Developing a core outcome set in interventions to prevent stillbirth: A systematic review on variations of outcome reporting

Objective: To determine which outcomes have been previously reported in previous stillbirth prevention studies. Research design: Systematic review of reviews: We searched the Cochrane Database of Systematic Reviews, EMBASE and Pubmed for systematic reviews and meta- analyses investigating interventions to prevent stillbirth and its major risk factors. Data collection and analysis: Two reviewers identified and extracted outcomes independently. Outcomes were categorised under relevant domains for analysis. Frequency of each outcome was also determined. Main results: From 51 eligible reviews, 16 reviews addressed stillbirth prevention specifically while 35 reviews evaluated the efficacies of prevention or management of the eight major risk factors of stillbirth. Two hundred and thirty-seven outcomes were extracted, including 150 maternal outcomes and 87 offspring outcomes. Stillbirth (35/51), perinatal mortality (34/51) and neonatal mortality (33/51) were the most commonly reported outcomes followed by birthweight (29/51), caesarean section (28/51) and preeclampsia/eclampsia (23/51). Self-reported mother/family focused outcomes on their experiences and views were reported in 10/51 reviews. Conclusion: In studies evaluating prevention of stillbirth there is a large variety in outcomes, with discrepancies in nomenclature and measurements. Woman/family-centred outcomes are often missing from studies. There is a need for a core outcome sets agreed by all stakeholders containing the recommended minimum data to be reported in future studies investigating prevention of stillbirth.