A case-control study of smoking and Alzheimer's disease.
Usage
alzheimer
Format
A data frame with 538 observations on 3 variables.
smoking
a factor with levels "None", "<10", "10-20" and
">20" (cigarettes per day).
disease
a factor with levels "Alzheimer", "Other dementias" and
"Other diagnoses".
gender
a factor with levels "Female" and "Male".
Details
Subjects with Alzheimer's disease are compared to two different control groups
with respect to smoking history. The data are given in Salib and Hillier
(1997, Tab. 4).
Source
Salib, E. and Hillier, V. (1997). A case-control study of smoking and
Alzheimer's disease. International Journal of Geriatric Psychiatry12(3), 295–300.
References
Hothorn, T., Hornik, K., van de Wiel, M. A. and Zeileis, A. (2006). A Lego
system for conditional inference. The American Statistician60(3), 257–263.
Examples
## Spineplots
op <- par(no.readonly = TRUE) # save current settings
layout(matrix(1:2, ncol = 2))
spineplot(disease ~ smoking, data = alzheimer,
subset = gender == "Male", main = "Male")
spineplot(disease ~ smoking, data = alzheimer,
subset = gender == "Female", main = "Female")
par(op) # reset
## Asymptotic Cochran-Mantel-Haenszel test
cmh_test(disease ~ smoking | gender, data = alzheimer)