Calculate your facility's CMI from your current patient census, compare to state and national benchmarks, and identify where you're leaving Medicare dollars on the table.
Enter your census count in each PDPM/RUG category. We'll calculate your blended CMI and compare it to state and national averages so you can see where you stand.
Medicare Patients by Therapy/Clinical Category (enter headcount)
Weights are illustrative and based on 2024 PDPM averages. Actual weights vary by patient clinical group, comorbidities, and state wage index. Consult your MDS coordinator for facility-specific analysis.
Case Mix Index is the average relative weight of all Medicare patients in your facility. A higher CMI means your patients are more medically complex — and your facility earns more per patient day. Understanding and improving your CMI is one of the highest-leverage financial management activities a SNF administrator can pursue.
CMI is calculated by summing all patient case-weight values and dividing by the number of Medicare patients. A CMI of 1.00 represents the average; anything above 1.00 means you have a more complex census than average.
Each 0.10 increase in CMI translates to approximately $10–14 per Medicare patient day. For a 100-bed facility with 30% Medicare census, that's over $100,000 in annual revenue per 0.10 CMI improvement.
Your CMI is only as good as your MDS documentation. Missed diagnoses, uncoded comorbidities, and under-documented functional deficits all suppress your CMI. Regular MDS audits are essential.
Under PDPM, payment is calculated across PT, OT, SLP, nursing, and non-therapy ancillary components. CMI improvement strategies must address all five simultaneously for maximum impact.
CMI is also a strategic admission tool. Understanding the case weight of prospective patients before admission allows you to model financial impact and make informed case-mix decisions.
CMS publishes facility-level CMI data in the Provider of Services file. Facilities in the bottom quartile of their state often have significant improvement opportunity through documentation improvement alone.
Patient-Driven Payment Model uses five payment components. The table below shows representative case weight ranges for each component's clinical categories.
| Component | Clinical Group | Case Weight Range | Key Drivers |
|---|---|---|---|
| Physical Therapy | Orthopedic Surgery — Lower Extremity | 1.40 – 1.58 | Functional score, primary diagnosis |
| Physical Therapy | Non-Orthopedic Surgery | 1.18 – 1.42 | Cognitive impairment modifier |
| Occupational Therapy | Orthopedic Surgery — Lower Extremity | 1.32 – 1.51 | ADL score, cognitive function |
| Occupational Therapy | Medical Management | 0.98 – 1.26 | Depression, cognitive impairment |
| Speech-Language Path. | Acute Neurologic | 1.48 – 1.76 | Mechanically altered diet, SLP comorbidities |
| Speech-Language Path. | Medical Management | 0.82 – 1.34 | Cognitive, swallowing impairment |
| Nursing | Extensive Services | 1.27 – 1.55 | Trach, vent, IV medications |
| Nursing | Special Care High | 1.14 – 1.38 | Burns, cerebral palsy, septicemia |
| Nursing | Clinically Complex | 0.92 – 1.20 | Dialysis, pneumonia, wounds |
| Non-Therapy Ancillary | High (HIV, ESRD, etc.) | 1.35 – 2.10 | HIV/AIDS, ESRD, multiple high-cost conditions |
| Non-Therapy Ancillary | Low | 0.68 – 1.08 | Standard ancillary needs |
State averages vary significantly due to patient population, urban/rural mix, and hospital referral patterns. Facilities performing below their state average should investigate documentation improvement as a first step.
| State | Avg CMI | Top Quartile | Bottom Quartile | Trend |
|---|---|---|---|---|
| Idaho | 1.07 | 1.22 | 0.91 | ↑ +0.03 |
| Utah | 1.11 | 1.27 | 0.95 | ↑ +0.04 |
| Montana | 1.03 | 1.18 | 0.87 | → flat |
| Wyoming | 1.05 | 1.19 | 0.89 | ↑ +0.02 |
| Oregon | 1.12 | 1.28 | 0.96 | ↑ +0.05 |
| Washington | 1.14 | 1.30 | 0.98 | ↑ +0.06 |
| Colorado | 1.13 | 1.29 | 0.97 | ↑ +0.04 |
| Arizona | 1.10 | 1.25 | 0.94 | → flat |
| California | 1.17 | 1.33 | 1.01 | ↑ +0.07 |
| National Average | 1.09 | 1.24 | 0.93 | ↑ +0.04 |
Source: CMS Provider of Services data, 2024 annual release. Illustrative regional sample — not a complete national listing.