Serum cotinine cut-points for secondhand smoke exposure assessment in children under 5 years: A systemic review.

No studies have calculated serum cotinine age-specific cut-points to ascertained SHS exposure among children under 5 years old. Children's age-specific cut-points are warranted for health research and public health purposes aimed at accurately estimating the prevalence of SHS exposure and attributable burden of disease to such exposure, and at reinforcing 100% smoke-free policies worldwide, both in homes, private vehicles and public places.