{"classes":[{"categories":[{"measurements":[{"groupId":"OG000","value":"80.5"},{"groupId":"OG001","value":"85.9"}]}],"title":"Maximum QTcS <450 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"17.9"},{"groupId":"OG001","value":"11.8"}]}],"title":"Maximum QTcS 450-<480 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"1.1"},{"groupId":"OG001","value":"2.3"}]}],"title":"Maximum QTcS 480-<500 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"0.5"},{"groupId":"OG001","value":"0"}]}],"title":"Maximum QTcS >=500 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"85.9"},{"groupId":"OG001","value":"89.5"}]}],"title":"Maximum QTcF <450 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"12.2"},{"groupId":"OG001","value":"9.5"}]}],"title":"Maximum QTcF 450-<480 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"1.6"},{"groupId":"OG001","value":"0.9"}]}],"title":"Maximum QTcF 480-<500 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"0.2"},{"groupId":"OG001","value":"0"}]}],"title":"Maximum QTcF >=500 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"64.9"},{"groupId":"OG001","value":"69.1"}]}],"title":"Maximum QTcB <450 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"32.2"},{"groupId":"OG001","value":"27.3"}]}],"title":"Maximum QTcB 450-<480 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"2.3"},{"groupId":"OG001","value":"3.2"}]}],"title":"Maximum QTcB 480-<500 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"0.7"},{"groupId":"OG001","value":"0.5"}]}],"title":"Maximum QTcB >=500 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"92.7"},{"groupId":"OG001","value":"94.5"}]}],"title":"Maximum QTcS Change <30 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"6.6"},{"groupId":"OG001","value":"5.5"}]}],"title":"Maximum QTcS 30<=Change <60 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"0.7"},{"groupId":"OG001","value":"0"}]}],"title":"Maximum QTcS Change>=60 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"91.6"},{"groupId":"OG001","value":"93.6"}]}],"title":"Maximum QTcF Change <30 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"7.9"},{"groupId":"OG001","value":"6.4"}]}],"title":"Maximum QTcF 30<=Change <60 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"0.5"},{"groupId":"OG001","value":"0"}]}],"title":"Maximum QTcF Change>=60 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"88.9"},{"groupId":"OG001","value":"91.4"}]}],"title":"Maximum QTcB Change <30 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"10.2"},{"groupId":"OG001","value":"8.2"}]}],"title":"Maximum QTcB 30<=Change <60 msec"},{"categories":[{"measurements":[{"groupId":"OG000","value":"0.9"},{"groupId":"OG001","value":"0.5"}]}],"title":"Maximum QTcB Change>=60 msec"}],"denoms":[{"counts":[{"groupId":"OG000","value":"441"},{"groupId":"OG001","value":"220"}],"units":"Participants"}],"description":"Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and sent to a central laboratory for blinded manual adjudication. The average was calculated. The time corresponding to beginning of depolarization to repolarization of the ventricles (QT interval) was adjusted for RR interval using QT and RR from each ECG by Fridericia's formula (QTcF = QT divided by cube root of RR), by Bazette's formula (QTcB = QT divided by square root of RR) and corrected QT interval according to study-specific criteria (QTcS). Percentage of participants with post-baseline maximum absolute values and maximum increase from baseline were summarized for the safety analysis population.","groups":[{"description":"Participants received letrozole 2.5 milligram (mg) orally QD (once daily) combined with palbociclib 125 mg QD for 21 days of every-28-day cycle, followed by 7 days off treatment.","id":"OG000","title":"Palbociclib Plus Letrozole"},{"description":"Participants received letrozole 2.5 mg orally QD combined with placebo QD for 21 days of every-28-day cycle, followed by 7 days off treatment.","id":"OG001","title":"Placebo Plus Letrozole"}],"paramType":"NUMBER","populationDescription":"The AT population or safety analysis set included all participants who received at least 1 dose of study medication, with treatment assignments designated according to actual study treatment received.","reportingStatus":"POSTED","timeFrame":"For safety monitoring triplicate ECGs were obtained at 0 hour (pre-dose) on Day 1 of Cycle 1, Day 14 of Cycles 1 and Cycle 2, then on Day 1 of Cycles 4, 7, and 10 (ECGs beyond Cycle 10 were performed as clinically indicated)","title":"Percentage of Participants With Corrected QT Interval (QTc)","type":"SECONDARY","unitOfMeasure":"Percentage of participants"}