Three Republican senators have asked Centers for Medicare & Medicaid Services Administrator Mark B. McClellan to delay implementation of new Medicare rules for power wheelchairs.

Finance Committee Chairman Charles E. Grassley (R-IA) requested a postponement to allow for more education of providers and suppliers and to ensure a smooth transition to the new coverage and payment system. The rules are scheduled to take effect Oct. 25.

Sens. Rick Santorum (R-PA) and Arlen Specter (R-PA) also asked for a delay. They want the rules to take effect April 1, 2006. They also requested that new codes not be applied until next July.

Among other changes, the interim final rule would allow physicians and treating practitioners to prescribe a power mobility device. Previously, authority was restricted only to specialists in physical medicine, orthopedic surgery, neurology or rheumatology.