Pulvirenti JJ, Gerding DN, Nathan C, Hafiz I, Mehra T, Marsh D, Kocka F, Rice T, Fischer SA, Segreti J, Weinstein RA. Difference in the incidence of Clostridium difficile among patients infected with human immunodeficiency virus admitted to a public hospital and a private hospital. Infect Control Hosp Epidemiol. 2002 Nov; 23(11):641-7.