leuk: Survival Times and White Blood Counts for Leukaemia Patients
In SMPracticals: Practicals for Use with Davison (2003) Statistical Models

leuk	R Documentation

Survival Times and White Blood Counts for Leukaemia Patients

Description

A data frame of data from 33 leukaemia patients.

Usage

data(leuk)

Format

A data frame with 33 observations on the following 3 variables.

wbc: white blood cell count
ag: a test result, '"present"' or '"absent"'
time: survival time in weeks

Details

Survival times are given for 33 patients who died from acute myelogenous leukaemia. Also measured was the patient's white blood cell count at the time of diagnosis. The patients were also factored into 2 groups according to the presence or absence of a morphologic characteristic of white blood cells. Patients termed AG positive were identified by the presence of Auer rods and/or significant granulation of the leukaemic cells in the bone marrow at the time of diagnosis.

Source

Feigl, P. and Zelen, M. (1965) Estimation of exponential survival probabilities with concomitant information. Biometrics, 21, 826–838.

References

Cox, D. R. and Oakes, D. (1984) Analysis of Survival Data. Chapman & Hall, p. 9.

Davison, A. C. (2003) Statistical Models. Cambridge University Press. Page 542.

Examples

data(leuk)
library(survival)
plot(survfit(Surv(time) ~ ag, data = leuk), lty = 2:3, col = 2:3)
# fit of exponential model
summary(glm(time~ag+log10(wbc),data=leuk,family=Gamma(log)),dispersion=1)
# now Cox models
leuk.cox <- coxph(Surv(time) ~ ag + log(wbc), leuk)
summary(leuk.cox)

SMPracticals documentation built on May 29, 2024, 12:19 p.m.