Funders' Expectations for Open Science in Cardiovascular Research: A Scoping Review of the Largest Cardiovascular Research Funders.

Open science practices, including data sharing, open access, and prospective study registration, have been increasingly recognized to improve transparency, reproducibility, and accessibility in research, yet their uptake and implementation by cardiovascular research funders is unclear. We conducted a scoping review of publicly available policies, guidance, and grant instructions from 12 members of the Global Cardiovascular Research Funders Forum to assess expectations, monitoring, and support for open science in cardiovascular research. We included 105 documents from 9 funders; no relevant documents were identified for 3 funders. Data sharing (67%) and open access (58%) were the most common mandates by funders, followed by prospective registration (50%) and patient and public involvement (50%). Requirements for other practices, including code sharing, use of reporting guidelines, preprints, and open peer review, were uncommon. Monitoring compliance was inconsistent, with many funders not specifying any mechanisms, even for widely required practices. Where available, support was most often provided through financial assistance, guidance, or infrastructure, particularly for open access, data sharing, and patient and public involvement. These findings suggest that while cardiovascular funders are engaging with open science, policies remain uneven in scope, monitoring, and support. Coordinated efforts to strengthen and harmonize open science expectations, particularly around compliance monitoring and researcher training, will be essential to realizing the full potential of open science in cardiovascular research.