The efficacy of antiretroviral therapies for human immunodeficiency virus (HIV) infection can be assessed by studying the trajectory of the changing viral load with treatment time, but estimation of viral trajectory parameters by using the implicit function form of linear and nonlinear parametric models can be problematic. Using longitudinal viral load data from a clinical study of HIV-infected patients in Taiwan, we described the viral trajectories by applying a nonparametric mixed-effects model. We were then able to compare the efficacies of highly active antiretroviral therapy (HAART) and conventional therapy by using Young and Bowman’s (1995) test.
Li, Chin-Shang; Liang, Hua; Hsieh, Ying-Hen; and Twu, Shiing-Jer
"Comparison Of Viral Trajectories In Aids Studies By Using Nonparametric Mixed-Effects Models,"
Journal of Modern Applied Statistical Methods: Vol. 2
, Article 17.
Available at: http://digitalcommons.wayne.edu/jmasm/vol2/iss2/17