Thacher TD, Sempos CT, Durazo-Arvizu RA, et al. - Researchers conducted this case-control study to evaluate the performance of serum alkaline phosphatase (AP) activity in identifying nutritional rickets in calcium-deprived Nigerian children. The sample consisted of children with active rickets (n = 122) and matched control subjects without rickets (n = 119). Data reported that serum AP activity levels in cases and controls were 812 ± 415 and 245 ± 78 U/L, respectively. An AP > 350 U/L effectively distinguished between Nigerian children with and without nutritional rickets. AP is a low-cost biochemical test that could be used to screen for nutritional rickets; however, cut-off values need to be validated in other populations, and laboratory values must be standardized for widespread population studies.