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Wanner M, Götschi T, Martin-Diener E, Kahlmeier S, Martin BW.Wanner M, et al. Among authors: kahlmeier s.Am J Prev Med. 2012 May;42(5):493-502. doi: 10.1016/j.amepre.2012.01.030.Am J Prev Med. 2012.PMID: 22516490Free article.Review.