# Interval-censored data for times to cytomegalovirus (CMV) shedding in blood and urine

### Description

The `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.

### Usage

1 |

### Format

A data frame with 204 observations on the following 6 variables.

`patient`

patient id

`lb`

left end point of an censoring interval for time to CMV shedding in blood

`rb`

right end point of an censoring interval for time to CMV shedding in blood

`lu`

left end point of an censoring interval for time to CMV shedding in urine

`ru`

right end point of an censoring interval for time to CMV shedding in urine

`cd4ind`

group indicator if patient's baseline CD4 count is below 75 (1 for below 75 and 0 otherwise)

### Details

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.

### Source

J. Sun (2006), "The Statistical Analysis of Interval-censored Failure Time Data", Springer.

### References

W. B. Goggins and D. M. Finkelstein (2000), "A proportional hazards model for multivariate interval-censored failure time data", Biometrics, 56: 940-943.