2.6. Sample Size Consideration
MP
This was based on the primary outcome of the main trial (height and knee-heel length) where detecting 0.35 SD or a greater difference in any outcome between any of the two groups, at 5% significance level and 80% power, while allowing for 10% attrition, allowed us to recruit 150 children per group (600 in total based on the 4 combinations of MP and WP). If there were no interactions between the two experimental arms, then two groups of 300 children could be compared enabling differences of 0.24 SD to be detected.