Fig. 2

Surgical procedures in the overall population. (a) Percentage of patients in the overall population undergoing surgical procedures at any time (N = 61). (b) Median age at first surgical procedure for surgeries performed in the overall population. The overall population contains both prospective and retrospective patients. In part (b), diamonds indicate the median age of onset (years) and bars indicate the 10th and 90th percentiles. ‘Other’ is a category in the database in which surgical procedures not covered by the main database fields may be recorded using free text; this category included, but was not limited to, heel cord lengthening and pacemaker implantation. In some cases, a surgical procedure recorded using free text was considered to fall under a main database category; in these instances, surgical procedures originally listed as ‘Other’ were reclassified into the appropriate main category and the reclassification was verified by the HOS Biostatistician and the HOS Medical Monitor. CVAD, central venous access device; IS, intracranial shunt; PEG, percutaneous endoscopic gastrostomy