The Biplot as a diagnostic tool of local dependence in latent class models. A medical application
Article first published online: 11 FEB 2008
Copyright © 2008 John Wiley & Sons, Ltd.
Statistics in Medicine
Volume 27, Issue 11, pages 1855–1869, 20 May 2008
How to Cite
Sepúlveda, R., Vicente-Villardón, J. L. and Galindo, M. P. (2008), The Biplot as a diagnostic tool of local dependence in latent class models. A medical application. Statist. Med., 27: 1855–1869. doi: 10.1002/sim.3194
- Issue published online: 10 APR 2008
- Article first published online: 11 FEB 2008
- Manuscript Accepted: 15 NOV 2007
- Manuscript Received: 24 JUL 2007
- latent class models;
- gold standard;
- local dependence;
- generalized linear model
Latent class models (LCMs) can be used to assess diagnostic test performance when no reference test (a gold standard) is available, considering two latent classes representing disease or non-disease status. One of the basic assumptions in such models is that of local or conditional independence: all indicator variables (tests) are statistically independent within each latent class. However, in practice this assumption is often violated; hence, the two-LCM fits the data poorly. In this paper, we propose the use of Biplot methods to identify the conditional dependence between pairs of manifest variables within each latent class. Additionally, we propose incorporating such dependence in the corresponding latent class using the log-linear formulation of the model. Copyright © 2008 John Wiley & Sons, Ltd.