use the score to support — not replace — clinical judgment.
- Item 9 positive (≥1): perform an urgent suicide-risk assessment now, ensure safety, and escalate to mental-health/crisis services as indicated — regardless of the total score.
- Total ≥10: consider major depressive disorder; pursue further assessment and treatment (psychotherapy and/or pharmacotherapy) after confirming the diagnosis and excluding mimics.
- If pharmacotherapy is chosen in CKD: SSRIs are generally preferred (e.g. sertraline) with dose caution; monitor for QT prolongation and hyponatremia (SIADH).
- Total 5–9: mild symptoms — consider watchful waiting with repeat scoring, supportive measures, and re-assessment.
- Interpret somatic items (sleep, energy, appetite, psychomotor) in the context of uremia, dialysis, and anemia; trend serial PHQ-9 scores to gauge treatment response.
Evidence & References
Scoring
| Quantity | Definition |
|---|---|
| PHQ-9 total | Sum of all 9 items, each scored 0 (Not at all) to 3 (Nearly every day); range 0–27 |
| PHQ-2 subtotal | Items 1 + 2 only; positive if ≥3 — prompts the full PHQ-9 |
| Item-9 flag | Any score ≥1 on item 9 ⇒ immediate suicide-risk assessment, regardless of total |
| Clinically significant | Total ≥10 (good sensitivity/specificity for major depression) |
Severity bands
| PHQ-9 total | Severity | Suggested action |
|---|---|---|
| 0–4 | None–minimal | No action typically needed |
| 5–9 | Mild | Watchful waiting; repeat PHQ-9 at follow-up |
| 10–14 | Moderate | Treatment plan: psychotherapy and/or pharmacotherapy |
| 15–19 | Moderately severe | Active treatment with pharmacotherapy and/or psychotherapy |
| 20–27 | Severe | Pharmacotherapy and expedited specialist referral |
In CKD and dialysis populations the somatic items (sleep, fatigue, appetite, psychomotor change) overlap with uremia, anemia, and dialysis, and may elevate the score independent of mood — weight the affective and cognitive items and confirm clinically.
Evidence & References
The PHQ-9 is the depression module of the Patient Health Questionnaire (PRIME-MD), validated by Kroenke and colleagues in 2001 as a brief, reliable measure of depression severity that maps directly onto the DSM criteria. A total ≥10 has good sensitivity and specificity for major depression. Depression is highly prevalent in dialysis populations (≈25–40%) and is under-recognized; both the PHQ-9 and the CES-D have been validated in this setting (e.g. Hedayati and colleagues). The PHQ-9 is in the public domain.
- Kroenke K, Spitzer RL, Williams JBW. The PHQ-9: Validity of a Brief Depression Severity Measure. J Gen Intern Med. 2001;16(9):606–613.
- Hedayati SS, Bosworth HB, Kuchibhatla M, et al. The predictive value of self-report scales compared with physician diagnosis of depression in hemodialysis patients. Kidney Int. 2006;69(9):1662–1668.
- Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney Int. 2024;105(4S):S117–S314.
