A core outcome set for studies investigating the management of selective fetal growth restriction in twins

ABSTRACT Background Selective fetal growth restriction occurs in monochorionic twin pregnancies where unequal placental sharing leads to restriction in the growth of just one twin. The management options include laser separation of the fetal circulations, selective reduction or expectant management, but the best treatment is not yet known. New trials in this area are urgently needed, but in this rare and complex group maximising the relevance and utility of clinical research design and outputs is paramount. A core outcome set ensures standardised outcome collection and reporting in future research. The objective of this study was to develop a core outcome set for studies evaluating treatments for selective fetal growth restriction in monochorionic twins. Methods We established an international steering group of clinicians, researchers and patients to oversee the process of core outcome set development. Outcomes reported in the literature were identified through a systematic review and informed the design of a three round Delphi survey. Clinicians, researchers and patients and family representatives participated in the survey. An international meeting of stakeholders used the modified Nominal Group Technique to consider the consensus outcomes and agree a final core outcome set. Results Ninety-six outcomes were identified from 39 studies in the systematic review. One hundred and two participants from 23 countries completed the first round of the Delphi survey. Eighty-eight completed all three rounds. Twenty-nine outcomes met the a priori criteria for consensus and were prioritised using the modified nominal group technique. Participants included researchers (n=3), fetal medicine specialists (n=3), obstetricians (n=2), neonatologists (n=3), midwives (n=4), parents and families (n=6), patient group representatives (n=3) and a sonographer. 11 core outcomes were agreed. These were live birth, gestational age at birth, birth weight, inter-twin birthweight discordance, death of surviving twin after death of co-twin, loss during pregnancy or before final hospital discharge, parental stress, procedure-related adverse maternal outcome, offspring length of stay in hospital, neurological abnormalities on postnatal imaging and childhood disability. Conclusions This core outcome set represents the consensus of a large and diverse group of international collaborators. Use of these outcomes in future trials will help to increase the clinical relevance of the research. Consensus agreement on core outcome definitions and measures are now required. This article is protected by copyright. All rights reserved.