cd4: Sample Data from "Applied Longitudinal Analysis"

In JohnHendrickx/Perturb: Tools for Evaluating Collinearity

Description

Sample data from Chapter 8 of "Applied Longitudinal Analysis" by Garrett Fitzmaurice, Nan Laird & James Ware. The data are from the "ACTG Study 193A". This was a randomised, double-blind study of 1309 AIDS patients where subjects with dual combinations of HIV-1 inhibitors were compared to subjects with triple combinations of HIV-1 reverse transciptase inhibitors. The dependent variable in the dataset is logcd4, calculated as the log of the CD4 counts plus 1. The CD4 counts were assessed at baseline and between 1 and 9 times during the 40 weeks follow-up. The timing of assessments relative to baseline is measured in weeks.

Usage

data(cd4)

Format

A data frame containing the following 6 variables.

id

Subject id

group

Treatment Group

age

Age at baseline (years)

sex

Sex (1=male, 0=female)

trt

Treatment (1=Triple therapy, 0=Dual therapy)

week

Time since baseline (weeks)

week_16

Time since week 16 (max of 0, week - 16)

w16

week_16 - week

logcd4

log CD4 count plus 1

Source

https://content.sph.harvard.edu/fitzmaur/ala2e/

References

Garrett Fitzmaurice, Nan Laird & James Ware. (2004). Applied Longitudinal Analysis. New York: John Wiley & Sons.

Examples

data(cd4)

JohnHendrickx/Perturb documentation built on Nov. 27, 2021, 11:19 p.m.