Table 1

Functional form of BLR, POM and restricted and unrestricted PPOM

Model

Functional form

Indication for use


Binary Logistic Model (BLM)


Response variable with two categories (Y = 0,1)


Proportional Odds Model (POM)


Originally continuous response variable, subsequently grouped, and valid proportional
odds assumption


Unrestricted Partial Proportional Odds Model (PPOMUR)*


Proportional odds assumption not valid


Restricted Partial Proportional Odds Model (PPOMR)


Proportional odds assumption not valid, and linear relationship for odds ratio (OR)
between a covariable and the response variable


Note: Y = Response variable, vector of explanatory variables = (x_{1}, x_{2}, ....., x_{p})
*Stata uses P > j vs. < = j for the probability comparison in case of PPOM.

Das and Rahman Nutrition Journal 2011 10:124 doi:10.1186/1475289110124
