Estimating odds ratios adjusting for misclassification in Alzheimer's disease risk factor assessment.
Epidemiological studies of Alzheimer's disease and dementia are often two-phase studies including a screening phase and a clinical assessment phase. It is common to interview a relative of the subject at each of these phases to obtain information about the subject's exposure to risk factors. This can result in a misclassification error when assessing risk factors, as the two responses of the relative often differ. This is especially a problem for risk factors involving life-style and family history which cannot be confirmed using the subject's medical records. A naive analysis using data from each phase separately would give two different estimates of the odds ratio; both estimates could be biased. In this paper, we extend the estimation methods adjusting for misclassification developed by Liu and Liang to data collected through two-phase sampling. We first use a latent class analysis and the EM algorithm to estimate the misclassification parameters. We then derive the maximum pseudo-likelihood estimators, conditional on the misclassification parameters, to estimate the odds ratios accounting for the complex sampling study design. We propose to use the jack-knife estimator for estimation of the variances. We apply the above method to data collected in the Indianapolis-Ibadan Dementia Study to estimate the odds ratio for smoking adjusting for misclassification error.
Emsley
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CL
Division of Biostatistics, Indiana University School of Medicine, RG/4th, 1001 West Tenth Street, Indianapolis, IN 46202-2859, USA. clemsley@iupui.edu
Gao
S
S
Hall
K S
KS
Hendrie
H C
HC
D001741:Black or African American / Q000706:statistics & numerical data; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000145:classification / Q000175:diagnosis / Q000453:epidemiology*; D015982:Bias; D044383:Black People; D015984:Causality; D003431:Cross-Cultural Comparison; D005260:Female; D006801:Humans; D007196:Indiana / Q000453:epidemiology; D016013:Likelihood Functions; D008297:Male; D009483:Neuropsychological Tests / Q000706:statistics & numerical data*; D009549:Nigeria / Q000453:epidemiology; D016017:Odds Ratio; D012307:Risk Factors; D012494:Sampling Studies