de Hoop Esther, Woertman Willem, Teerenstra Steven
Department for Health Evidence 133, Radboud University Medical Centre, PO Box 9101, 6500 HB Nijmegen, The Netherlands.
J Clin Epidemiol. 2013 Dec;66(12):1428. doi: 10.1016/j.jclinepi.2013.07.008. Epub 2013 Sep 8.