RT Journal Article SR Electronic T1 Medicare Claims and Anesthesia Clinical Research: A Perfect Match JF Regional Anesthesia & Pain Medicine JO Reg Anesth Pain Med FD BMJ Publishing Group Ltd SP 259 OP 261 DO 10.1016/S1098-7339(03)00195-0 VO 28 IS 4 A1 Jeffrey H. Silber YR 2003 UL http://rapm.bmj.com/content/28/4/259.abstract AB