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Example script

run_example.Rmd

Load data 

rm(list = ls())
library(modelLong)

# Load example longitudinal data (must be of long format)
URL <- "https://raw.githubusercontent.com/alejandroh3005/longitudinal-data/main/data/cdc-birthwt.csv"
data <- read.csv(URL)
# Define binary group variable
data$"Low weight" <- as.factor(ifelse(data$bweight < 1200, 1, 0))

Summarize data

Print Table 1.

# Summarize data in Table 1, stratify summary by low weight status
# Exclude Mother and Child ID in data summary
summary_res <- modelLong::summary(data = data[-c(1, 5)],
                                  group_var = "Low weight")
summary_res$table1
Variable Overall, N = 4,3901 Low weight
0, N = 4,3601 1, N = 301
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    1 878 (20%) 870 (20%) 8 (27%)
    2 878 (20%) 874 (20%) 4 (13%)
    3 878 (20%) 873 (20%) 5 (17%)
    4 878 (20%) 870 (20%) 8 (27%)
    5 878 (20%) 873 (20%) 5 (17%)
bweight 3,156 (2,850, 3,515) 3,172 (2,863, 3,515) 854 (680, 1,087)
mage 22 (18, 24) 22 (18, 24) 21 (18, 24)
1 n (%); Mean (IQR)

Plot data

Plot repeated measures over time and ACF

# Create plots of repeated measures and ACF
plot_res <- modelLong::plot(data = data,
                            outcome = "bweight",
                            time = "mage",
                            id = "mid",
                            col_group = "Low weight")
plot_res$data_plot

plot_res$acf_plot