An introductory note to CHMP guidelines: choice of the non-inferiority margin and data monitoring committees.

The Committee on Medical Products for Human Use (CHMP) has recently issued two new guidance documents that are of particular note to statisticians. The purpose of this short note is to give a little background to the origins of these documents and a flavour of some of their most important features. The two guidelines are reproduced as the next two papers in the journal.