Public health nutrition
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Public health nutrition · Jun 2002
Randomized Controlled Trial Clinical TrialA randomised trial in Mali of the effectiveness of weekly iron supplements given by teachers on the haemoglobin concentrations of schoolchildren.
To assess the effect on the haemoglobin concentrations of schoolchildren of weekly iron tablets administered by teachers. ⋯ Weekly iron tablets given by teachers prevented a general fall in the haemoglobin concentrations of untreated children, and led to a small but statistically significant rise among treated children. Young children benefited more than children aged >or=12 years, and girls benefited more than boys.
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Public health nutrition · Jun 2002
Comparative StudyValidation and calibration of food-frequency questionnaire measurements in the Northern Sweden Health and Disease cohort.
To evaluate the reproducibility of, and to compare and calibrate, diet measures by the Northern Sweden 84-item food-frequency questionnaire (FFQ) with measures from 24-hour diet recalls (24-HDR). ⋯ The Northern Sweden FFQ measurements have good reproducibility and an estimated level of validity similar to that of FFQ measurements in other prospective cohort studies. The results from this study will form the basis for the correction of attenuation and regression dilution biases in relative risk estimates, in future studies relating FFQ measurements to disease outcomes.