Two big names in health care keep giving each other black eyes. Health Management Associates ( HMA) -- long a Wall Street darling -- threw the latest punch by attacking the research of a celebrated health care analyst. The rural hospital chain issued a statement Thursday accusing UBS analyst Kenneth Weakley of making "materially inaccurate assumptions" that "substantially distorted" the conclusions he reached in a report published this week. HMA has publicly struck out at Weakley at least twice for comparing the company to Tenet ( THC). Weakley gained celebrity status for exposing Tenet's aggressive -- and unsustainable -- business practices 16 months ago. But he is now fielding heat from HMA for questioning its pricing strategies as well. "HMA believes through this report and others, Mr. Weakley is improperly attempting to link HMA with problems experienced by Tenet Healthcare Inc. through innuendo and implication," HMA stated on Thursday. "The company believes that Mr. Weakley's irresponsible actions are causing confusion and misleading investors by insinuating that there is a close connection between HMA and Tenet, while facts and circumstances lead to a different conclusion." HMA jumped 2.4% to $21.76 following the company's rebuttal. Previously, Weakley had pointed to HMA's high list prices as a reason for concern. But he went a step further this week by concluding that such prices had triggered some of the same Medicare "outlier" payments that once made Tenet so profitable. HMA shot back on Thursday by refuting Weakley's figures. The company claimed that its current outlier ratio -- or percentage of Medicare revenue derived from the bonus payments -- is 60% lower than the 4.72% Weakley had calculated. It also said that outlier ratios at its Mississippi hospitals, averaging 5.44% last year, are "substantially below the double-digit percentage reported by Weakley." In addition, it said that its outlier ratio for outpatient services falls a full percentage point below the maximum limit.