Crude and adjusted odds ratios (OR) for ALL comparing children with older siblings to children without older sibling, stratified by age groups.

aunivariable conditional logistic regression model.b175 cases, 1382 controls.c130 cases, 1032 controls.d120 cases, 936 controls.ep values for trend were obtained including the variable continuously; the coding for number of older siblings was 0, 1, 2.fmultivariable conditional logistic regression adjusted for maternal age, paternal age and socio-economic status.