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de Groot JA, Janssen KJ, Zwinderman AH, Moons KG, Reitsma JB.de Groot JA, et al. Among authors: zwinderman ah.Stat Med. 2008 Dec 10;27(28):5880-9. doi: 10.1002/sim.3410.Stat Med. 2008.PMID: 18752256