TI - WHeels PT - JOUR DP - 2010 TA - Archives of Internal Medicine pages = {820}, VI - 170 IP - 9 AID - 10.1001/archinternmed.2010.83 [doi] 4100 - http://dx.doi.org/10.1001/archinternmed.2010.83 SO - Archives of Internal Medicine May 10, 2010 170(9):820