Urinary calcium excretion in schoolboys. Ethnic group differences.

: The urinary calcium/creatinine ratio was estimated in two groups of schoolboys--village Arabs and urban Jewish (Ashkenazic) schoolboys, aged 10 to 11 years. Both the mean calcium/creatinine ratio and the frequency of hypercalciuria were higher among the Arab boys, and may be related to the higher incidence of chilidhood urolithiasis in Arab children in Israel.