a numeric vector. Age of the patient at the start of the trial.
cd4
a numeric vector. CD4 percentage at the current visit.
cd4.prev
a numeric vector. CD4 level at the preceding visit.
precd4
a numeric vector. Post-infection CD4 percentage.
lt
a numeric vector. Gives the starting time for the
time-intervals.
rt
a numeric vector. Gives the stopping time for the
time-interval.
Source
MACS Public Use Data Set Release PO4 (1984-1991). See reference.
References
Kaslow et al. (1987), The multicenter AIDS cohort study: rational,
organisation and selected characteristics of the participants.
Am. J. Epidemiology 126, 310–318.