to.balanced: Transform data to the longitudinal balanced format

Description

Transforms a longitudinal data set in the unbalanced format to the balanced format.

Usage

to.balanced(data, id.col, time.col, Y.col, other.col = NA)

Value

A data frame with longitudinal data in the balanced format. The balanced format is considered in this context as the format where each row has data on each subject. Notice that in this format we will have multiple columns for the same longitudinal variable, each corresponding to the variable observed at each time point.

Arguments

data: a data frame with longitudinal data in the unbalanced format. That is, in the format of 'one row per observation'.
id.col: a column number, or column name, in the data frame data, where the patient identifier is located.
time.col: a column number, or column name, in the data frame data, where the time measurements are.
Y.col: a vector of column numbers, or column names, of longitudinal variables, and/or time dependent covariates in the data frame data.
other.col: a vector of column numbers, or column names, of baseline covariates, and/or other subject level data, as for example, survival data. Default does not include other.col.

Author

Ines Sousa

Examples

Run this code

simul <- data.frame(num = 1:10,
                    Y1.1 = rnorm(10), Y1.2 = rnorm(10),
                    Y2.1 = rnorm(10), Y2.2 = rnorm(10),
                    age = rnorm(10))
simul <- to.unbalanced(simul, id.col = 1, times = c(1, 2), 
                       Y.col = 2:5, other.col = 6)
simul <- to.balanced(simul, id.col = "num", time.col = "time",
                     Y.col = c("Y1.1", "Y2.1"), other.col = "age")