ORCID
- Kate Maslin: 0000-0001-5580-803X
Abstract
BackgroundOutcome reporting in hyperemesis gravidarum (HG) research lacks standardization, which hampers the aggregation of data. A core outcome set (COS) for HG research has been developed to increase standardization. While a COS represents which key outcomes should be measured, it does not describe how and when they should be measured. Our aim was to develop a consensus-based core outcome measurement set for HG complementing the existing COS for HG.MethodThis study included multiple phases: (1) systematic review to identify all existing outcome measurement instrument (OMI)s in HG research; (2) a consensus meeting with the steering committee of this study to vote for one best OMI per outcome; (3) a modified Delphi consultation survey of at least 100 stakeholders including patients, obstetric healthcare professionals, other healthcare professionals and researchers to achieve consensus on one OMI per outcome.ResultsThe literature review identified 362 unique OMIs in 461 studies. The modified Delphi consultation round included 155 stakeholders including researchers (12.3%), women or families with lived experiences (51%), obstetric healthcare professionals (20%), and other healthcare professionals (12.9%) representing 10 countries. We achieved consensus (> 70% agreement) on all 24 OMIs presented during the Delphi survey including validated questionnaires such as the Pregnancy Unique Quantification of Emesis 24 h (PUQE-24) score and the EQ-5D-5 L as well as standardized definitions for outcomes such as preterm birth and babies small-for-gestational-age. Consensus was achieved on an OMI for each outcome included in the COS.ConclusionsWe developed a consensus-based set of core outcome measurements to record the previously established COS for studies in HG. This core outcome measurement set describes how outcomes included in the COS should be measured and reported. The COS and core outcome measurement set should be used in all future HG trials. This will help further standardize outcome selection, collection, and reporting in HG trials.
DOI Link
Publication Date
2026-07-03
Publication Title
BMC Pregnancy and Childbirth
Volume
26
Issue
1
Acceptance Date
2025-07-11
Deposit Date
2026-07-06
Funding
This study did receive funding from the Bikkja Trust 2021 Grant (TLT-TLT.FID7363213).
Additional Links
https://pubmed.ncbi.nlm.nih.gov/42399837/#full-view-affiliation-10
Keywords
CROWN initiative, Core outcomes, Delphi, Hyperemesis gravidarum, Outcome measurement instruments, Pregnancy
Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Recommended Citation
Maslin, K. (2026) 'A core outcome measurement set for hyperemesis gravidarum research: a consensus study', BMC Pregnancy and Childbirth, 26(1). Available at: 10.1186/s12884-025-07937-x
