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Peer-Reviewed Science
Since the Centers for Medicare & Medicaid Services (CMS) adopted its revised Organ Procurement Organization (OPO) Conditions for Coverage in 2020, researchers have published a substantial body of peer-reviewed scientific literature clearly demonstrating the Final Rule's performance metrics fail to accurately and fairly measure OPO performance.
The studies identify recurring methodological concerns regarding the validity and fairness of the Final Rule's performance metrics. Alternative approaches provide more stable, equitable, and clinically meaningful assessments of OPO performance.
The category summaries are followed by a chronological list of all the studies.
Category Summaries
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By J. Thomas Rosenthal, Department of Urology, UCLA Medical School: University of California Los Angeles David Geffen School of Medicine, Los Angeles, CA. The author declares no funding or conflicts of interest.
The 2020 Centers for Medicare and Medicaid Services (CMS) Organ Procurement Organization (OPO) rule used an estimate of OPO organ donor potential that included contraindications to organ donation, termed cause, age, and location consistent with donation (CALC). CMS asserted that even though CALC was inaccurate, it could still be used to compare OPOs because it highly correlated with CALC-adjusted to exclude the contraindications. Quantitative bias analysis is required to determine whether CALC can, in fact, be reliably used to make certification decisions under the rule.
Evaluation of the stability of organ procurement organization performance metrics
By J. Schold et al. October 2025 AJT
Using multiple national data sources, the study found that CMS's performance metric known as CALC (Cause, Age, and Location Consistent with Donation) is unstable, with 20%–43% of OPOs changing performance tiers depending on the data source and up to 40% changing tiers from year to year.
By Jon J. Snyder, et al. September 2020 AJT
The study, forewarned that the proposed OPO performance metrics would result in nearly two-thirds of OPOs failing at least one recertification standard, and that the absence of risk adjustment materially affected certification outcomes.
By Jesse. D. Schold et al. August 2024 AJT
CMS's OPO performance metrics are too “fragile” for high-stakes regulatory decisions like OPO decertification because relatively small methodological changes, such as risk adjustment for race, substantially alter OPO rankings.
Stability of New CMS Metrics for Organ Procurement Organizations: Comparison of 2 Consecutive Years
By A. Israni, et al. June 2023 AJT
The study found that 41% of OPOs changed overall CMS performance tiers in just one year, demonstrating that the new performance metrics produce substantial year-to-year instability.
OPO Measured Donation Rate is Highly Volatile Year to Year and Not a Stable Quality Indicator
By J. Schold, R. Lopez June 2023 AJT
OPO donation rates and donor potential vary substantially from year to year, making CMS's reliance on a single year's data an unstable indicator of OPO quality.
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Direct Measurement of DCD Donor Potential By Tom Mone, J. Thomas Rosenthal et al.
April 2025 Transplantation
This proof-of-concept study demonstrated at a single OPO that DCD donor potential can be measured directly from actual referral and clinical data, capturing medical and circumstances-of-death factors that administrative data such as CALC cannot reliably identify.
Direct Measurement of OPO Donor Potential Using Comprehensive Referral Analysis
By Tom Mone, J. Thomas Rosenthal et. al.
Building on the earlier single-OPO study, researchers analyzed 45,458 referrals across six OPOs and demonstrated that direct measurement of donor potential is feasible, accurate and auditable across diverse service areas.
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By J. Schold, et al. June 2023 AJT (from ATC)
The study found that using different data sources to estimate donor potential changed the certification tiers of approximately 20% of OPOs, demonstrating that CMS's CALC methodology is unduly sensitive to the underlying data source.
By J. Schold et al.June 2023 AJT
The study found that when the researchers accounted for medical contraindications, the certification tiers of 29% of OPOs changed, demonstrating that medically contraindicated cases are not evenly distributed across OPO service areas.
National Death Index Users Guide, CDC
National Center for Health Statistics, Hyattsville, MD. 2013
The CDC's National Death Index User Guide emphasizes that death certificate data (the primary data source for CALC) are intended for public health and statistical research and are subject to important restrictions on their use. These cautions underscore that NDI data were not developed as a precision tool for evaluating the performance of individual organizations.
By Kevin O’Connor, Alexandra Glazier July 2021 AJT
The authors argue in an editorial that while CALC may help OPOs identify opportunities for quality improvement, it lacks the precision needed for regulatory evaluation because it relies on error-prone death certificate data and fails to account for nonventilated patients who cannot become organ donors.
By J. Miller, et al.June 2024 ATC
The study developed a model that accurately predicts an OPO's CALC denominator using SRTR data, allowing OPOs to estimate CMS performance years before official CALC data become available.
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Adjusting for race in metrics of organ procurement organization performance
By Jonathan M. Miller et al. August 2024 AJT
The study found that adjusting CMS's OPO performance metrics for race changed the performance rankings of eight OPOs, including two that would no longer face automatic decertification. The authors conclude that incorporating race-adjusted performance measures would produce fairer evaluations while helping OPOs identify opportunities to improve donation rates across different populations.
Population Characteristics and Organ Procurement Organization Performance Metrics
By Rocio Lopez et al. October 2023 JAMA Network Open
The study found that adjusting CMS's OPO performance metrics for age and community deprivation substantially changed OPO tier rankings, with nearly half of OPOs changing tiers at least once over a three-year period.
Impact of Area Deprivation Index on Organ Procurement Organization Performance Metrics
By J. Schold et al. June 2023 AJT
The study found that adjusting CMS's OPO performance metrics for Area Deprivation Index (ADI) changed the performance tiers of 16%–41% of OPOs, indicating that community deprivation significantly influences measured performance. The authors conclude that OPOs serving more socioeconomically disadvantaged populations may be unfairly penalized under the Final Rule and that population characteristics should be incorporated into risk adjustment.
Examination of Racial and Ethnic Differences in Deceased Organ Donation Ratio Over Time in the US
By Amber B. Kernodle, et al. February 2021 JAMA Surgery
The study found that although deceased organ donation increased more rapidly among some racial minority populations between 1999 and 2017, substantial racial and ethnic disparities persisted.
Does Social Capital Explain Community-Level Differences in Organ Donor Designation?
By Keren Ladin, et al. September 2015 Milbank Quarterly
This study, which preceded the Final Rule by five years, found that community-level factors, particularly social capital, explained more than half of the geographic variation in organ donor designation rates.
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By Rocio Lopez et al. November 2024 AJT
The study found that CMS's OPO performance methodology systematically disadvantages larger OPOs, making them far more likely to be classified as underperforming regardless of actual quality. The authors conclude that an observed-to-expected evaluation method provides a more accurate and equitable assessment of OPO performance.
Reducing Bias against Larger Organ Procurement Organizations in Performance Evaluations
By G. Lyden, et al.June 2024 AJT
The study found that an observed-to-expected (O:E) performance model eliminates the CMS methodology's bias against larger OPOs while maintaining its ability to identify underperforming organizations.
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Assessment of National Organ Donation Rates and Organ Procurement Organization Metrics
By Luke J. DeRoos, et al.
December 2020 JAMA Surgery
The study found that OPO performance rankings vary substantially depending on the metric used, indicating that multiple complementary measures are needed to accurately evaluate OPO performance and guide quality improvement.
By James R. Rodrigue et al.July 2026 Transplantation
The study found that OPOs serving more diverse populations are significantly more likely to receive lower CMS performance ratings, indicating that the Final Rule's unadjusted metrics are associated with structural bias that worsens disparities in organ donation and transplantation.
By Ken Kizer, et al. 2022 National Academy of Sciences
The National Academies consensus report concludes that substantial variation in performance across OPOs, transplant centers, and other components of the transplant system contributes to inefficiency and inequity in organ transplantation. The committee favors coordinated, systemwide performance measures and reforms that promote fairness, transparency, equity, and greater organ utilization—an approach that contrasts with the Final Rule's sole focus on OPO performance metrics.