A latent normal distribution model for analysing ordinal responses with applications in meta-analysis.
We consider the comparison of two treatments (or a treatment and a control/placebo) with responses that are classified into ordinal categories. By operating on the assumption that the responses are manifestations of some underlying continuous variables and that the definitions of the categories for the treatment group and the placebo group are the same in the same clinical test centre, we develop a model to examine the possible treatment effects. These treatment effects can be identified as location effect or dispersion effect. The method can be generalized to analyse clinical test results coming from different centres, where each centre may have its own standard in classifying responses. The method is technically undemanding and can be implemented in a very simple and straightforward way by using easily accessible software that can be downloaded at no cost. Real data sets are analysed for illustration.
Poon
Wai-Yin
WY
Department of Statistics, The Chinese University of Hong Kong, Shatin, Hong Kong. wypoon@cuhk.edu.hk
D000544:Alzheimer Disease / Q000188:drug therapy; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000009:adverse effects / Q000627:therapeutic use; D000897:Anti-Ulcer Agents / Q000494:pharmacology; D001168:Arthritis / Q000188:drug therapy; D002800:Cholinesterase Inhibitors / Q000627:therapeutic use; D003627:Data Interpretation, Statistical; D005767:Gastrointestinal Diseases / Q000139:chemically induced; D006801:Humans; D015201:Meta-Analysis as Topic; D016595:Misoprostol / Q000494:pharmacology; D008954:Models, Biological; D015233:Models, Statistical; D015337:Multicenter Studies as Topic / Q000379:methods; D016032:Randomized Controlled Trials as Topic / Q000379:methods*; D013619:Tacrine / Q000627:therapeutic use
D000894:Anti-Inflammatory Agents, Non-Steroidal; D000897:Anti-Ulcer Agents; D002800:Cholinesterase Inhibitors; D016595:Misoprostol; D013619:Tacrine