{"groups":[{"description":"2.5 mg by mouth (p.o.) once daily","id":"FG000","title":"Letrozole"},{"description":"1 mg p.o. once daily","id":"FG001","title":"Anastrozole"}],"periods":[{"dropWithdraws":[{"reasons":[{"groupId":"FG000","numSubjects":"71"},{"groupId":"FG001","numSubjects":"79"}],"type":"Withdrawal by Subject"},{"reasons":[{"groupId":"FG000","numSubjects":"35"},{"groupId":"FG001","numSubjects":"30"}],"type":"Protocol Violation"},{"reasons":[{"groupId":"FG000","numSubjects":"28"},{"groupId":"FG001","numSubjects":"35"}],"type":"Lost to Follow-up"},{"reasons":[{"groupId":"FG000","numSubjects":"196"},{"groupId":"FG001","numSubjects":"216"}],"type":"Disease progression"},{"reasons":[{"groupId":"FG000","numSubjects":"28"},{"groupId":"FG001","numSubjects":"47"}],"type":"Death"},{"reasons":[{"groupId":"FG000","numSubjects":"311"},{"groupId":"FG001","numSubjects":"296"}],"type":"Adverse Event"},{"reasons":[{"groupId":"FG000","numSubjects":"22"},{"groupId":"FG001","numSubjects":"25"}],"type":"Administrative problems"},{"reasons":[{"groupId":"FG000","numSubjects":"49"},{"groupId":"FG001","numSubjects":"61"}],"type":"Abnormal test procedure(s) result"},{"reasons":[{"groupId":"FG000","numSubjects":"4"},{"groupId":"FG001","numSubjects":"0"}],"type":"Abnormal laboratory values"},{"reasons":[{"groupId":"FG000","numSubjects":"17"},{"groupId":"FG001","numSubjects":"19"}],"type":"Protocol deviation"}],"milestones":[{"achievements":[{"groupId":"FG000","numSubjects":"2078"},{"groupId":"FG001","numSubjects":"2094"}],"type":"STARTED"},{"achievements":[{"groupId":"FG000","numSubjects":"2061"},{"groupId":"FG001","numSubjects":"2075"}],"type":"Intent-to-treat (ITT)"},{"achievements":[{"groupId":"FG000","numSubjects":"2049"},{"groupId":"FG001","numSubjects":"2062"}],"type":"Safety Set"},{"achievements":[{"groupId":"FG000","numSubjects":"1317"},{"groupId":"FG001","numSubjects":"1286"}],"type":"COMPLETED"},{"achievements":[{"groupId":"FG000","numSubjects":"761"},{"groupId":"FG001","numSubjects":"808"}],"type":"NOT COMPLETED"}],"title":"Overall Study"}],"recruitmentDetails":"Participants, who had recently undergone surgery, were randomly assigned in 1:1 ratio to letrozole or anastrozole. Participants received daily treatment until disease recurrence/relapse or for a maximum of 5 years. Participants underwent post-treatment long term follow-up for disease-free survival and overall survival."}