Amanda Hite says she felt "really healthy" when she applied recently for health insurance. But Anthem Blue Cross and Blue Shield denied her, because she had seen a chiropractor a few months earlier for a sore back and later had visited an emergency room because of back pain.

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"I was surprised and let down," said Hite, 34, of Lexington, Ky., who didn't think her periodic back pain would be enough to keep her from buying health insurance.

Hite's case isn't unusual. Many of the plans offered by Anthem Blue Cross in Kentucky reject about one in five applicants, according to data provided by insurers to the federal Department of Health and Human Services. Rival insurers in the state have even higher denial rates: Humana rejects 26% to 39% of applications in Kentucky, while UnitedHealthcare denies 38% to 43%.

Citing its own 2009 study, America's Health Insurance Plans, an industry trade group, says 87% of people who apply nationally for individual coverage are offered a policy. That figure, however, includes people who are turned down for one policy but offered another that may cost more or have fewer benefits.

The federal website contains denial rates in all 50 states, the District of Columbia and U.S. Territories, and is updated periodically. The most current information is for the first three months of 2011. The data show that denial rates routinely exceed 20% and often are much higher, according to a Kaiser Health News review of 20 of the most populous states and the District of Columbia. The data reflect applications that are turned down for any reason.

The information provides fresh evidence of the challenges facing people buying individual health insurance. It also shows the likelihood of whether consumers are approved for a policy depends on which state they live in and the insurer they choose.

Also, the same insurer can have vastly different denial rates in different states. For example, Kaiser Permanente denied 32% of applications in Maryland but 17% in Colorado. (Kaiser Health News is not affiliated with Kaiser Permanente.)

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