Within-subject exposure dependency in case-crossover studies.

S K Vines; C P Farrington

doi:10.1002/sim.960

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Within-subject exposure dependency in case-crossover studies.

S K Vines·C P Farrington

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Abstract

In the case-crossover design, only cases are sampled and the hazard ratio is estimated from within-subject comparisons of exposures at the event time and in M control periods prior to the event. We consider the effect of within-subject dependence of exposures in successive time periods. We show that estimates obtained from the conditional logistic model are biased. This bias disappears if the distribution of exposures in the M+1 successive time intervals is exchangeable. In contrast, the Mantel-Haenszel estimator for the odds ratio is approximately unbiased provided that exposures are stationary. Suitable methods of analysis of case-crossover designs using maximum likelihood may be derived from cohort rather than case-control models.

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Bias Case-Control Studies Cross-Over Studies Humans Likelihood Functions Logistic Models Journal Article

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S K Vines, C P Farrington. 2001-10-30. Within-subject exposure dependency in case-crossover studies.. https://doi.org/10.1002/sim.960

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