Fig. 1

Flow chart of the systematic review process. * Grijalva-Eternod et al. [16] and Anderson et al. [17] reported on the same study population. Anderson et al. described differences in body composition between boys and girls, their report was therefore used for the evaluation of the association between gender and body composition Lee et al. [18] and Lampl et al. [19] also reported on the same study population, Lampl et al. reported in more detail on the ethnicity of the study population, their report was therefore used for the evaluation of the association of ethnicity and body composition.