Creates an object of class 'jointdata'

Description

This function creates an object of class jointdata. This is an object with information on at least one of, longitudinal data or survival data. Moreover, it can also have data on baseline covariates.

Usage

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jointdata(longitudinal = NA, survival = NA, baseline = NA,
       id.col = "ID", time.col = NA)

Arguments

longitudinal

a data frame or matrix in the unbalanced format (one row per observation), with subject identification, time of measurements, and longitudinal measurements and/or time dependent covariates. This must be given if no survival argument is.

survival

a data frame or matrix with survival data for all the subjects. This must be given if no longitudinal argument is.

baseline

a data frame or matrix with baseline covariates, or non-time dependent covariates, for the same subjects as in survival and/or longitudinal. This has to be in the balanced format (one row per subject). By default an object of this class does not include baseline covariates.

id.col

an element of class character with the name identification of subject. This is to identify the subject identification in the data frames.

time.col

an element of class character with the time measurements identification. This is to identify the time column in the data frames.

Details

This function creates an object of class jointdata. This is a list with elements used in joint modelling, mainly longitudinal and/or survival data. The output has to have at least one of the data sets, longitudinal or survival. However, for joint modelling is necessary to have both data sets. Moreover, a third data frame is possible to be given as input, for the baseline (non-time dependent) covariates. The subject identification and time measurement column names are necessary.

Value

This function returns a list of length six. The first element is the vector of subjects identification. The second is, if exists a data frame of the longitudinal data. The third element of the list is, if exists a data frame of the survival data. The fourth element of the list is, if exists a data frame on the baseline covariates. The fifth is, if longitudinal data is given, the column name identification of longitudinal times. And the sixth and last element of the list is the column name identification of subjects.

Author(s)

Ines Sousa (isousa@math.uminho.pt)

Examples

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data(heart.valve)
heart.surv <- UniqueVariables(heart.valve,
                              var.col = c("fuyrs", "status"), 
                              id.col = "num")
heart.valve.jd <- jointdata(survival = heart.surv, 
                            id.col = "num",
                            time.col = "time")