Related Experiment Video
Updated: Aug 24, 2026

A Computerized Test Battery to Study Pharmacodynamic Effects on the Central Nervous System of Cholinergic Drugs in Early Phase Drug Development
Published on: February 11, 2019
Test of treatment effect in pre-drug and post-drug count data with zero-inflation
Sudhir R Paul1, Xing Jiang, Shesh Nath Rai
1Department of Mathematics and Statistics, University of Windsor, 401 Sunset, Windsor, Ontario, Canada N9B 3P4. smjp@uwindosr.ca
Abstract:
A procedure for testing for treatment effect in data similar to the data on premature ventricular contractions (PVC) is presented. We consider a zero-inflated beta-binomial model. Based on this model, we develop score tests to test for treatment effect in the data in which observations in the form of counts are recorded before and after applying a therapy. Results of a small simulation experiment, to study small sample behaviour of a score test and a likelihood ratio test, are reported and the PVC data are analysed. Both the score and the likelihood ratio tests show good level properties. Either the score tests or the likelihood ratio tests can be used for testing the presence of treatment effect. The score tests, however, may be preferable because they use estimates of the parameters only under the null hypothesis and in the important range pi<0.5 power of the score test statistic S1 is slightly better than the likelihood ratio statistic LR1.
Related Concept Videos
Comparing Experimental Results: Student's t-Test
Time Course of Drug Effect
Wilcoxon Signed-Ranks Test for Matched Pairs
Sign Test for Matched Pairs
To conduct the sign test, we first calculate the differences in value between...
Bioequivalence Data: Statistical Interpretation
Cochran's Q Test
