PHQ-2 Score (Patient Health Questionnaire-2): 2-Item Depression Screening, Cutoff ≥3 Psychometrics, PHQ-9 Branching, and LOINC 55758-7

Short answer: The Patient Health Questionnaire-2 (PHQ-2) is a validated, ultra-brief depression screening instrument developed by Kurt Kroenke, Robert L. Spitzer, and Janet B.W. Williams (2003) that consists of the first two items of the PHQ-9. It measures the frequency of depressed mood and anhedonia over the past two weeks on a 0–3 Likert scale per item, yielding a total PHQ-2 score from 0 to 6. In the foundational validation study across 6,000 primary care and obstetrics-gynecology patients, a PHQ-2 score of 3 or greater (≥ 3) established the optimal screening threshold, demonstrating 82.9% sensitivity and 90.0% specificity for Major Depressive Disorder. Because the PHQ-2 is a first-stage screener rather than a diagnostic instrument, a positive screen (≥ 3) triggers administration of the full 9-item PHQ-9 and a clinical interview. In interoperable health IT systems, the PHQ-2 total score is standardized under LOINC code 55758-7.

What is the PHQ-2 score and how are the two items scored?

Derived directly from the Primary Care Evaluation of Mental Disorders (PRIME-MD) and the PHQ-9, the PHQ-2 asks respondents: “Over the last 2 weeks, how often have you been bothered by the following problems?”

1. Item 1 (Anhedonia — LOINC 44250-9): “Little interest or pleasure in doing things”
2. Item 2 (Depressed Mood — LOINC 44255-8): “Feeling down, depressed, or hopeless”

Each item is scored using four standardized frequency anchors:

• 0 points: Not at all (LOINC answer code LA6568-5)
• 1 point: Several days (LOINC answer code LA6569-3)
• 2 points: More than half the days (LOINC answer code LA6570-1)
• 3 points: Nearly every day (LOINC answer code LA6571-9)

Summing the two item scores produces a PHQ-2 total score (LOINC 55758-7) ranging from 0 to 6. The instrument is in the public domain (developed by Drs. Spitzer, Williams, and Kroenke with an educational grant from Pfizer Inc.) and requires no licensing fee for clinical care or clinical research.

Validated cutoff scores: Sensitivity and specificity (Kroenke et al., 2003)

In the landmark 2003 validation study published in Medical Care (6,000 patients across 8 primary care and 7 obstetrics-gynecology clinics, with 580 patients undergoing independent structured interviews by mental health professionals), Kroenke et al. evaluated operating characteristics across every possible PHQ-2 cutoff score from ≥ 1 to ≥ 6:

PHQ-2 Total Score Cutoff	Sensitivity for Major Depressive Disorder (%)	Specificity for Major Depressive Disorder (%)	Positive Likelihood Ratio (MDD)	Sensitivity for Any Depressive Disorder (%)	Specificity for Any Depressive Disorder (%)
≥ 1	97.6%	59.2%	2.4	90.6%	65.4%
≥ 2	92.7%	73.7%	3.5	82.1%	80.4%
≥ 3 (Standard Cutoff)	82.9%	90.0%	8.3	62.3%	95.4%
≥ 4	73.2%	93.3%	10.9	50.9%	97.9%
≥ 5	53.7%	96.8%	16.8	31.1%	98.7%
≥ 6	26.8%	99.4%	44.7	12.3%	99.8%

A cutoff of ≥ 3 provides the optimal trade-off between sensitivity and false-positive burden in routine screening, though some clinical trials or specialty screening protocols use a lower threshold of ≥ 2 when maximizing sensitivity (92.7% for Major Depressive Disorder) is prioritized over specificity.

Two-stage branching to the PHQ-9 in digital patient intake and EHR workflows

Because the PHQ-2 consists of the exact first two questions of the PHQ-9, digital patient intake platforms and EHR patient portals implement a two-stage reflex (conditional branching) workflow:

1. Stage 1 (Universal Pre-Visit Screen): Every patient completing pre-consultation intake answers the two PHQ-2 items (often paired with the 2-item GAD-2 derived from the GAD-7 or somatic screening instruments like the PHQ-15).
2. Negative Screen (PHQ-2 < 3): The questionnaire terminates without presenting the remaining 7 depression items, reducing respondent fatigue while recording a documented negative depression screen.
3. Positive Screen (PHQ-2 ≥ 3): Conditional logic (enableWhen in an HL7 FHIR Questionnaire resource) immediately displays Items 3 through 9 of the PHQ-9 during the same session. Because Items 1 and 2 have already been answered, the system sums all 9 responses to generate the full PHQ-9 severity score (0–27) and flags Item 9 (thoughts of self-harm or being better off dead) for immediate clinical review.

What standards, quality measures, and LOINC codes govern the PHQ-2 score?

In U.S. clinical quality reporting and EHR interoperability, the PHQ-2 is governed by standardized terminology and value sets:

• LOINC Terminology Mapping: The PHQ-2 panel is represented by LOINC 55757-9 (Patient Health Questionnaire 2 item (PHQ-2) [Reported]), with total score code 55758-7 (Patient Health Questionnaire 2 item (PHQ-2) total score [Reported]).
• CMS eCQM CMS2 (MIPS Quality ID 134): Under Preventive Care and Screening: Screening for Depression and Follow-Up Plan, the PHQ-2 is an eligible standardized adult and adolescent depression screening tool. When a PHQ-2 screen is positive per the clinic’s validated threshold, CMS2 requires a documented follow-up plan (such as completion of a full diagnostic assessment/PHQ-9, referral, or pharmacotherapy/psychotherapy intervention) on the date of the encounter.
• USCDI and HL7 FHIR R4 Observation Modeling: Under ONC/ASTP USCDI v3+ Health Status Assessments, EHRs exchange PHQ-2 scores as HL7 FHIR Observation resources with category survey, code http://loinc.org|55758-7, and an integer valueQuantity or valueInteger between 0 and 6.

Frequently asked questions

What is phq-2 score and how is it used in clinical research and healthcare?

The PHQ-2 score is the 0-to-6 sum of the two-item Patient Health Questionnaire-2, which screens for core depressive symptoms (anhedonia and depressed mood) over the prior two weeks. In healthcare and clinical trials, it serves as a rapid first-stage screening gate: patients scoring 3 or higher are routed to complete the full 9-item PHQ-9 or a structured diagnostic evaluation.

What standards or regulatory requirements govern phq-2 score?

In health information technology, the PHQ-2 score is standardized under LOINC code 55758-7 (panel 55757-9) and HL7 FHIR R4 QuestionnaireResponse and Observation profiles. In U.S. value-based care, it satisfies depression screening requirements under CMS electronic clinical quality measure CMS2 (Preventive Care and Screening: Screening for Depression and Follow-Up Plan) when paired with a documented follow-up action for positive screens.

How does phq-2 score integrate with EHR and health informatics workflows?

EHR patient portals and digital intake systems embed the PHQ-2 using conditional branching (enableWhen logic). If a patient’s responses to the first two items sum to 0, 1, or 2, the screen closes as negative; if the sum is 3 to 6, the form automatically expands to collect the remaining seven items of the PHQ-9 before filing both LOINC-coded scores into the EHR flowsheet.

Sources

• Kroenke K, Spitzer RL, Williams JBW (2003) — “The Patient Health Questionnaire-2: Validity of a Two-Item Depression Screener”, Medical Care 41(11):1284–1292
• Regenstrief Institute — LOINC 55758-7: Patient Health Questionnaire 2 item (PHQ-2) total score [Reported]
• Centers for Medicare & Medicaid Services (CMS) — eCQI Resource Center: CMS2 Preventive Care and Screening: Screening for Depression and Follow-Up Plan