Considering the prevalence of H. Pylori infection 50% and iron deficiency anemia 70%,44 we anticipate H. Pylori related anemia in 50% of infants and children in this community. We expect a reduction in prevalence of H. Pylori related iron deficiency anemia after therapy with antibiotic plus iron therapies 25%. To detect a difference of this magnitude at 5% level and at 80% power the sample size is calculated as follows: