Participation Models
The CMS Innovation Center designs and tests pilot programs called Alternative Payment Models (APMs), which reward health care providers for delivering high-quality, coordinated care. Understanding how participation works is essential for organizations considering the ACCESS Model.
ACCESS Is Voluntary
The ACCESS Model is a voluntary model. Organizations that are Medicare Part B–enrolled providers or suppliers can choose to apply to participate. You select which clinical tracks to join and can work with CMS on the terms of your participation.
Voluntary vs. Mandatory Models
CMS Innovation Center models can be either voluntary or mandatory, depending on their design and evaluation needs.
Voluntary Models
Voluntary models allow participants (such as providers or payers) to choose whether they want to take part. These models typically require potential participants to complete a rigorous, competitive application process.
Benefits of voluntary participation:
- Organizations can choose which model(s) they wish to participate in
- Participants can typically end their participation early if needed
- Allows CMS and participants to investigate new concepts or designs
- More operationally feasible for testing innovative approaches
Considerations:
- May be more susceptible to selection bias
- Results may reflect participant readiness more than the model's potential impact
- Evaluation results may not generalize as well to non-participants
Mandatory Models
Mandatory models identify and require specific providers or other organizations to participate, potentially through random selection of geographic areas. Those selected are subject to the model's terms and conditions for the duration of the pilot program.
Benefits of mandatory participation:
- Reduces selection bias in evaluation
- May have a better chance of achieving cost savings
- Results are more likely to be generalizable to a larger population
- Participants represent different types of providers across different geographic areas
Considerations:
- Typically established through rulemaking
- Less flexibility for participants
- May require rulemaking for substantial changes
Comparison Table
| Aspect | Voluntary Participation | Mandatory Participation |
|---|---|---|
| How to Join | Participants choose to participate and complete an application process | Participants are selected by CMS using criteria established in the model design |
| Evaluation | Can be subject to selection bias (overrepresentation of favorable outcomes) | More generalizable results across different provider types and geographies |
| Model Terms | May offer more favorable terms and flexibilities to encourage participation | Allows CMS to test arrangements with higher levels of risk |
| Flexibility | Participants can typically withdraw if the model isn't working for them | Participants remain in the model for its duration |
How ACCESS Voluntary Participation Works
Choose to Apply
Organizations decide whether to apply based on their capabilities, patient population, and strategic goals. There's no requirement to participate.
Select Clinical Tracks
Applicants choose which of the four clinical tracks (eCKM, CKM, MSK, BH) they want to participate in. You can apply for one track or multiple tracks.
Application Review
CMS reviews applications on a rolling basis. Organizations must demonstrate they meet eligibility requirements and have the necessary clinical and technical capabilities.
Participation Terms
Approved organizations work with CMS on participation terms. You can add additional tracks after initial approval, subject to CMS review.
Key Terms Defined
What is a voluntary model?▼
A CMS Innovation Center model (pilot program) that invites providers, payers, accountable care organizations, or states to apply to participate. Participants may be able to choose to leave before testing is completed.
What is a mandatory model?▼
A CMS Innovation Center model (pilot program) that requires a defined set of eligible participants to take part. Participants do not generally have an option to leave the model before testing is completed.
What is generalizability?▼
The degree to which a model's results would work with a much larger (possibly nationwide) group of participants.
What is selection bias?▼
When a model does not have a representative group of providers, payers, or states, which can skew outcomes and limit the generalizability of results.
ACCESS and Other Payment Models
ACO Interaction
ACCESS is designed to complement existing ACO and risk-bearing arrangements by incentivizing ACOs to leverage technology-enabled care to meet quality and savings goals.
ACO Benchmark Impact
For 2026 and 2027, CMS anticipates no impact from ACCESS Outcome-Aligned Payments (OAPs) on ACO benchmark and performance year calculations for the Medicare Shared Savings Program and ACO REACH. Beginning in 2028, expenditures associated with ACCESS OAPs will be included in ACO benchmark and performance year calculations.
MIPS and Advanced APM Status
CMS does not expect ACCESS to qualify as an Advanced Alternative Payment Model (A-APM). CMS anticipates that ACCESS services would not contribute to MIPS reporting obligations.
From Voluntary to Mandatory: A Case Study
The CMS Innovation Center sometimes uses a mandatory participation approach for a successor model after first testing the approach with a voluntary model.
Example: Episode-Based Payment Models
The mandatory Transforming Episode Accountability Model (TEAM) builds on lessons learned from prior models:
- BPCI Initiative — Initial bundled payments testing
- BPCI Advanced — Fully voluntary model
- CJR Model — Primarily mandatory model
- TEAM — Mandatory model building on prior successes
These models demonstrated cost savings, more appropriate hospital discharge decisions, and reductions in avoidable rehospitalizations. Before implementing TEAM with mandatory participation, CMS analyzed successes and failures of earlier tests to ensure participants would be ready.
Future of ACCESS
If the ACCESS Model is found to improve quality without increasing costs—or to reduce costs without harming quality—and the CMS Office of the Actuary certifies those findings, the Secretary of Health and Human Services may consider expanding or making the model permanent through rulemaking.
Benefits of ACCESS Voluntary Structure
For Organizations
- Lower risk entry — Test technology-supported care approaches without mandatory commitment
- Flexibility — Choose tracks that align with your capabilities and patient population
- Scalability — Start with one track and expand as you build experience
- Learning opportunity — Gain experience with outcome-aligned payments in a supportive environment
For Patients
- Choice — Patients voluntarily enroll with ACCESS organizations
- Protection — All Medicare rights, coverage, and benefits are preserved
- Options — Can work with multiple ACCESS organizations for different conditions
- Transparency — CMS directory helps patients make informed choices
For the Healthcare System
- Innovation testing — Evaluates new payment approaches in real-world settings
- Evidence building — Generates data on technology-supported care effectiveness
- Cross-payer alignment — Creates models that other payers can adopt
Frequently Asked Questions
Can we leave ACCESS if it's not working for our organization?▼
As a voluntary model, organizations have more flexibility than in mandatory models. However, specific terms for withdrawal should be discussed with CMS during the application and participation agreement process. Consistent participation is important for model evaluation.
Do we have to participate in all clinical tracks?▼
No. Organizations can choose to participate in one or more clinical tracks based on their capabilities and patient population. You can also apply to add additional tracks after initial approval.
Can patients be required to participate?▼
No. Patient participation is completely voluntary. Patients choose whether to enroll with ACCESS organizations, and they retain all standard Medicare benefits and protections regardless of their decision.
What happens to patients in the control group?▼
A small share of patients who try to enroll may be randomly assigned to a control group for evaluation purposes. Individuals in the control group continue to have full access to all regular Medicare services and can work with their usual health care providers.
How does voluntary participation affect evaluation?▼
Voluntary models can be subject to selection bias, but CMS uses various methods to account for this in evaluation. The model's design includes control groups and risk adjustment to produce meaningful results.
Resources
CMS: Voluntary vs Mandatory Participation
Official CMS explanation of participation models in Innovation Center programs
ACCESS Model Overview
Official CMS Innovation Center page for the ACCESS Model
ACCESS FAQs
Comprehensive answers to common ACCESS Model questions
Next Steps
Check Eligibility Requirements
Review what's needed to participate in ACCESS
Explore Clinical Tracks
Learn about the four condition areas ACCESS addresses
Official Documents
Download the RFA and other official materials