Paternal Smoking and Risk of Childhood Acute Lymphoblastic Leukemia: Systematic Review and Meta-Analysis

Figure 3

Clear positive dose-response associations between paternal smoking and childhood ALL found from the literature. Note: Among all the 18 studies included in this meta-analysis, two did not present dose-response analysis [32, 43], 10 did not find clear dose-response trend, and the remaining six studies reported clear dose-response trends [23, 33, 35, 37, 41, 42], which were presented in this figure. CPD: cigarettes per day; PY: pack years; the figure for Chang et al. 2006 [23] was estimated from their report that, for paternal preconception smoking, an OR of 1.03 (95% CI: 1.00–1.06) was associated with a one-CPD increment, and an OR of 1.34 (95% CI: 1.02–1.74) with 10-CPD increment, and the figure for Sorahan et al. 1995 [35] was estimated from their report of an OR of 1.16 (95% CI: 1.06–1.27) for change of one level of prenatal use of tobacco products.