RESULTS:
We included 29 studies yielding 28,804 Acute Lymphoblastic Leukemia (ALL), 3,208 Acute Myeloblastic Leukemia (AML) and 27,650 "any" leukemia (denoting joint reporting of all subtypes) cases. According to individual-level composite SES indices, children from low SES suffered from nearly 2-fold higher death rates from ALL (pooled RR: 1.83, 95%CI: 1.00-3.34, based on four study arms); likewise, death RRs derived from an array of lower area-level SES indices ranged between 1.17 and 1.33 (based on 11 study arms). Importantly, the survival gap between higher and lower SES seemed wider in the U.S.A, with considerably (by 20% to 82%) increased RRs for death from ALL in lower SES. Regarding AML, poorer survival was evident only when area level SES indices were used. Lastly, remoteness indices were not associated with survival from childhood leukemia.