Population Health Analytics

The Centers for Medicare & Medicaid Services (CMS) is preparing to launch the ACCESS Model — Advancing Chronic Care with Effective, Scalable Solutions — on July 5, 2026. ACCESS is a 10-year voluntary program that tests a new approach to Medicare payment: rather than reimbursing for specific activities or services, organizations receive a recurring payment for managing a patient’s qualifying chronic condition, with payment tied to achieving measurable health outcomes. Full payment requires that at least 50% of aligned patients meet condition-specific targets in year one, with thresholds increasing over time.

Technology companies can participate directly in ACCESS — a meaningful new entry point into Medicare value-based care — and for those organizations, the central challenge is not simply identifying who is eligible. It is understanding who can be meaningfully helped, and how. This is precisely the kind of problem the Johns Hopkins ACG System was designed to address.

A Population Defined by Multimorbidity

The chronic conditions at the center of ACCESS — hypertension, diabetes, chronic kidney disease, cardiovascular disease, obesity, musculoskeletal conditions and behavioral health diagnoses — impact more than two-thirds of Medicare fee-for-service beneficiaries. For many beneficiaries, the question is not which chronic condition they have, but how many, and how they interact.

The ACG System was built around this reality. Rather than organizing populations by a single diagnosis, it takes a whole-person approach rooted in multimorbidity: patients are grouped into clinically meaningful segments — Patient Need Groups (PNGs) — that reflect the full burden of illness, disease complexity, and expected resource use. Two patients with hypertension and diabetes may appear similar, but within the PNG framework, one may be in PNG05 (Multimorbidity, Medium Complexity) while another with additional complications lands in PNG10 (Multimorbidity, High Complexity). The diagnoses on paper may look similar; the care needs, intervention requirements, and realistic outcome expectations are not.

Balancing Impactability with Eligibility

For organizations participating in ACCESS, one of the earliest and most consequential decisions is cohort construction: which patients to align, enroll, or prioritize for intervention. The eligible population, as noted, is large. But eligibility alone is not a sufficient guide. Within any eligible population there is wide variation in clinical complexity, readiness for intervention, and likelihood of achieving the outcomes ACCESS measures.

The ACG System helps navigate that variation on two levels. First, PNG segmentation gives organizations a structured view of who is in their population and how complex their needs are. Second, the ACG System’s predictive risk models identify patients at rising risk — those most likely to experience near-term clinical events where proactive intervention can measurably change what happens next. A case study from a health care organization in the UK illustrates the consequence of missing this group: by focusing only on the highest-acuity patients, that organization would have missed nearly 46 percent of those at high risk of hospitalization or elevated cost.

Layered on top of segmentation and risk, ACG Care Modifiers identify actionable drivers of outcomes — medication adherence gaps, care coordination risk, behavioral health comorbidity, and gaps in preventive care — helping organizations match patients with the right level of intervention rather than enrolling them uniformly. Together, these tools help answer not just who is eligible, but who is both eligible and impactable, and what kind of support is most likely to make a difference.

The ACG System has been used by health plans, health systems and technology companies for decades — embedded as an analytics layer within the data environments and platforms organizations are already operating, rather than requiring new infrastructure. Its structured, rules-based logic produces outputs that can be examined, validated, and explained, giving organizations a clinically grounded foundation they can build on and stand behind.

Final Thoughts

ACCESS represents a genuine shift in how Medicare pays for chronic condition management — one that rewards organizations that can demonstrate real, measurable improvement in their patients’ health. It requires knowing the population: who they are, how complex their needs are, and where the opportunity to make a real difference actually lies. The ACG System brings the depth of insight that makes that kind of population understanding possible.

To learn more about how the ACG System can support your ACCESS strategy, visit hopkinsacg.org or contact us at acginfo@jh.edu. If you are a current ACG System customer, please reach out to your Account Manager.

Resources

The resources below provide additional details on the ACCESS Model and key components of the ACG System:

• CMS ACCESS Model overview
• CMS Technical FAQ
• ACG Risk Stratification Handbook
• ACG Whole Population Segmentation Guide
• CMS 5 Key Strategies Guidebook