Many physicians enter an ACO with the same question: “What is actually going to change on Monday morning?”
The answer is less dramatic, and more important than expected.
The first 90 days in an ACO rarely involve sweeping changes; patients still need to be seen. Schedules remain full. Clinical priorities remain the same. What changes is the infrastructure surrounding care: access to performance data, care coordination support, quality reporting processes and visibility into patient populations that may need additional attention.
This is where many practices discover that success in value-based care is determined by the workflows that support it. Identifying attributed patients, closing care gaps, managing post-discharge follow-up and understanding quality performance all become part of the daily operating rhythm.
The organizations that see the strongest results are often those that use their first few months to build sustainable processes, engage providers and establish a clear understanding of how value-based care fits into their existing practice operations.
For practices entering their first ACO agreement, the first 90 days are not about transformation. They are about building foundations that make long-term success possible.
Before Day One: The Attribution Gap
The first surprise most physicians encounter is not a new workflow. It is a new patient list they did not know they had.
Patient attribution in most ACOs is claims-based: CMS assigns Medicare beneficiaries to an ACO based on where they have received the plurality of their primary care services, typically through qualifying physician or advanced practitioner visits.
In practice, this means the attributed panel may include patients seen only once over the prior two years, patients splitting care across multiple primary care physicians and patients whose full chronic disease burden is only partially visible in any single provider’s record.
The AMA advises physicians entering an ACO to understand, at minimum, the frequency and quality of data the ACO will provide, and to confirm that claims data covers services delivered both inside and outside the network. That means requesting the attributed patient list early, reviewing it carefully and flagging discrepancies before the performance year gains momentum.
Days 1–30: Understanding the Measurement Framework
The first month is less a clinical overhaul than a fundamental mindset shift from volume to value. In a traditional fee-for-service environment, a productive day is measured by patient throughput and billing complexity. In an ACO, performance is measured by what happens between visits and how frequently preventable crises are avoided.
The first 30 days are spent deconstructing the quality metric scorecard. Whether the ACO operates under MIPS, MSSP or a commercial risk contract, the priority is identifying the specific 10 to 15 quality measures that drive shared savings.
This is rarely about changing how conditions like diabetes or hypertension are treated; it is about ensuring the EHR captures relevant data in a format the ACO’s data aggregator can extract.
Alongside this comes a documentation reality check. If a chronic condition is not documented with appropriate specificity during a given calendar year, it effectively disappears from the patient’s risk profile. This compresses benchmark expenditures and creates the misleading appearance of overspending on a patient who is, in fact, significantly ill.
The task in month one is not to fix the entire system, it is to bring care coordinators, billing staff and clinical teams together to map exactly how data flows from documentation to the ACO’s registry.
Days 31–60: Building the Early-Warning System
By the second month, the initial administrative friction settles and operational priorities come into focus. The most critical workflow to establish during this window is the Transitional Care Management (TCM) protocol.
An unmanaged hospital discharge is a clinical and financial liability. TCM requires initial contact with the patient within two business days after discharge, a face-to-face visit within a specified period and moderate or high medical decision-making during the 30-day service period.
Practices must have a reliable system for learning when attributed patients are admitted to or discharged from any local hospital or emergency department, including facilities entirely outside the practice’s immediate network. Without that infrastructure in place, readmission rates rise and shared savings erode.
This period is also when high-performing practices introduce the daily morning huddle. Taking five to ten minutes before the first scheduled appointment, staff review the day’s schedule not only to see who is coming in, but to actively flag who is overdue for an annual wellness visit, who has an open care gap such as a missed colorectal cancer screening and who had a recent emergency department encounter.
Days 61–90: Stratification and the New Routine
By day 60, the practice should have a reasonably clean patient list and a functioning alert system for hospital discharges. The final stretch of the first quarter is about distinguishing the patients who require intensive coordination from those who do not.
Intensive care management cannot be applied to an entire attributed panel, nor does it need to be. The focus belongs to the top 5% to 10% of highest-risk, highest-utilization patients: those with multiple comorbidities, frequent emergency department visits or complex social determinants of health.
These are the patients for whom the ACO’s centralized resources- dedicated chronic care managers, social workers, behavioral health liaisons, provide the greatest leverage, ensuring that complex cases are no longer managed in isolation.
This phase also marks a permanent shift toward proactive scheduling. Rather than waiting for high-risk patients to initiate contact when a crisis has already developed, the care team begins scheduling them for Annual Wellness Visits (AWV) early in the performance year.
The AWV is among the most valuable tools available in the ACO model: it creates dedicated time to capture risk documentation accurately, close open quality gaps and establishes a preventive care plan before the calendar year gets away from the practice.
The View from Day 91
When the 90-day mark arrives, the initial friction of entering an ACO begins to recede. The contract has not changed the practice of medicine. What it has done is create the infrastructure: data, workflows and team accountability that allows clinical care to be delivered more proactively and measured more accurately.
Shared savings are not guaranteed, and they do not arrive quickly. But by day 90, a well-prepared practice will have the foundations in place to ensure that when reconciliation comes, the results reflect the work that was done.
How Advanced Management USA Approaches the First 90 Days
At Advanced Management USA, we treat the first 90 days not as a period of upheaval, but as the time to build the foundation that makes everything afterward possible. We work alongside your team from the start, putting the right data, workflows, and support in place without pulling your staff away from patients. The first quarter sets the trajectory for everything that follows, and we make sure it’s built right.
It’s also how a practice stays independent. The infrastructure that drives ACO success is expensive and difficult to build alone, and often what pushes practices to sell. We provide that support so practices never have to choose between succeeding in value-based care and keeping their independence. The result is a practice with the capabilities of a large system and the autonomy of an independent one.
That’s what changes on Monday morning: not how you practice medicine, but everything standing behind you when you do.
References
American Medical Association. “Accountable Care Organizations and Value-Based Care.” JAMA. Available at: https://jamanetwork.com/journals/jama/article-abstract/2702593
Centers for Medicare & Medicaid Services. “Medicare Shared Savings Program: Shared Savings and Losses and Assignment Methodology Specifications.” Available at: https://www.cms.gov/files/document/medicare-shared-savings-program-shared-savings-and-losses-and-assignment-methodology-specifications.pdf-2
Centers for Medicare & Medicaid Services. “Medicare Shared Savings Program Guidance and Regulations.” Available at: https://www.cms.gov/medicare/payment/fee-for-service-providers/shared-savings-program-ssp-acos/guidance-regulations
Centers for Medicare & Medicaid Services. “Risk Adjustment.” Available at: https://www.cms.gov/medicare/payment/medicare-advantage-rates-statistics/risk-adjustment
Centers for Medicare & Medicaid Services. “Annual Wellness Visit.” Available at: https://www.cms.gov/medicare/coverage/preventive-services/medicare-wellness-visits/annual-wellness-visit
Centers for Medicare & Medicaid Services. “Transitional Care Management Services.” Medicare Learning Network. Available at: https://www.cms.gov/files/document/mln908628-transitional-care-management-services
