Data Analysis To analyze neuropsychological measures for which no stan dardization data were available (ie, CHIPASAT and CNT), mea scores were calculated for 3 chronological age bands: 6 to 9 years10 to 12 years, and 13 to 15 years, based on control participants performance. Because some of the data were not normally distrib-
uted, nonparametric univariate analysis (Mann Whitney U) was used for univariate comparisons. 2 analysis was used for analyses involving categorical variables. Kruskal Wallis analysis was used when comparing more than 2 groups on 1 variable. An alpha level