As summarized in the This American Life segment "Who Would Win In A Fight Between A Polar Bear And An Insurance Company?," what impact did HMOs have at their height in the mid-1990s?

In the mid-1990s, HMOs (Health Maintenance Organization) were effective at keeping down the costs of the insurance fee but the overall quality of the health services provided declined deeply, as the coverage for many necessary procedures were denied.

HMOs, like Blue Cross & Blue Shield, are medical insurance groups that provide health coverage for an annual fee.