Becher H
Institute of Epidemiology and Biometry, German Cancer Research Center, Heidelberg.
Stat Med. 1991 Mar;10(3):375-82. doi: 10.1002/sim.4780100309.
A method is proposed for transforming a class of models having an outcome variable with more than two levels into an equivalent binary model. The polychotomous logistic model is used to demonstrate the method. The equivalency to a simple logistic regression model after some data transformation (augmentation) is shown. The method is applied to the data from two case-control studies each with two control groups, and further applications are indicated.