SPRINGFIELD, Mass. (AP) — A Massachusetts anesthesiologist has been accused of fabricating results in nearly two dozen published studies that claimed to show after-surgery benefits from painkillers including Vioxx and Celebrex. Dr. Scott Reuben, who is on leave from Springfield's Baystate Medical Center, studied the use of more than one type of drug to relieve pain and speed recovery after surgery. Baystate said a routine review in May found that some of Reuben's research was not approved by an internal hospital review board. Further investigation found 21 papers published in anesthesiology journals between 1996 and 2008 in which Reuben made up some or all data. "Dr. Reuben deeply regrets that this happened," his attorney, Ingrid Martin, said. "Dr. Reuben cooperated fully with the peer review committee. There were extenuating circumstances that the committee fairly and justly considered." The hospital has asked the journals to retract the studies, some of which reported favorable results from painkillers including Pfizer Inc.'s Bextra, Celebrex and Lyrica and Merck & Co. Inc.'s Vioxx. His studies also claimed Wyeth's antidepressant Effexor could be used as a painkiller. Vioxx and Bextra — part of a group of painkillers know as Cox-2 inhibitors — were pulled from the market amid mounting evidence they increased the risk of heart attack, stroke and death. Celebrex is the only Cox-2 inhibitor still on the market. Lyrica is a treatment for fibromyalgia. Pfizer gave Reuben five research grants between 2002 and 2007. He also was a member of the company's speakers bureau, giving talks about Pfizer drugs to colleagues. Pfizer said in a statement it was "not involved in the conduct of any of these independent studies or in the interpretation or publication of the study results." The journal Anesthesia & Analgesia retracted 10 of Reuben's studies last month. The journal Anesthesiology said it retracted three. "Doctors have been using (his) findings very widely," said Dr. Steven Shafer, editor of Anesthesia and Analgesia. "His findings had a huge impact on the field." Shafer said researchers would re-examine the literature and may be forced to repeat clinical trials.