This is part 3 of an ongoing Pulitzer-nominated series. Click here for the other parts in the series, or to discuss the series as a whole.

Internal documents show that a UnitedHealth subsidiary called NaviHealth set a target for 2023 to keep rehab stays of patients in Medicare Advantage plans within 1% of the days projected by the algorithm. Former employees said missing the target for patients under their watch meant exposing themselves to discipline, including possible termination, regardless of whether the additional days were justified under Medicare coverage rules.

The stringent performance goal was part of a broader effort to reduce expensive nursing home care for frail patients with privatized Medicare plans, the internal documents show. The strategy was conceived and executed by former top Medicare officials whose policies became a blueprint for UnitedHealth to reap hundreds of millions of dollars annually by shredding the government’s safety net with payment denials backed by an algorithm.

Three former case managers said the individual stories behind the algorithmic denials were haunting: An older woman found in the laundry room by her grandson after a stroke, her right side paralyzed, was allotted 20 days of rehab by the algorithm, when the average for severely impaired stroke patients is almost double that. A 78-year-old legally blind man who needed care for a failing heart and kidneys, and then fell in the nursing home, was granted 16 days. Another older man nearing his discharge date after knee surgery was expected to learn how to “butt bump” up and down stairs. If case managers disagreed, and tried to extend a patient’s stay, they ran the risk of missing their targets.