Random effects meta-analysis of napping cessation by age groupings. Individual studies are ordered by proportion napping and then median age of sample range within each age grouping. Age = median of age range (months), non = number children not napping, n = number children, I2 = 0–100 indictor of heterogeneity between studies (only for random effect rows), p = p-value for I2 and if less than 0.05 means significant heterogeneity (only for random effect rows), and W = weighting in random effects analysis.