Pharmaceutical Statistics Using SAS

12.8. Sensitivity Analysis

Sensitivity to model assumptions has been reported for about two decades (Verbeke and Molenberghs, 2000; Molenberghs and Verbeke, 2005). In an attempt to formulate an answer to these concerns, a number of authors have proposed strategies to study sensitivity.

Broadly, we could define a sensitivity analysis as one in which several statistical models are considered simultaneously and/or where a statistical model is further scrutinized using specialized tools (such as diagnostic measures). This rather loose and very general definition encompasses a wide variety of useful approaches. The simplest procedure is to fit a selected number of (MNAR) models which are all deemed plausible or to fit one model in which a preferred ...