145 Nosocomial infections (NIs) are one of the most seri- ous patient safety issues in health care today. The incidence of NIs has been estimated at approxi- mately 2 million cases annually. 1 More than 500,000 of these infections occur in intensive care units (ICUs), and most are associated with the presence of an invasive device (such as a central line or ventila- tor). 2 Although fewer patients were admitted to US hospitals in 1995 compared with 1975 (36 million vs 38 million) and the average duration of stay decreased (7.9 days to 5.3 days), the national NI rate has risen. In 1975, there were 7.2 NIs per 1000 patient-days compared with 9.8 per 1000 in 1995, an increase of 36%. 3 In addition, it has been esti- mated that there are approximately 90,000 deaths attributed to NIs annually, ranking it as the fifth-lead- ing cause of death in acute care hospitals. 4 However, the total cost of NIs to society is not clear. Furthermore, an aim of Healthy People 2010 is to reduce NIs in ICUs by 10% (objectives 14-20). 5 To meet this goal, it is essential that the effectiveness and efficiency of prevention and control strategies be carefully evaluated so that interventions with demon- strated value can be implemented. Interventions that are the best candidates for widespread implementa- tion must not only work (ie, be associated with reduced infections) but must also be feasible. One important component of feasibility is to ensure that A systematic audit of economic evidence linking nosocomial infections and infection control interventions: 1990-2000 Patricia W. Stone, RN, PhD a Elaine Larson, RN, PhD, FAAN, CIC a Lina Najib Kawar, RN, MSN, PhD(c) b New York, New York Background: Nosocomial infections (NIs) are a serious patient safety issue. Infection control personnel are responsible for imple- menting interventions to reduce this risk. The purpose of this systematic review was to audit the published economic evidence of the attributable cost of NIs and interventions conducted by infection control professionals and to evaluate the methods used. Economic evaluation methodology and recommendations for standardization are reviewed. Methods: A search of MEDLINE and HealthSTAR with medical subject headings or text words “nosocomial infections,” “infection control,” or “hospital acquired infections” cross-referenced with “costs,” “cost analysis,” “economics,” or “cost-effectiveness analy- sis” was conducted. Published review articles were also searched. Inclusion criteria included articles published between 1990 and 2000 that contained an abstract and original cost estimate and were written in English. Results were standardized into a common currency. Results: Fifty-five studies were eligible. Approximately one quarter examined NIs in intensive care patients (n = 13). Most studies were conducted from the hospital perspective (n = 48). The costs attributable to bloodstream (mean = $38,703) and methicillin- resistant Staphylococcus aureus infections (mean = $35,367) were the largest. Conclusions: Increased standardization and rigor are needed. Clinicians should partner with economists and policy analysts to expand and improve the economic evidence available to reduce hospital complications such as NI and other adverse patient/staff outcomes. (Am J Infect Control 2002;30:145-52.) From Columbia University, School of Nursing, a and University of Rochester, School of Nursing. b Reprint requests: Patricia W. Stone, RN, PhD, Columbia University, School of Nursing, 630 W 168th St, Mailbox 6, New York, NY 10032. Copyright © 2002 by the Association for Professionals in Infection Control and Epidemiology, Inc. 0196-6553/2002/$35.00 + 0 17/46/121099 doi:10.1067/mic.2002.121099