Statistical analyses
headache, child-
The child- and headache characteristics are described by absolute and relative frequencies and means with 10th and 90th percentiles for all children and stratified by headache type. The statistical significance of differences between the three groups were assessed using the Kruskal Wallis test for continuous and ordinal variables, and an extension of Fisher’s exact test for binary and categorical variables. Kernel density estimates were used to depict distributional differences in continuous variables between subgroups of children.