Suppliers shortchange themselves on standard wheelchairs, federal watchdog finds. You could be losing $977 per K0823 claim if you're not coding correctly, according to a new HHS Office of Inspector General report. That's how much suppliers who downcoded standard wheelchair claims lost on average, the OIG says in the study, "Miscoded Claims for Power Wheelchairs in the Medicare Program." In the first half of 2007, wheelchair suppliers miscoded 8 percent of power wheelchair claims overall, the OIG found. About 3 percent were upcoded, 4 percent were downcoded, and OIG reviewers couldn't determine a coding level for 1 percent. Three-fourths of power wheelchair claims under Medicare fall into the K0823 category, the OIG explains. In 2007, they had a fee schedule amount of $4,024. Suppliers furnishing standard chairs shortchanged themselves more with downcoding -- $977 on average -- than they gained with upcoding -- $437 on average. But that changed when suppliers miscoded complex rehab chairs, the OIG notes. Wheelchair dealers gained $1,081 more on average when they upcoded versus losing $881 on downcodes. One reason: There are a wider variety of complex chairs. In 2007, Medicare covered 276 models of complex rehab chairs under 26 HCPCS codes, the OIG notes. The fee schedule amounts ranged from $4,132 to $11,965. More to come: The OIG conducted the coding accuracy study as part of a larger project researching wheelchair reimbursement, it notes. Expect forthcoming reports on its other wheelchair topics, including suppliers' costs, documentation, and billing accuracy. The OIG stops short of making recommendations based on its findings, but it does note that the Centers for Medicare & Medicaid Services should furnish provider education to reduce coding errors. Note: The report is online at www.oig.hhs.gov/oei/reports/oei-04-07-00403.pdf.