Validity of routine surveillance data: a case study on Swedish notifications of methicillin-resistant Staphylococcus aureus Stenhem, M and Örtqvist, Å and Ringberg, H and Larsson, L and Olsson-Liljequist, B and Hæggman, S and Kalin, M and Ekdahl, K and the Swedish study group on MRSA epidemiology, Eurosurveillance, 14, 19281 (2009), https://doi.org/10.2807/ese.14.30.19281-en