EDITOR—Jefferson discussed some of the major flaws of the study by Brachman et al with respect to policies making certain vaccines compulsory in the US military.1 2 Additional shortcomings of the study by Brachman et al have been described in fuller detail elsewhere.3^–5 For example, the often reported rate of 92.5% effectiveness for the anthrax vaccine sounds impressive but should be considered against the actual results in which 99.7% (378/379) of vaccinated workers avoided anthrax infection compared with 96.4% (399/414) of placebo workers. Thus the vaccine protected …