Image source: Open Science Badge from the Centre for Open Science
Preregistration is a detailed description of a research study specifying the research design, hypotheses, data collection procedures, and an analysis plan before commencement of the study or data collection. Preregistrations are made open in a registry and time-stamped in non-editable file, providing transparency to the registered research, facilitating reproducibility, and minimizing risks of study bias, selective reporting and other questionable research practices.
As one of the open science practices, preregistration facilitates transparency and reproducibility of the research as it outlines a detailed account of the study design, methodology, and analysis plan. This enables peer reviewers and other researchers to assess the study's validity and reliability.
Preregistration could help prevent certain research practices that threaten the integrity of the scientific process, such as HARKing (Hypothesizing After the Results are Known) and p-hacking (manipulating data or analyses to achieve statistically significant results). They can lead to false or misleading conclusions; thus, these questionable practices could potentially affect the credibility and reputation of the researchers and be harmful to science. Preregistration helps mitigate these issues by facilitating commitment to a specified research method and analysis plan which were already shared openly before research began.
Preregistering research is more common in research relying on data collected from experiments, such as clinical trials and studies in health sciences and psychology. However, in recent years more scholars from other disciplines like economics and political science are adopting the preregistration practices (Ferguson et al., 2023). Along with the increasing adoption of open science principles, preregistration is expected to be gaining popularity across other hypothesis-driven scientific or medical fields.
The World Health Organization (WHO) defines a clinical trial as “any research study that prospectively assigns human participants or groups of humans to one or more health-related interventions to evaluate the effects on health outcomes.”
There are international standards and requirements well established for clinical trials preregistration. In 2005, the International Committee of Medical Journal Editors (ICMJE) began to require registration in a public trials' registry as a condition of consideration for publication for its member journals (De Angelis, C. et al., 2004). Other regulations from international bodies and organizations, such as the U.S. Food and Drug Administration Amendments Act (FDAAA) and World Medical Association Declaration of Helsinki also specify registration of a clinical trial as a requirement.
ClinicalTrials.gov is a U.S. website and online database of clinical research studies and information about their results. It contains studies conducted in the U.S. and around the world.
A list of primary registries in the WHO Registry Network
A list of ICMJE approved registry
The HKU Clinical Trials Registry
More resources on conducting clinical trials can be found at The University of Hong Kong Clinical Trials Centre (HKU-CTC).
Registered Reports is a publishing format that emphasizes the importance of the research question and the quality of methodology by conducting peer review prior to data collection. High quality protocols are then provisionally accepted for publication if the authors follow through with the registered methodology (Centre for Open Science, 2024).
A Registered Report refers to a new publishing model in which an original research article will undergo a two-stage peer review process.
In stage 1, the research methods and proposed analyses will go through peer-review prior to data collection. The peer-reviewed study design might be accepted for publication in journal, or pre-registered on a registry. Researchers would then commerce data collection and write up the final report.
In stage 2, the completed manuscript with study results and discussions will be peer-reviewed again mainly for the sake of ensuring no unjustified deviation of pre-registered protocol.
Image source: Centre for Open Science
Registered Reports (RRs) were proposed in 2012 to counter questionable research practices (Chambers & Tzavella, 2022). Over 300 journals currently adopt the Registered Reports publishing format according to the Center for Open Science in its complied list of participating journals. For example, Springer Nature uses the Figshare repository for publishing the Registered Reports in its journals.
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OSF Registries is run by the Centre for Open Science, widely used by scholars from multiple disciplinaries for preregistering research studies. It offers various preregistration templates for different purposes and detailed guidelines. |
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AsPredicted.org is a preregistration platform funded by the Wharton School of the University of Pennsylvania and managed by the Wharton Credibility Lab. |
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Protocols.io is a platform designed for developing, sharing, and publishing methods and protocols. |
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Peer Community In (PCI) Registered Reports* is a non-profit, non-commercial community platform for receiving, reviewing, and recommending Registered Reports (RRs) across the full spectrum of STEM, medicine, the social sciences and humanities.
*PCI RR is a community open science initiative supporting open peer review. |
PROSPERO is a global registry for protocol registrations of systematic reviews, rapid reviews and umbrella reviews in health and social care, welfare, public health, education, crime, justice, and international development, where there is a health-related outcome.
More registries can be found in our library guide on systematic review.
PreReg in Psychology is a domain-specific registry for psychological science, provided by the Leibniz Institute for Psychology (ZPID).
AEA RCT Registry is The American Economic Association (AEA)’s registry for randomized controlled trials, established for economics and other social sciences.
Centre for Open Science. (2024). Registered Reports: Peer review before results are known to align scientific values and practices. https://www.cos.io/initiatives/registered-reports#RR
Chambers, C. D., & Tzavella, L. (2022). The past, present and future of Registered Reports. Nature Human Behaviour, 6(1), 29–42. https://doi.org/10.1038/s41562-021-01193-7
De Angelis, C., Drazen, J. M., Frizelle, F. A., Haug, C., Hoey, J., Horton, R., Kotzin, S., Laine, C., Marusic, A., Overbeke, A. J., Schroeder, T. V., Sox, H. C., Van Der Weyden, M. B., & International Committee of Medical Journal Editors (2004). Clinical trial registration: a statement from the International Committee of Medical Journal Editors. CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne, 171(6), 606–607. https://doi.org/10.1503/cmaj.1041281
Ferguson, J., Littman, R., Christensen, G., Levy Paluck, E., Swanson, N., Wang, Z., Miguel, E., Birke, D. & Pezzuto, J-H. (2023). Survey of open science practices and attitudes in the social sciences. Nature Communications, 14, 5401. https://doi.org/10.1038/s41467-023-41111-1
Kupferschmidt, K. (2018, September 21). More and more scientists are preregistering their studies. Should you? Science. https://doi.org/10.1126/science.aav4786
Linsay, D. S., Simons, D. J. & Lilienfeld, S. O. (2016, November 30). Research Preregistration 101. Association for Psychological Science (APS) Observer. https://www.psychologicalscience.org/observer/research-preregistration-101
Simmons, J., Nelson, L., & Simonsohn, U. (2021). Pre‐registration: Why and How. Journal of Consumer Psychology, 31(1), 151–162. https://doi.org/10.1002/jcpy.1208
The University of Melbourne Library. (2024). Preregistering Research. https://library.unimelb.edu.au/open-scholarship/preregistering_research
World Health Organization. (2024). Glossary, Clinical trial. https://www.who.int/clinical-trials-registry-platform/about/glossary