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Activity Number:
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243
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Type:
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Contributed
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Date/Time:
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Tuesday, July 31, 2007 : 8:30 AM to 10:20 AM
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Sponsor:
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Biometrics Section
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| Abstract - #308783 |
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Title:
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Inference for Three-State Progressive Disease Models with Common Periodic Observations
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Author(s):
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Beth Ann Griffin*+ and Stephen Lagakos
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Companies:
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RAND Corporation and Harvard School of Public Health
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Address:
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1200 S Hayes Street, Arlington, VA, 22202,
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Keywords:
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Arm-in-cage experiments ; Progressive Disease models ; Interval censoring ; Time-to-event data
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Abstract:
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We develop statistical methods for designing and analyzing arm-in-cage experiments used to test the efficacy of insect repellents. Efficacy of a repellent can be described using a progressive three-state model in which the first two states represent varying degrees of protection (no landing and landing without biting) and the third state occurs once protection is completely lost (biting). In the experiments, subjects place their arms into cages periodically to observe whether mosquitoes land and/or bite. Since subjects within a treatment group follow the same cage visit schedule, transition times between states are interval censored into one of several fixed intervals. We develop an approach for estimating the parameters of interest when sojourn times are dependent and study design considerations for these experiments. The proposed methods are illustrated on real and simulated data.
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