Randomization and Masking
Children were randomized to the order in which they underwent sleep restriction and sleep extension weeks and were stratified by age group (8-10 years or 11-12 years) and sex (male or female). Randomization to order was generated by one of us (J.J.H., the study biostatistician) using random block lengths in Stata, version 17.0 (StataCorp LLC) in a 1:1 allocation and then was uploaded to a research management program randomization module (REDCap; Vanderbilt University).