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Change in mean BMI Z-score in girls (95% CI) relative to baseline in intervention and control schools according to age and period of study. Period 1 (March 03–Nov 03), Period 2 (Nov 03–March 04), Period 3 (March 04–Nov 04). Proc Mixed and Tukey test to compare intervention and control groups and time effects. Adapted from Reference 10 with permission.
