NIH expands beyond Covid-19 Preprints in Phase 2 of Pilot Program

In the summer of 2020, the NIH began a pilot program to add Covid-19 related preprints featuring research funded by the NIH to its databases. Two years later, evaluations of this pilot program are positive (Funk, 2022). The National Library of Medicine (NLM) successfully managed the technical hurdles of including and properly labeling preprints into PubMed and PubMed Central (PMC). Including preprints increased the discoverability of NIH-funded research, increasing the speed of access by more than 100 days, according to one published statistic, while not decreasing trust in the NLM or its research tools. According to the NIH, indexing preprints in multiple places had value because researchers access and discover information differently. Due to the success of this pilot, the NIH is expanding its incorporation of preprints into the database and will soon start including all preprints supported by NIH funds published after January 1st, 2023 (NLM, 2022).

It is important to note that the NIH will only include preprints posted to servers that it identified during the first phase of its pilot program as having policies and practices that align both with the mission of the NIH and with recommendations made by groups such as the Committee on Publication Ethics. Eligible preprint servers currently include bioRxiv, medRxiv, arXiv, and Research Square, although the list may change over time.

In support of this new phase of its pilot program, the NIH has updated its search functions and record displays, including an updated information banner on preprint records, more prominent identification of final published journal articles on preprint records, and the ability to exclude preprints from a search as well as limit a search to preprints only (NLM, 2023). Figures 1 and 2 show how the updated peer-reviewed articles are displayed on preprints in PubMed and PMC.

At the end of 2023, the second phase of this program will be assessed to evaluate its continued success in increasing the discoverability and maximizing the impact of NIH-funded research.

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Funk, K., Zayas-Caban, T. & Beck J. (2022). Phase 1 of the NIH Preprint Pilot: Testing the viability of making preprints discoverable in PubMed Central and PubMed. BioRxiv.

National Library of Medicine. (2022, December 14). NIH Preprint Pilot accelerates and expands discovery of research results: Expansion of pilot planned for early 2023.

National Library of Medicine. (2023, January 9). Next phase of the NIH Preprint Pilot launching soon. NCBI Insights.

Figure 1. PubMed search result summary and abstract displays of a preprint and its associated peer-reviewed version.
Figure 2. The PMC view of the same preprint summary and full-text views with update notice of its peer-reviewed version.