UnitedHealth Group Inc. systematically cut what it paid for ER visits and mental healthcare to doctors outside of its network, sparking internal tension over how those changes were handled and the potential effect on members, newly unsealed court documents show. The records open a window into the workings of its UnitedHealthcare unit, the largest U.S. health insurer, and shed light on a bitter battle between financial heavyweights in the $5 trillion U.S. medical system.
