Development of a core outcome set and identification of outcome measurement tools for interventions after stillbirth (International Collaboration for Harmonising Outcomes fOr Stillbirth ResEarch: ICHOOSE)

Background
A wide range of interventions are offered to parents following the diagnosis of stillbirth. Examples include seeing birthing options, counselling and care in subsequent pregnancies. Many of these interventions have not been proven to help parents and overall evidence is limited (1,2). Furthermore, researchers do not know how to define and measure the success of these interventions.

There is a need to develop and evaluate evidence-based interventions for parents experiencing stillbirth. It is essential to establish a minimum set of outcomes, or core outcome set (COS), that would be acceptable, feasible and reliable to be measured whenever an intervention is implemented for bereaved parents after stillbirth. This will enable studies to be compared and combined.

Aim
Research is currently underway to develop a COS and identify outcome measurement tools for interventions after stillbirth.

Methods
Stage 1: Identifying previously reported outcomes
A systematic review is being undertaken to investigate what outcomes are reported in existing studies investigating the effects of stillbirth on parents and the wider family, and what measurement tools are currently used to measure those outcomes.

Stage 2: Identifying outcomes that are important to parents and healthcare professionals
Capturing patient perspectives is crucial in the development of a COS as they often identify outcomes not considered by other stakeholders or within the literature. Thirty parents from diverse social, ethnic and cultural backgrounds who have experienced stillbirth at a range of gestations will be interviewed. We will investigate parents’ experiences and identify the outcomes that are important for them and thus facilitate measuring the success or otherwise of interventions aimed at improve care following stillbirth. Findings will be triangulated with a healthcare professional focus group.

Stage 3: Determining the Core Outcome Set
Parents, doctors, midwives and researchers will participate in a three-round online Delphi study to prioritise outcomes identified from the systematic review and qualitative interviews in order of importance. A consensus meeting will be held to determine the core outcome set.

Stage 4: Determining how core outcomes should be measured
An in-depth quality assessment of outcome measurement instruments using consensus based methodology will be take place on short-listed outcomes derived from the Delphi Study (3).

Conclusions
The development of a COS and the selection of measurement tools to evaluate interventions after stillbirth will make a significant contribution to advancing the usefulness of research in this field and improving clinical practice. It will enable researchers to focus research and clinical care on important outcomes, to make better use of evidence and develop effective interventions for parents experiencing stillbirth.

References
[1] Huberty JL, Matthews J, Leiferman J, Hermer J, Cacciatore J. When a Baby Dies: A Systematic Review of Experimental Interventions for Women After Stillbirth. Reprod Sci. 2017 Jul;24(7):967-75.
[2] Flenady V, Wilson T. Support for mothers, fathers and families after perinatal death. Cochr Data Syst Rev. 2008;1.
[3] Prinsen CAC, Vohra S, Rose MR, Boers M, Tugwell P, Clarke M, et al. How to select outcome measurement instruments for outcomes included in a ``Core Outcome Set'' -- a practical guideline. Trials [Internet]. 2016;17(1):449. Available from: http://dx.doi.org/10.1186/s13063-016-1555-2