Fig. 1

Box-and-whisker plot representing the median (line within the box), the interquartile range (length of the box), the 90th and the 10th percentiles (whiskers above and below the box) of Children’s Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND, a), intellectual abilities (RCPM, b), quality of speech (ALSSS, c), and language comprehension (TCGB, d) in children whose age was < 5 years (grey); ≥ 5 and < 10 years (orange); and ≥ 10 years (black). The horizontal short-dashed lines indicate the different levels of intellectual abilities, quality of speech, and language comprehension