November DTR: Medicare HMO enrollment

"However, the MMA has some drawbacks, with the number of options and the structure of the new benefit plans posing some confusion for some seniors," says Alan Wright, MD, MPH, vice president of product strategy and business development at Resolution Health Inc., a healthcare data analytic and intervention company.

"Additionally, the MMA has spurred new entrants into the marketplace, placing emphasis on member retention," Wright says.

"With the largest population of seniors, California has the greatest number of enrolled seniors and the largest market share with 37% of the seniors enrolled in Medicare HMOs. Florida and New York have similar market shares at 19% and 22% of all seniors, respectively. Interestingly, New York has the largest growth rate at 18% (from 2003 to 2004) while California and Florida have similar growth rates of 10% and 12%, respectively," says Wright, who cites U.S. Census Bureau data for 2000 and U.S. Census projections for 2005.

-Tracey Walker