EXPLORING ANCOVA ANALYSIS

In many situations we carry out inferences on logarithims of quantites and then transform the results back to an interpretable scale. Thus often using normal theory, distribution of odds ratios and hazard ratios are in fact log-normal distributions. The objective is to perform an analysis of a log-normally distributed laboratory test result that is the primary endpoint. We transform to the normal distribution. An ANCOVA analysis is used on the transformed data with baseline test result as a covariate and treatment as the covariate of interest.