Prospective study designs in outcomes research: the case of migraine.

Patient-reported outcomes (PROs), including resource utilisation, productivity and quality of life, are important outcomes in the field of migraine. Clinical trials have begun to incorporate PROs; however, not all research questions can be answered fully within the framework of a clinical trial design. Other prospective designs, including effectiveness trials, observational studies, and study hybrids may be used to answer many of the different research questions related to PROs. This paper reviews prospective study designs, their strengths and weaknesses, and examples of their application in migraine health-outcomes research. Guidance is provided for researchers in the selection of prospective research designs and the incorporation of PROs-research objectives.