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Incident

Post-acute care denials rose as UnitedHealthcare automated prior authorization; lawsuit targets nH Predict

A class action alleges UnitedHealth used naviHealth's nH Predict model to cut off post-acute care; a Senate investigation found UnitedHealthcare's post-acute denial rate nearly tripled while it automated prior authorization.

Sources checked when written 26 September 2026

TierThe automation stayed up and kept producing output that was wrong or went unchecked; there was no outage to fall back from. How tiers are assigned.

What happened

In November 2023 families of two deceased Medicare Advantage members filed a proposed class action in Minnesota alleging that UnitedHealth used nH Predict to override physicians and end post-acute coverage, that the model had a 90% error rate, and that the insurer relied on only about 0.2% of members appealing. naviHealth said the tool is a guide, not used to make coverage determinations. These are allegations. In February 2025 Judge John Tunheim dismissed five of seven counts but let contract and good-faith claims proceed, calling the appeals process futile. Separately, the Senate Permanent Subcommittee on Investigations reported in October 2024 that UnitedHealthcare's post-acute prior-authorization denial rate rose from 8.7% in 2019 to 22.7% in 2022 while its overall denial rate stayed about 7.5%, during a period of automation initiatives. One internal model test noted an increase in adverse determinations. CMS stated in February 2024 that a length-of-stay prediction alone cannot be the basis to terminate post-acute care.[1,2,3,4]

Documented harm

Complaint alleges patients were discharged from care facilities or paid out of pocket; not adjudicated.

What it teaches

Sources

  1. UnitedHealth uses faulty AI to deny elderly patients medically necessary coverage, lawsuit claims. CBS News, 20 November 2023. Secondary Journalism · link checked 2026-09-26
  2. Federal judge trims AI denial lawsuit against UnitedHealth Group. Courthouse News Service, 13 February 2025. Secondary Journalism · link checked 2026-09-26
  3. Refusal of Recovery: How Medicare Advantage Insurers Have Denied Patients Access to Post-Acute Care. U.S. Senate Permanent Subcommittee on Investigations (Majority Staff), 17 October 2024. Primary Official report · link checked 2026-09-26
  4. Frequently Asked Questions related to Coverage Criteria and Utilization Management Requirements in CMS Final Rule (CMS-4201-F) (HPMS memo). Centers for Medicare & Medicaid Services, 6 February 2024. Primary Guidance · link checked 2026-09-26

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