Skip to contents

Creating Objects of Kaplan-Meier Curve

Source: R/km_.R
km_.Rd

km_ is a wrapper function creating an object of Kaplan-Meier curve to be passed into jointCovariance, the main function of this package through its argument .... The object defines how a Kaplan-Meier curve would be fitted.

Usage

km_(formula, times = NULL, conf_type, data_index = 1)

Arguments

formula

a formula created by survival::Surv().

times

numeric vector of time. Survival probabilities at times are computed (with g-transformation defined by conf_type).

conf_type

character. Type of confidence interval. It must be one of "log", "log-log", "plain", "logit", or "arcsin".

data_index

integer. Index of the data frame in the data argument of jointCovariance to be used when fitting a generalized linear model.

Details

Usually, g-transformation is applied to the survival probability S(t) to obtain pointwise confidence interval of a Kaplan-Meier curve. This can be achieved by specifying conf_type. For identity transformation, use conf_type = "plain".

This function can only be used with jointCovariance when the bootstrap method is used to estimate variance-covariance matrix of multiple outcome models.