Clinical trials, systematic reviews and guidelines compare bene-ficial and non-beneficial outcomes following interventions. Of-ten, however, various studies on a particular topic do not address the same outcomes, making it difficult to draw clinically useful conclusions when a group of studies is looked at as a whole [1].
This problem was recently thrown into sharp focus by a system-atic review of interventions for preterm birth prevention, which found that among 103 randomised trials, no fewer than 72 different outcomes were reported [2]. There is a growing recog-nition among clinical researchers that this variability undermines consistent synthesis of the evidence and that what is needed is an agreed standardised collection of outcomes—a“core outcomes set”—for all trials in a specific clinical area [1]. Recognising that
the current inconsistency is a serious hindrance to progress in our specialty, the editors of over 50 journals related to women’s health have come together to support The CoRe Outcomes in WomeN’s health (CROWN) Initiative (Box 1).