Screening Tools for Depression and Anxiety

PHQ-9 severity: 0–4 = minimal or none; 5–9 = mild depression; 10–14 = moderate; 15–19 = moderately severe; 20–27 = severe. A score ≥10 has 88% sensitivity and 88% specificity for major depressive disorder (Kroenke et al., JAMA 2001). Management guidance: 5–9 = watchful waiting, follow-up in 1 month; 10–14 = antidepressant or therapy referral; 15–19 = antidepressant + therapy; 20–27 = urgent antidepressant initiation + therapy + possible psychiatric referral. Always assess question 9 (suicidality) independently regardless of total score.

GAD-7 severity: 0–4 = minimal; 5–9 = mild; 10–14 = moderate; 15–21 = severe anxiety. A score ≥10 has 89% sensitivity and 82% specificity for generalized anxiety disorder (Spitzer et al., JAMA Internal Medicine 2006). The GAD-7 also detects panic disorder (sensitivity 74%), social anxiety (72%), and PTSD (66%) at a threshold of ≥10. Management: 5–9 = psychoeducation and monitoring; 10+ = CBT referral and/or SSRI/SNRI initiation; 15+ = consider urgent mental health referral. Reassess at 4–8 weeks with treatment.

The PHQ-2 is a 2-item ultra-brief screen asking about depressed mood and anhedonia over the past 2 weeks (scores 0–6). A PHQ-2 score ≥3 has 83% sensitivity and 90% specificity for major depression — it is used as a first-stage screen before administering the full PHQ-9. If PHQ-2 is negative (score 0–2) in a low-risk patient, major depression is unlikely and full PHQ-9 may not be needed. A positive PHQ-2 (≥3) should always trigger the full PHQ-9 for severity classification and treatment planning. USPSTF recommends routine PHQ-2 or equivalent screening for all adults.

The Edinburgh Postnatal Depression Scale is a 10-item self-report tool validated for detecting perinatal depression during pregnancy and in the postpartum period (up to 1 year). Score ≥10 indicates possible depression; ≥13 indicates likely major depressive disorder. Question 10 (self-harm thoughts) requires immediate clinical follow-up regardless of total score. NICE guidelines recommend screening at the antenatal booking appointment and again at 4–6 weeks postpartum. ACOG recommends at least one EPDS or equivalent screening during the perinatal period. A positive screen requires clinical assessment — it is not diagnostic.

The Hospital Anxiety and Depression Scale (HADS) contains 14 items — 7 for anxiety and 7 for depression — each scored 0–3, giving separate anxiety (HADS-A) and depression (HADS-D) subscales of 0–21. Score interpretation for each subscale: 0–7 = normal; 8–10 = borderline; 11–21 = definite case. HADS was specifically designed to minimize the effect of physical illness on psychological scoring, making it particularly useful in medically ill patients and oncology settings where somatic symptoms of depression (fatigue, sleep disturbance) may reflect physical disease rather than mood disorder.

Psychiatric referral is indicated for: PHQ-9 ≥20 (severe depression); active suicidal ideation with plan or intent; psychotic features (hallucinations, delusions); bipolar disorder (use MDQ to screen); two failed adequate antidepressant trials (treatment-resistant depression); comorbid substance use disorder; eating disorder requiring specialist care; or patient/clinician request. In primary care, most mild-to-moderate depression (PHQ-9 10–19) can be managed with SSRIs and brief structured psychotherapy (CBT). Collaborative care models improve outcomes in primary care depression management.