cmv data frame is based on an AIDS clinic trial on HIV-infected individuals. The data involve 204 patients who are classified into two groups based on whether patient's CD4 count is below 75 cells per μ l or not. Among the 204 patients, 111 of them had a CD4 count below 75.
A data frame with 204 observations on the following 6 variables.
left end point of an censoring interval for time to CMV shedding in blood
right end point of an censoring interval for time to CMV shedding in blood
left end point of an censoring interval for time to CMV shedding in urine
right end point of an censoring interval for time to CMV shedding in urine
group indicator if patient's baseline CD4 count is below 75 (1 for below 75 and 0 otherwise)
The survival times are time to the presence of CMV in blood and ullrine, respectively. The censoring intervals are in the format of (l_b, r_b] and (l_u, r_u]. For CMV in blood, there are 7 left-censored, 23 interval-censored, and 174 right-censored, but no exact observations. For CMV in urine, there are 49 left-censored, 67 interval-censored, and 88 right-censored, but no exact observations.
J. Sun (2006), "The Statistical Analysis of Interval-censored Failure Time Data", Springer.
W. B. Goggins and D. M. Finkelstein (2000), "A proportional hazards model for multivariate interval-censored failure time data", Biometrics, 56: 940-943.