Title | Two-step and likelihood methods for HIV viral dynamic models with covariate measurement errors and missing data |
Publication Type | Journal Article |
Year of Publication | 2012 |
Authors | Liu, W, WU, LANG |
Journal | Journal of Applied Statistics |
Volume | 39 |
Pagination | 963–978 |
Date Published | may |
ISSN | 0266-4763 |
Abstract | HIV viral dynamic models have received much attention in the literature. Long-term viral dynamics may be modelled by semiparametric nonlinear mixed-effect models, which incorporate large variation between subjects and autocorrelation within subjects and are flexible in modelling complex viral load trajectories. Time-dependent covariates may be introduced in the dynamic models to partially explain the between-individual variations. In the presence of measurement errors and missing data in time-dependent covariates, we show that the commonly used two-step method may give approximately unbiased estimates but may under-estimate standard errors. We propose a two-stage bootstrap method to adjust the standard errors in the two-step method and a likelihood method. |
URL | http://dx.doi.org/10.1080/02664763.2011.632404 |
DOI | 10.1080/02664763.2011.632404 |