Definition: The practice of publishing the plan for a study, including research questions/hypotheses, research design, data analysis before the data has been collected or examined. It is also possible to preregister secondary data analyses (Merten & Krypotos, 2019). A preregistration document is time-stamped and typically registered with an independent party (e.g., a repository) so that it can be publicly shared with others (possibly after an embargo period). Preregistration provides a transparent documentation of what was planned at a certain time point, and allows third parties to assess what changes may have occurred afterwards. The more detailed a preregistration is, the better third parties can assess these changes and with that the validity of the performed analyses. Preregistration aims to clearly distinguish confirmatory from exploratory research.

Related terms: Confirmation bias, Confirmatory analyses, Exploratory Data Analysis, HARKing, Pre-analysis plan, Questionable Research Practices or Questionable Reporting Practices (QRPs), Registered Report, Research Protocol, Transparency

References: Haven and van Grootel (2019), Lewandowsky and Bishop (2016), Merten and Krypotos (2019), Navarro (2020), Nosek et al. (2018), & Simmons et al. (2021)

Drafted and Reviewed by: Mahmoud Elsherif, Gisela H. Govaart, Helena Hartmann, Tina Lonsdorf, William Ngiam, Eike Mark Rinke, Lisa Spitzer, Olmo van den Akker, FlĂĄvio Azevedo

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