Affiliation: | 1.German Childhood Cancer Registry (GCCR), Institute for Medical Biostatistics,Epidemiology and Informatics (IMBEI),Mainz,Germany;2.Department of Epidemiology & International Public Health, School of Public Health,Bielefeld University,Bielefeld,Germany;3.Institute for Medical Biostatistics,Epidemiology and Informatics (IMBEI),Mainz,Germany |