IMPORTANCE OF THE SURVEILLANCE METHOD - NATIONAL PREVALENCE STUDIES ON NOSOCOMIAL INFECTIONS AND THE LIMITS OF COMPARISON

OBJECTIVE: To demonstrate the limits of comparison of national prevale nce rates of nosocomial infections. DESIGN AND SETTING: Critical analy sis of prevalence rates and methods of the Nosocomial Infections in Ge rmany (NIDEP) study and other prevalence surveys with particular atten tion to the selection of patients, the qualification and training of t he investigators, and the methods of identifying nosocomial infections . RESULTS: The lowest prevalence rate was found in Germany (3.5 %), th e highest in Belgium (9.3 %). These differences may not be accurate, b ecause Variations in methods allow for differing explanations. CONCLUS IONS: Because of numerous methodological factors, comparison of infect ion rates between countries should be avoided. In contrast to other pr evalence studies, the methodology of the German-NIDEP study permits re gistration of only certain infections, which is the main reason for th e low rate (Infect Control Hosp Epidemiol 1998;19:661-667).