Evans JR, et al. - In the present study, the authors sought to describe and summarize the results reported in randomized controlled trials of multifocal vs monofocal intraocular lenses in cataract surgery using the framework of domain, measurement, metric and method of aggregation. It is difficult to collect and analyze data on outcome measures in studies of multifocal intraocular lenses during cataract surgery. As a result, the collection and reporting in the medical literature are considerably heterogeneous. It makes it hard to synthesize these data to provide accurate impact estimates, and is a potential source of research waste. Researchers in this field must produce a core result set that is informed by the views of patients and proposing an initial set of outcomes on which to base these.