{"groups":[{"description":"Participants assigned to the average-risk arm had localized tumor without overt evidence of invasion beyond the posterior fossa (or supratentorial compartment for PNET's/ATRT). Participants with T4 disease met the following criteria: gross total resection defined as residual tumor or imaging abnormality whose size was \\<1.5 cm\\^2 on postoperative CT or MR images, no evidence of CNS or extraneural metastasis, and brain stem invasion by the tumor in the absence of imaging evidence of residual tumor (tumor size \\<1.5 cm\\^2).","id":"FG000","title":"Average-Risk Group"},{"description":"Participants assigned to the high-risk arm were determined to have the presence of metastatic disease within the neuraxis (i.e., evidence of subarachnoid dissemination), OR presence of residual disease (≥1.5 cm\\^2) at the primary site after surgery.","id":"FG001","title":"High-Risk Group"}],"periods":[{"dropWithdraws":[{"reasons":[{"groupId":"FG000","numSubjects":"2"},{"groupId":"FG001","numSubjects":"0"}],"type":"Still on therapy"},{"reasons":[{"groupId":"FG000","numSubjects":"0"},{"groupId":"FG001","numSubjects":"1"}],"type":"Bone involvement confirmed by bone scan"},{"reasons":[{"groupId":"FG000","numSubjects":"6"},{"groupId":"FG001","numSubjects":"5"}],"type":"Excessive toxicity"},{"reasons":[{"groupId":"FG000","numSubjects":"3"},{"groupId":"FG001","numSubjects":"5"}],"type":"Non-specified"},{"reasons":[{"groupId":"FG000","numSubjects":"2"},{"groupId":"FG001","numSubjects":"1"}],"type":"Withdrawal by Subject"},{"reasons":[{"groupId":"FG000","numSubjects":"4"},{"groupId":"FG001","numSubjects":"1"}],"type":"Physician Decision"},{"reasons":[{"groupId":"FG000","numSubjects":"1"},{"groupId":"FG001","numSubjects":"11"}],"type":"Progressive disease"}],"milestones":[{"achievements":[{"groupId":"FG000","numSubjects":"269"},{"groupId":"FG001","numSubjects":"144"}],"type":"STARTED"},{"achievements":[{"groupId":"FG000","numSubjects":"251"},{"groupId":"FG001","numSubjects":"120"}],"type":"COMPLETED"},{"achievements":[{"groupId":"FG000","numSubjects":"18"},{"groupId":"FG001","numSubjects":"24"}],"type":"NOT COMPLETED"}],"title":"Overall Study"}],"preAssignmentDetails":"Of the 416 participants enrolled, three were ineligible and taken off study.","recruitmentDetails":"416 participants were enrolled between 9/9/2003 and 3/7/2013."}