4  Preregistration

A preregistration specifies the research questions and the analysis plan before conducting the study. As such it allows to clearly distinguish the testing of a hypothesis with new data from the generation of hypotheses with existing observations, making reserach more robust, replicable and transparent (Nosek et al. 2018).

Preregistering a study does not imply that you cannot conduct any additional exploratory analyses or change plans after data are collected. It will merely clarify the differences between analyses decided a priori and those decided after looking at the data. If a publication derives from a preregistered study, which is common, it is important to disclose and justify the changes transparently in the manuscript.

Preregistration has some additional benefits:

• Preregistration can prevent unnecessary repetition of animal studies since it promotes systematic search of preceding studies and helps formulating relevant research questions.
• Much of the information included in a preregistration is often required for ethical approval, so the effort investing in elaborating a preregistration can be relatively low. In fact, having a well-defined analysis plan can facilitate the analytic decision process and save time in later stages of a research project.

We recommend adopting one of the preregistration forms listed below. The simplest option, such as a minimal template for a preregistered research plan, is a good starting point.

4.1 Forms of preregistration

• Preregistration. Consists in registering a research plan (hypotheses, methods, analyses) before an study is conducted. A preregistration does not necessarily have to be public, as long as it is registered and time-stamped on a trusted platform. Read more on https://www.cos.io/initiatives/prereg.

• Registered reports. Involve a two-stage peer review process where a study proposal is reviewed before data collection and the final manuscript is reviewed after analysis. At stage 1, researchers can obtain in-principle acceptance, so even if no statistically significant results are found in the planned analyses, the paper would be accepted for publication. Read more on https://www.cos.io/initiatives/registered-reports and in  Hardwicke and Ioannidis (2018).

• Peer community in registered reports (PCI-RR). The PCI initiative is a researcher-run initiative that publishes peer-reviews of preprints and the PCI-RR community is dedicated to receiving, reviewing and recommending registered reports across disciplines. Read more on this topic and find a list of PCI-RR friendly journals on https://rr.peercommunityin.org/about/

4.2 Selected resources

• Open Science Framework is a platform where you can upload and create project registration and preregistrations. It has a variety of templates in multiple formats.

• As predicted. A platform to facilitate preregistration, with a focus on using very simple and easy to fill in questionnaire. Answering the simple questions (see this sample) of the questionnaire will generate a time-stamped single page .pdf document with a unique URL for verification. You cannot import templates from other preregistration platforms into AsPredicted but you can use the document from AsPredicted in other platforms (e.g., OSF).

• Preclinical EU. A platform aimed at providing a comprehensive data base of preclinical animal study protocols. Studies can be registerred anonymously, free of charge and with an optional embargo period. Its adoption after 3 years was evaluated in a report Van Der Naald et al. (2022).

• Animal registry. An online registry for scientific studies involving animals conducted around the world.

• Animal welfare science template. Adapted from the Open Science Framework’s generic preregistration template. It highlights and gives examples relevant to animal welfare research. Developed as part of the COST action Lifting Farm Animal Lives (LIFT).

Hardwicke, Tom E., and John P. A. Ioannidis. 2018. “Mapping the Universe of Registered Reports.” Nature Human Behaviour 2 (11): 793–96. https://doi.org/10.1038/s41562-018-0444-y.

Nosek, Brian A., Charles R. Ebersole, Alexander C. DeHaven, and David T. Mellor. 2018. “The Preregistration Revolution.” Proceedings of the National Academy of Sciences 115 (11): 2600–2606. https://doi.org/10.1073/pnas.1708274114.

Van Der Naald, Mira, Steven A J Chamuleau, Julia M L Menon, Wim De Leeuw, Judith De Haan, Dirk J Duncker, and Kimberley Elaine Wever. 2022. “Preregistration of Animal Research Protocols: Development and 3-Year Overview of Preclinicaltrials.eu.” BMJ Open Science 6 (1). https://doi.org/10.1136/bmjos-2021-100259.