Some 93 percent of Medicare Part D beneficiaries are overpaying for drug coverage, according to a new study by PlanPrescriber, which helps match seniors with medical plans. Only 7 percent of those studied were enrolled in plans that had the lowest total out-of-pocket costs available, according to the analysis of more than 25,000 user sessions that took place on the company’s website during the 2011 annual enrollment period.

Also according to the study, fewer than 10 percent of beneficiaries were enrolled in the Medicare Advantage plan prescription drug plan with the lowest costs. In the sessions analyzed, PlanPrescriber compared the user’s existing Medicare and Medicare Advantage drug plans, frequency and dosages of medications and zip code. The PlanPrescriber tool then calculated the user’s costs and compared them with the costs of other plans available in his or her area. The study found that the average Medicare beneficiary stood to save $546 per year by enrolling in the most advantageous plan.

“There is a belief among some seniors that ‘Hey, this is all Medicare. It doesn’t make much difference which plan I sign up for,’ ” said Ross Blair, president and CEO of PlanPrescriber in an interview with the Miami Herald. But the PlanPrescriber study found the average Medicare beneficiary could save $546 by choosing the plan with the lowest out-of-pocket costs for his or her drug needs.

The study results demonstrate the importance of carefully reviewing options during the Medicare annual enrollment period, which this year will take place between Oct. 15 and Dec. 7. Unfortunately, each year only about 10 percent of Medicare Part D plan participants elect to change plans, according to a 2010 study by the Robert Wood Johnson Foundation.

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