Concordance of clinical and marketing objectives in phase IV

I would like to begin by giving a general definition of ‘phase IV studies’ for the purposes of this discussion. Such studies are large scale, population-based evaluations of drugs after marketing approval has been obtained. The study protocols are consistent with approved labelling claims and are planned to observe actual clinical practice. There may be no specific scientific hypothesis other than the recording of clinical experience, and there is usually no direct selection of a control or comparison group.