Introduction and Context
Healthy aging—defined by the World Health Organization as the process of developing and maintaining the functional ability that enables well‑being in older age—has become a global public health priority as populations age rapidly (WHO, 2015). In primary care and community health settings, a wide array of health‑promotion and prevention programs aim to preserve function, prevent frailty, and maintain quality of life. Yet the research and evaluation landscape is fragmented: trials and programs use heterogeneous outcomes, impeding pooled evidence, meta‑analysis, and evidence‑based scaling of effective interventions.
In 2025 Jang and colleagues published a focused expert consensus in Integrative Medicine Research describing the development of a Core Outcome Set (COS) for healthy aging interventions delivered in primary care settings in South Korea (Jang et al., 2025). The COS—built following COS‑STAD guidance and a structured Delphi process—identifies 12 outcomes that should, at minimum, be collected and reported in trials and program evaluations. This article summarizes the COS development, the selected outcomes, practical recommendations for implementation, and expert commentary on utility, limitations, and next steps.
Key documents and frameworks informing this work include the WHO’s aging reports and the COMET/COS guidance on developing Core Outcome Sets (WHO 2015; Williamson et al., 2017). The new COS addresses a critical gap: standardized outcome measurement for health‑promotion interventions targeting functional ability, well‑being, and physiologic risk factors in older adults in primary care.
New Guideline Highlights
Major takeaways from the COS work (Jang et al., 2025):
– A compact COS of 12 outcomes suitable for primary care and community health programs. These are a mix of patient‑reported outcomes (PROs), functional measures, and common clinical biomarkers.
– The COS was derived from a literature review of 26 studies and refined through two rounds of a modified Delphi survey with 16 multidisciplinary experts followed by project management group (PMG) review and consensus.
– The COS is intended to be pragmatic and feasible in routine primary care settings while covering domains of quality of life, mental health, function, physiologic risk, and aging‑specific constructs.
The 12 core outcomes selected are:
1. EQ‑5D (health‑related quality of life)
2. Geriatric Depression Scale (GDS)
3. Instrumental Activities of Daily Living (IADL)
4. Body weight
5. Blood pressure
6. Blood glucose
7. Blood lipids
8. Liver function tests
9. Kidney function tests
10. Korean Frailty Index (KFI)
11. Self‑rated health
12. Kidney‑Deficiency Score (a traditional medicine symptom score used in Korean integrative settings)
The COS emphasizes routinely measurable endpoints that primary care teams can collect with modest additional burden.
Why the COS Was Issued
The authors and participating experts identified several drivers for issuing the COS:
– Heterogeneity of outcomes in trials and programs evaluating healthy aging interventions, limiting comparability and meta‑analysis.
– The need to bridge biomedical markers and patient‑reported, function‑oriented outcomes aligned with the WHO healthy aging paradigm.
– South Korea’s rapidly aging population and the expansion of community‑based healthy aging programs, which require standardized evaluation metrics for policy and scale‑up decisions.
– Pragmatic feasibility in busy primary care settings: focusing on measures that are validated, commonly used, or routinely collected (e.g., BP, weight, basic labs, EQ‑5D).
Updated Recommendations and Key Changes vs. Prior Practice
Because this is an initial COS rather than a revision, the key change is introducing a standardized minimum dataset rather than years of prior inconsistency. Compared with common prior practice—where studies selected disparate, sometimes single endpoints—this COS recommends a balanced set across domains.
Notable practical shifts the COS promotes:
– From single‑domain endpoints (e.g., only glucose or only self‑reported function) to a balanced core set including PROs, function, physiologic risk factors, and frailty assessment.
– Explicit inclusion of a culturally relevant traditional medicine score (Kidney‑Deficiency Score) reflecting Korean integrative care contexts—highlighting the COS’s responsiveness to national practice patterns.
Topic‑by‑Topic Recommendations
Implementation principles
– Minimum reporting: Trials and program evaluations of healthy aging interventions in primary care should, as a minimum, measure and report the 12 core outcomes at baseline and at least one follow‑up time point appropriate to the intervention (commonly 6–12 months).
– Measurement instruments: Use validated instruments where available—EQ‑5D for generic quality of life, GDS for depressive symptoms, Lawton IADL for instrumental function, standardized laboratory assays for blood glucose, lipids, liver and kidney function, and the Korean Frailty Index for frailty screening.
– Feasibility: The COS prioritizes measures that are already commonly collected or feasible to add in primary care visits; programs without lab capacity should state this and use available proxies where appropriate.
Suggested measurement schedule (practical exemplar)
– Baseline: All 12 core outcomes
– Short‑term follow‑up (3 months): PROs (EQ‑5D, GDS, self‑rated health), body weight, blood pressure
– Medium‑term follow‑up (6–12 months): full core set including labs and frailty index
Recommendation grades and evidence base
– The COS is a consensus instrument—its recommendations are derived from expert consensus and existing literature rather than a graded evidence review of interventions. The emphasis is on standardization for measurement rather than on therapeutic recommendations.
Special populations and applicability
– The COS targets older adults receiving health‑promotion or preventive interventions in primary care. It may be adapted for institutional settings (e.g., long‑term care) with caveats.
– For patients with severe cognitive impairment or communication barriers, validated proxy assessments (e.g., proxy EQ‑5D) may be used.
Expert Commentary and Insights
From the PMG and Delphi panellists (paraphrased summaries based on Jang et al., 2025):
– Balance and pragmatism: Experts emphasized selecting outcomes that balance clinical importance with feasibility. This explains the inclusion of standard vitals and labs alongside PROs and frailty measures.
– Importance of PROs: Several panel members highlighted the centrality of EQ‑5D and self‑rated health as sensitive indicators of intervention impact on well‑being and functional ability, consistent with WHO healthy aging frameworks.
– Cultural relevance: The inclusion of the Kidney‑Deficiency Score reflects integration of traditional medicine practices in Korean primary care and was favored by panelists for local relevance; some experts noted this may not generalize outside similar integrative systems.
– Controversies: Panelists debated inclusion of performance‑based measures (e.g., gait speed, timed up‑and‑go). While recognized as informative, these were omitted from the core set largely due to feasibility concerns in routine primary care. Experts recommended such measures as optional supplemental outcomes when resources permit.
Areas for future refinement highlighted by experts
– Validation across settings: The COS requires real‑world testing in diverse primary care settings (urban/rural, resource‑limited clinics) to assess feasibility and data completeness.
– Harmonization with international aging initiatives: Experts urged alignment with WHO ICOPE tools and international frailty measures to maximize cross‑country comparability.
Practical Implications for Clinicians and Researchers
How practices and research teams can adopt the COS
– Trials and program evaluations: Incorporate the 12 outcomes into case report forms and reporting plans. Register trial outcomes prospectively to reduce outcome reporting bias.
– Primary care clinics: Where feasible, embed EQ‑5D and GDS as routine screening tools in annual wellness visits for older adults; ensure labs and vitals are recorded in structured fields for quality improvement and program evaluation.
– Data systems: Electronic health record (EHR) templates or registries should include the core outcomes as structured data elements to facilitate aggregation and analysis.
Benefits
– Improved comparability across programs and studies enables meta‑analyses and stronger evidence synthesis for healthy aging interventions.
– Policymakers can make better informed decisions on program funding and scale‑up when outcomes are standardized.
Potential challenges
– Resource limitations: Not all primary care clinics can routinely collect labs or detailed frailty indices. The COS is a minimum—programs should document deviations and consider pragmatic substitutes.
– Cultural generalizability: Some items (Kidney‑Deficiency Score) may be specific to Korean integrative contexts and require adaptation for other countries.
Limitations and Future Directions
The COS authors and external experts note several limitations:
– Consensus, not empirical weighting: The core set reflects expert consensus rather than quantitatively weighted outcome importance across stakeholder groups (e.g., patients, payers).
– Need for implementation research: Studies are needed to evaluate uptake, feasibility, completeness of data, responsiveness to change, and predictive validity for meaningful endpoints (e.g., hospitalization, functional decline).
– Evolution over time: As measurement science advances (digital biomarkers, remote monitoring, shorter PRO instruments) and as international harmonization progresses, the COS should be periodically revised.
Recommended next steps
– Pilot implementation across diverse primary care practices with evaluation of feasibility and data quality.
– International collaboration to harmonize core domains with WHO ICOPE and other COS efforts to facilitate cross‑national evidence synthesis.
– Stakeholder engagement, notably older adults and caregivers, to refine patient‑centered priorities and acceptable measurement burden.
Practical Vignette
Margaret, 72, enrolls in a community healthy‑aging program offered through her primary care clinic in Seoul. Baseline assessments include EQ‑5D, GDS, Lawton IADL, self‑rated health, weight, BP, fasting glucose, lipid profile, liver and kidney function, the Korean Frailty Index, and the Kidney‑Deficiency Score. At 6 months the clinic repeats the full core set. Because the program uses the COS, its results can be compared with other clinics and pooled into regional analyses—helping show whether the program meaningfully improves quality of life, reduces frailty scores, or improves metabolic risk factors.
References
– Jang S, Jeong H, Park J, Ko MM, Jung J. Development of core outcome set for healthy aging treatment in primary care settings. Integr Med Res. 2025 Dec;14(4):101205. doi: 10.1016/j.imr.2025.101205. Epub 2025 Jul 19. PMID: 40896347; PMCID: PMC12391697.
– World Health Organization. World report on ageing and health. WHO; 2015. (available at: https://www.who.int/ageing/publications/world-report-2015/en)
– Williamson PR, Altman DG, Bagley H, Barnes KL, Blazeby JM, Brookes ST, Clarke M, Gargon E, Gorst SL, Harman NL, Kirkham JJ, McNally R, … Tugwell P. The COMET Handbook: version 1.0. Trials. 2017;18(Suppl 3):280. doi:10.1186/s13063-017-1978-4
– EuroQol Group. EuroQol—a new facility for the measurement of health‑related quality of life. Health Policy. 1990; 16(3):199–208.
– Yesavage JA, Brink TL, Rose TL, Lum O, Huang V, Adey M, Leirer VO. Development and validation of a geriatric depression screening scale: a preliminary report. J Psychiatr Res. 1982–83;17(1):37–49.
– Lawton MP, Brody EM. Assessment of older people: self‑maintaining and instrumental activities of daily living. Gerontologist. 1969;9(3):179–186.
– World Health Organization. Integrated care for older people (ICOPE) guidance: person‑centred assessment and pathways in primary care. WHO; 2017. (available at: https://www.who.int/ageing/health-systems/icope/en/)
Conclusion
The 2025 Core Outcome Set for healthy aging interventions in primary care offers a pragmatic, balanced minimum dataset that bridges patient‑reported outcomes, functional measures, and routine clinical biomarkers. Its adoption promises to reduce heterogeneity in outcome reporting, support evidence synthesis, and inform policy and scaling of effective aging interventions. Real‑world implementation studies and international harmonization efforts will be important next steps to ensure the COS achieves its promise across settings.
