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Activity Number:
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292
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Type:
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Contributed
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Date/Time:
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Tuesday, July 31, 2007 : 10:30 AM to 12:20 PM
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Sponsor:
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Section on Statistics in Epidemiology
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| Abstract - #309959 |
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Title:
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A Latent Group Approach for Combining Matched and Unmatched Case-Control Studies
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Author(s):
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Mulugeta Gebregziabher*+ and Paulo Guimaraes and Wendy Cozen and David Conti
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Companies:
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MUSC and MUSC and University of California, Los Angeles and University of Southern California
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Address:
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135 Cannon St suite 303, Charleston, SC, 29425,
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Keywords:
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case-control ; conditional likelihood ; latent group ; polytomous conditional likelihood
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Abstract:
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In case-control studies, it is common practice to compare two or more different sets of controls with the same case group to validate or confirm a positive or negative finding. This usually involves fitting separate models for each case-control comparison, testing the homogeneity of the parameters and if appropriate obtaining a pooled estimate. But, fitting separate models tends to lead to a homogeneity test with inflated type-II-error rate and to a pooled estimate with larger standard error. The problem is compounded when one control group is matched and the other is unmatched. The alternative to fitting separate models is to use a multinomial model. However, available methods for combining matched and unmatched case-control data do not handle multinomial response. We propose a unified latent group approach that can be used for both binary and multinomial response case-control data.
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