Steensel-Moll, H.A. van

leukaemia study childhood incidence patient childhood leukaemia control children pregnancy cancer mother exposure disease diagnosis parent factor infection netherland period group analysis table birth occupation questionnaire child response number risk factors space case-control chemical case-control study method father population question result month malignancy difference cluster analysis erasmus university rotterdam incidence rates region treatment interval distribution dutch trend paediatrician stewart addendum epidemiology category province cluster radiation dclsg leukaemic patients distance development birth order miscarriages response rates separation association time space hydrocarbon-related family order class lymphoma rotterdam mantel leukemie aetiological factors childhood malignancies family size alcohol