aids {JSM} | R Documentation |
ddI versus ddC in HIV-infected Patients
Description
A randomized clinical trial in which both survival and longitudinal data were collected to compare the efficacy and
safety of two antiretroviral drugs, namely ddI
(didanosine) and ddC
(zalcitabine), in treating HIV-infected patients intolerant or failing zidovudine (AZT) therapy.
Format
A data frame with 1405 observations on the following 12 variables.
ID
patient ID, there are 467 patients in total.
Time
survival time, i.e. time to death or censoring.
death
death indicator: 0 denotes censoring; 1 denotes death.
obstime
time points at which the longitudinal measurements, i.e. CD4 cell counts, are recorded.
CD4
CD4 cell counts measured at
obstime
.drug
drug indicator with two levels:
ddI
andddC
.gender
gender indicator with two levels:
male
andfemale
.prevDiag
AIDS diagnosis at study entry indicator with two levels:
AIDS
andnoAIDS
.AZT
AZT intolerance/failure indicator with two levels:
intolerance
andfailure
.start
same with
obstime
, starting time of the interval which contains the time of the CD4 cell count measurement.stop
ending time of the interval which contains the time of the CD4 cell count measurement.
event
event indicator suggesting whether the event-of-interest, i.e. death, happens in the interval given by
start
andstop
.
Source
Goldman, A., Carlin, B., Crane, L., Launer, C., Korvick, J., Deyton, L. and Abrams, D. (1996) Response of CD4+ and clinical consequences to treatment using ddI or ddC in patients with advanced HIV infection. Journal of Acquired Immune Deficiency Syndromes and Human Retrovirology 11, 161–169.
References
Guo, X. and Carlin, B. (2004) Separate and joint modeling of longitudinal and event time data using standard computer packages. The American Statistician 58, 16–24.
Xu, C., Baines, P. D. and Wang, J. L. (2014) Standard error estimation using the EM algorithm for the joint modeling of survival and longitudinal data. Biostatistics 15, 731–744
Examples
head(aids)