Modeling lesion counts in multiple sclerosis when patients have been selected for baseline activity.

ABSTRACT: The number of new gadolinium-enhancing lesions discovered via magnetic resonance imaging is a well-established outcome for multiple sclerosis studies, especially Phase II Studies. Due to the high cost of magnetic resonance imaging scans, many investigators select participants for the presence of lesions. While this selection procedure is thought to improve the power of inferences, the effect of screening for baseline activity on parameter estimation and interval coverage has not yet been examined. The objective of this study was to investigate the performance of the negative binomial distribution for modeling lesion count data in multiple sclerosis when patients have been selected for activity on a baseline scan. We performed computer simulations to investigate the influence of the screeni

SUBMITTER: Morgan CJ 

PROVIDER: S-EPMC3352326 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature