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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 - #308960 |
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Title:
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Sample-Size Calculations in Case-Control Unmatched Studies When Controls Contain Cases
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Author(s):
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Xiaolei Liu*+ and Marepalli B. Rao
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Companies:
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University of Cincinnati and University of Cincinnati
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Address:
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Environmental Health Dept, Cincinnati, OH, 45220,
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Keywords:
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Case-control ; Misclassification ; Sample size ; Sleep Apnea ; Contingency table
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Abstract:
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In this paper, the focus is on 2×2 case-control unmatched studies, in which the cases (those with the disease) are genuine but the controls may contain patients with disease due to misclassification in disease screening. We systemically examine the effect of such contamination on odds ratio and data analysis. We will provide sample size formulas using two different procedures by taking into account the contamination ratio, one procedure is by testing equivalence of two sample proportions and the other using log odds ratio test. The misclassification problem arose when planning a study to identify factors causing sleep apnea.
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