National influences on catheter-associated bloodstream infection rates: practices among national surveillance networks participating in the European HELICS project., Hansen, S, Schwab F, Behnke M, Carsauw H, Heczko P, Klavs I, Lyytikäinen O, Palomar M, Riesenfeld Orn I, Savey A, et al. , J Hosp Infect, 2009 Jan, Volume 71, Issue 1, Number 73, (2009)