Josephine van Dongen

Chapter 2 42 while considering information maintained by other variables 4 . FMI in our dataset was around 37%. Then, multiple imputation was repeated, 22 new datasets were created for covariates used for survival analyses, again including auxiliary information. We used the STROBE Statement Checklist for repor ting of cohor t studies. http://www.strobe- statement.org References 1. Freedman SB, Eltorky M, Gorelick M. Evaluation of a Gastroenteritis Severity Score for Use in Outpatient Settings. Pediatrics. 2010;125(6):e1278-e1285. doi:10.1542/peds.2009-3270 2. Schnadower D,Tarr PI, Gorelick MH, et al.Validation of the modified vesikari score in children with gastroenteritis in 5 US emergency depar tments. J Pediatr Gastroenterol Nutr. 2013;57(4):514-519. doi:10.1097/MPG.0b013e31829ae5a3 3. Hardt J, Herke M, Leonhar t R. Auxiliary variables in multiple imputation in regression with missing X: A warning against including too many in small sample research. BMC Med Res Methodol . 2012;12:1-13. doi:10.1186/1471-2288-12-184 4. Madley-Dowd P, Hughes R, Tilling K, Heron J. The propor tion of missing data should not be used to guide decisions on multiple imputation. J Clin Epidemiol. 2019;110:63-73. doi:10.1016/j.jclinepi.2019.02.016