"[KFF] found significant variation between companies, with denial rates ranging from as low as 1% to as high as 54%. Among insurers with a high volume of claims, Blue Cross and Blue Shield of Alabama had the highest denial rate for in-network claims at 35%, followed by UnitedHealth Group at 33%. Illinois-based Health Care Service Corp., which runs nonprofit Blue Cross plans in five states, had the third-highest denial rate at 29%."  MORE >>