DocumentedAlgorithmic Care Denial (Healthcare)July 2023United States

Cigna PxDx Algorithm Allegedly Used to Deny Claims in Bulk

Following a ProPublica investigation, a class action (Kisting-Leung v. Cigna) alleged Cigna used an automated system called PxDx to reject large batches of claims, with company doctors signing off without opening patient files. ProPublica reported more than 300,000 payment requests denied over two months in 2022, averaging about 1.2 seconds per claim. CAVEAT: Cigna publicly disputes that PxDx involves AI or machine learning, describing it as long-standing code-matching technology. This entry is retained with that dispute stated explicitly; it sits at the boundary of AI versus automated algorithm.

AI system:PxDx (procedure-to-diagnosis) review system

Impact

Triggered US House and Senate inquiries into automated claim denials; a frequently cited example of automated decision-making in insurance.

Outcome

In March 2025 a federal judge allowed key claims to proceed. Case ongoing.

Sources

  1. Source 1CBS Newswww.cbsnews.com/news/cigna-algorithm-patient-claims-lawsuit/
  2. Source 2Healthcare Divewww.healthcaredive.com/news/cigna-lawsuit-algorithm-claims-denials-california/688857/
  3. Source 3Courthouse Newswww.courthousenews.com/judge-advances-class-claims-over-cigna-use-of-automated-algorithm-to-deny-benefits/

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