Post-discharge surveillance (PDS) for surgical site infections: a good method is more important than a long duration Koek, M B and Wille, J C and Isken, M R and Voss, A and van Benthem, B H, Eurosurveillance, 20, 21042 (2015), https://doi.org/10.2807/1560-7917.ES2015.20.8.21042