Time frame: For participants who began IT treatment in HGT-HIT-094: From Baseline of HGT-HIT-094 up to Month 61 in relation to HGT-HIT-094; For participants who began IT treatment in this study: From Baseline of this study up to Month 49 of this study.
DAS-II was used to assess all participants of age 2 years,6 months or older.DAS-II comprises 2 overlapping batteries.EYB was designed for children ages 2 years,6 months through 6 years,11 months.SAB was designed for children ages 7 years,0 months through 17 years,11 months.Core subtests include Verbal Comprehension,Picture Similarities,Naming Vocabulary,Pattern Construction,Matrices, & Copying for DAS-II Early Years&Recall of Designs,Word Definitions, Pattern Construction,Matrices,Verbal Similarities, & Sequential and Quantitative Reasoning for the DAS-II School Years. The DQ was computed as a ratio and expressed as a percentage using the AES divided by the age at testing ([AES/chronological age] × 100; range, 0-100). The higher score indicates greater cognitive ability. The subtest score represent a score (mean = 50 and standard deviation of 10) on which higher scores indicate a higher level of cognitive ability. A positive change value indicates improvement in cognitive ability.