zinc {NestedCohort} | R Documentation |
zinc
is a data frame, with some variables observed on all
subjects, and some variables not. The outcome variable is ec01,
indicating esophageal cancer or not at time futime01. The zinc
variables are in zncent (continuous), znqt (ordinal zinc quartiles),
or znquartiles (factor variable notating quartiles of zinc)
data(zinc)
See nested.coxph for example of using this dataset.
Steven D. Mark
Christian C. Abnet, Barry Lai, You-Lin Qiao, Stefan Vogt, Xian-Mao Luo, Philip R. Taylor, Zhi-Wei Dong, Steven D. Mark, Sanford M. Dawsey. Zinc concentration in esophageal biopsies measured by X-ray fluorescence and cancer risk. Journal of the National Cancer Institute, 2005; 97(4) 301-306