The U.S. Preventive Services Task Force recommends depression screening for adults in primary care when systems support diagnosis, treatment, and follow-up. Depression can still go unrecognized when clinics lack a consistent workflow.
The PHQ-9 and PHQ-2 are validated, brief, and free. The challenge is fitting them into visits already packed with competing demands.
Why universal screening matters
Many adults don't volunteer depression symptoms. Screening can flag concerns that symptom-based conversations miss. The USPSTF recommendation includes pregnant and postpartum adults when systems exist for appropriate follow-up.
Depression screening also ties to quality metrics: HEDIS measures, Medicare quality programs, and value-based contracts. Non-screening has reimbursement implications beyond clinical concerns.
Tiered screening: PHQ-2 first, PHQ-9 if positive
Universal full screening isn't practical. Every patient can't complete a full PHQ-9 at every visit. The tiered approach balances coverage with efficiency.
Step 1: PHQ-2 for everyone. The PHQ-2 asks about diminished interest and depressed mood over the past two weeks, scored 0-3 each. At a cutoff of 3, sensitivity is 83% and specificity is 92%. A cutoff of 2 raises sensitivity to 91% and lowers specificity to 78% (Kroenke et al., 2003). Choose the cutoff in the practice protocol before screening begins.
Step 2: PHQ-9 for positive PHQ-2. The PHQ-9 adds a structured estimate of symptom severity and includes an item about thoughts of death or self-harm. It does not confirm depression.
Workflow implementation
Who screens? Options include medical assistants during rooming (most reliable), tablets at check-in, paper in the waiting room, or electronic pre-visit via email or text (lower completion without prompting). Integrating screening with vital signs works better than treating it as a separate task.
When to screen? Annual wellness visits and new-patient visits are common opportunities. Set the interval from the current guideline, measure specification, patient context, and practice protocol.
Step-by-step:
- EHR flags patients due for screening
- During rooming, MA asks PHQ-2 questions or confirms patient self-completed
- If score >=3 (or >=2 per your protocol), administer PHQ-9
- Results documented in EHR before provider enters
- Provider reviews results; positive screens flagged for attention
- Clinical assessment and response during visit
Sample script for staff: "I'm going to ask you two quick questions about your mood that we ask all our patients." If positive: "Based on those answers, I'd like you to complete a few more questions so we can better understand how you're doing."
Responding to positive screens
A positive screen isn't a diagnosis. It's the start of clinical assessment, and the total does not select a treatment or referral.
PHQ-9 scores 5-9 (mild): Record the mild symptom band. Review the item pattern, functioning, medical context, substance use, and life circumstances.
PHQ-9 scores 10-14 (moderate): Record the moderate symptom band. Use the interview to assess duration, impairment, differential diagnoses, and the patient's account.
PHQ-9 scores 15+ (moderately severe to severe): Record the applicable symptom band and complete the clinical assessment. The total alone cannot determine urgency, medication, psychotherapy, or referral.
Item 9 response: Any score >0 on item 9 requires direct assessment regardless of total score. Ask about suicidal thoughts, assess specificity (passive thoughts vs. active plans), evaluate intent and access to means, and implement appropriate safety measures.
When to refer vs. manage in primary care
Refer to behavioral health: Patient prefers therapy, moderate-to-severe depression not responding to initial treatment, complex or comorbid presentation, suicidal ideation requiring specialty assessment.
Manage in primary care: Mild to moderate depression with straightforward presentation, patient preference, good response to initial treatment. Collaborative care models blur this distinction, since integrated behavioral health enables shared management.
Follow-up and measurement-based care
For patients being monitored, choose a reassessment interval that fits the PHQ-9 recall period, the care plan, and local protocol. Compare the same questionnaire over time, and review the answers alongside function and the clinical interview.
- Record the raw total and item-level answers.
- Describe the direction and size of a score change without assigning a cause.
- Do not use a total alone to declare response or remission.
If the score pattern and clinical picture do not align: Reassess the diagnosis, adherence, comorbid conditions, functioning, and treatment context. Base any change in care on that fuller review.
When patients decline treatment: Document that you discussed results and options, note their reasons if provided, and offer rescreening at a future visit. Respect autonomy while keeping the door open.
Common implementation challenges
"We don't have time." Pre-visit electronic screening uses no visit time. PHQ-2 takes 30 seconds during rooming. Positive screens justify additional time.
"Too many false positives." The PHQ-2 is sensitive by design. It's a screener. The PHQ-9 adds specificity. Clinical assessment determines need, not screening alone. Brief conversations after false positives have low cost.
"Patients resist the questions." Most accept screening when framed as routine: "we ask everyone." Some discomfort is acceptable for important health information.
"I'm not trained to treat depression." Mild to moderate depression is manageable in primary care with evidence-based treatments. Training is available and worthwhile. Referral resources exist for complex cases.
Measuring success
Process measures: Screening rate, timeliness of follow-up for positive screens, and documentation completeness.
Outcome measures: Detection rate, treatment initiation rate for positive screens, PHQ-9 score improvement over time, referral completion rates.
Review metrics regularly: What's our current screening rate? Are positive screens getting appropriate follow-up? Where are patients falling through the cracks?
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Depression screening is easier to sustain when it is built into workflow rather than added on top. Automate the prompts, standardize the process, and track completion. The PHQ-2 provides a brief first step, and the PHQ-9 adds detail for clinical review. Diagnosis and treatment decisions remain with the clinician.