RT Journal Article SR Electronic T1 Race/ethnicity and the risk of childhood leukaemia: a case–control study in California JF Journal of Epidemiology and Community Health JO J Epidemiol Community Health FD BMJ Publishing Group Ltd SP 795 OP 802 DO 10.1136/jech-2014-204975 VO 69 IS 8 A1 Sona Oksuzyan A1 Catherine M Crespi A1 Myles Cockburn A1 Gabor Mezei A1 Ximena Vergara A1 Leeka Kheifets YR 2015 UL http://jech.bmj.com/content/69/8/795.abstract AB Background We conducted a large registry-based study in California to investigate the association between race/ethnicity and childhood leukaemia focusing on two subtypes: acute lymphoblastic leukaemia (ALL) and acute myeloid leukaemia (AML).Methods We obtained information on 5788 cases and 5788 controls by linking California cancer and birth registries. We evaluated relative risk of childhood leukaemia by race and ethnicity of the child and their parents using conditional logistic regression, with adjustment for potential confounders.Results Compared with Whites, Black children had lower risk of ALL (OR=0.54, 95% CI 0.45 to 0.66) as well as children of Black/Asian parents (OR=0.31, 95% CI 0.10 to 0.94). Asian race was associated with increased risk of AML with OR=1.643, 95% CI 1.10 to 2.46 for Asian vs Whites; and OR=1.67, 95% CI 1.04 to 2.70 for Asian/Asian vs White/White. Hispanic ethnicity was associated with increased risk of ALL (OR=1.37, 95% CI 1.22 to 1.52). A gradient in risk of ALL was observed while comparing Hispanic children with both parents Hispanic, one parent Hispanic and non-Hispanic children (p Value for trend <0.0001). The highest risk of ALL was observed for children with a combination of Hispanic ethnicity and White race compared with non-Hispanic whites (OR=1.27, 95% CI 1.12 to 1.44). The lowest risk was observed for non-Hispanic blacks (OR=0.46, 95% CI 0.36 to 0.60). Associations for total childhood leukaemia were similar to ALL.Conclusions Our results confirm that there are ethnic and racial differences in the incidence of childhood leukaemia. These differences indicate that some genetic and/or environmental/cultural factors are involved in aetiology of childhood leukaemia.