We recently used machine learning techniques to understand key drivers of Medicare Shared Savings Program (MSSP) financial performance. Of the 190-plus objective accountable care organization (ACO) features reviewed, ACO baseline efficiency proved to be the most important financial performance driver we identified. Another way of putting it is that MSSP rewarded inefficient ACOs more than ACOs that have attained efficiency.
You may be asking, “How did you measure baseline efficiency?” The chart below tells an interesting story.
We analyzed ACO baseline efficiency by reviewing ACO baseline expenditures that were unadjusted, risk-adjusted, and geographic-risk-adjusted. Risk-adjusted per capita expenditures were adjusted to account for each ACO’s average risk score and mix of entitlement categories. Geographic risk-adjusted per capita expenditures were adjusted to account for Medicare reimbursement levels in each ACO’s area.
Below are a few interesting notes:
1. Despite adjusting for risk levels, mix of entitlement categories, and reimbursement levels, there is still significant variation in baseline per capita expenditures. See the third column above for this wide range of variation.
2. The Centers for Medicare and Medicaid Services (CMS) has already made MSSP rule changes that balance the rewards between ACOs at different levels of starting efficiencies. Past financial performance in MSSP agreement period 1 may not be a strong indicator of performance in agreement period 2. ACOs should understand how these rule changes affect them.
Beyond baseline efficiency, we found that several other features were strongly associated with gross savings:
1. National fee-for-service (FFS) trends higher than local market trends
2. Location in the Southeast and south central regions
3. Low performance year expenditures for short-term inpatient admissions
4. High baseline per capita expenditures, unadjusted
5. High CMS-hierarchical condition category (HCC) risk scores
However, we also found that these features still explained less than half of the variation in gross savings across ACOs. This may indicate that ACO care management efforts are accounting for some of the remaining variation.