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Activity Number:
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172
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Type:
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Contributed
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Date/Time:
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Monday, August 3, 2009 : 10:30 AM to 12:20 PM
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Sponsor:
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Biopharmaceutical Section
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| Abstract - #305299 |
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Title:
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Comparison of Right and Interval Censoring Methods in Analysis of Time to Progression in Presence of Asymmetry and Missed Assessments
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Author(s):
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Somesh Chattopadhyay*+ and Shenghui Tang and Rajeshwari Sridhara
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Companies:
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FDA and FDA and FDA
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Address:
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10903 New Hampshire Avenue, Silver Spring, MD, 20993,
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Keywords:
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disease progression ; asymmetry ; missing data ; interval censoring ; right censoring
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Abstract:
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Time to progression (TTP), defined as time from randomization to disease progression (PD) and progression free survival (PFS) defined as the time from randomization to PD or death, are two important endpoints in evaluating efficacy of cancer drug products. PD is measured using pre-defined criteria at scheduled visits. The frequency and length of schedule visits are designed based on clinical practices and the natural history of disease. Some problems with TTP and PFS are missed PD assessments and asymmetry in PD assessments between treatment arms. In this research, through simulations, we compare right-censoring and interval-censoring methods in terms of bias in estimation and Type I error rate and power in hypothesis testing when asymmetry in PD assessments between treatment arms and missed assessments are present. The simulations will also account for variation of assessment times.
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