During an American Bar Association (ABA) program on antitrust and health care issues on October 1, 2012, U.S. Federal Trade Commission (FTC) Deputy Director for Health Care and Antitrust, Leemore Dafny, said that the FTC will focus on how patients purportedly react to price increases, as measured by "diversion ratios," when deciding which hospital mergers to investigate further for potential anticompetitive effects.
Dafny stated that the FTC will focus on diversion ratios rather than geographic markets because relying on geographic market overlaps in hospital mergers may do a poor job of identifying the true source of potential competition problems. Instead, the FTC has and will continue to evaluate hospital mergers to look at whether patients would be willing and able to substitute one hospital for the other if one hospital decided to raise prices for services, using the diversion ratio or the proportion of patients who would switch between them in response to a change in prices. Importantly, the diversion ratio does not rely on any one particular geographic market definition to give the FTC what it believes to be an accurate idea of how a hospital merger might affect competition.
To the extent the FTC considers geography, its staff begins by examining the primary service area of the hospitals – the area from which the hospitals draw about 75 percent of their patients – when conducting a preliminary evaluation of a merger to determine whether overlaps exist. According to Dafny, the more significant the overlaps, the higher the likelihood of a potential competition problem.