Format
A data frame with 1200 observations on the following 9 variables.
id- an ordered factor giving a unique identifier for the subject in the study.
gender- a numeric vector giving the gender.
height- a numeric vector giving the height for age as a percentage
of the National Center for Health Statitics standard
centered at 90.
cosv- a numeric vector giving the seasonal cosine for the annual cycle.
sinv- a numeric vector giving the seasonal sine for the annual cycle.
xero- a numeric vector giving the presence (1) or absence (0) of
xeropthalmia.
baseage- a numeric vector giving the age at the entry.
age- a numeric vector giving the age of the child in months centered at 36
infect- a numeric vector giving the presence (1) or absence (0) of
respiratory infection.
Source
Sommer, A., Katz, J., and Tarwotjo, I. (1984) Increased risk of respiratory infection and
diarrhea in children with pre-existing mild vitamin A deficiency, American Journal
of Clinical Nutrition, 40: 1090-1095.