Preregistration helps guide researchers in distinguishing between confirmatory and exploratory results—both of which are important to scientific progress, but when conflated, may reduce credibility of results. The same data should not be used to both produce and test hypotheses. Preregistration is simply a plan to define your study questions to help improve the quality and transparency of your research.
If you are planning to preregister your next study and have questions about the process and its impact on findings, we encourage you to start with The What, Why and How of Preregistration. In this workshop, COS staff provide an introductory overview to the core values of preregistration along with a demo of the straightforward OSF preregistration template workflow.
Below, we expand on several questions, submitted by workshop participants, regarding the preregistration approach and process.
Question: Is it okay to change authors (adding/deleting) after having preregistered? Can that be seen as a disadvantage for publication when the authors don't match anymore?
Answer: Oftentimes, the authors on the registration and the final publication do not match. This is usually due to the final article containing both preregistered and unregistered experiments, which is fine as long as the two are clearly labeled. We encourage you to leave authors on the preregistration if they are contributing to that preregistered work because they deserve that credit. It's okay for the author lists to not match perfectly as long as it's clear who did what and proper attribution is given.
Question: Can you recommend any (practical) resources specifically for teaching students on how to pre-register?
Answer: Check out the resources available at cos.io/prereg. We also recommend this workshop from APS, where participants were asked to identify “holes” in preregistrations and fill them in with more specific criteria https://osf.io/4acje/. We also recommend on that page: the checklists for complete analysis plans and complete reporting; the PowerPoint slides and recordings; and the Prereg Revolution.
Question: Can I use the same wording in a prereg and then the later paper? Or do I have to be careful because of self-plagiarism?
Answer: We encourage authors to use their registration verbatim, and to cite their preregistration for clarity and discoverability. Use of quotations or changed tense from the future to the past can address self-plagiarism concerns. We encourage you to use similar language from prereg to final article because it keeps it consistent and concise for the reader.
Question: How detailed should the methods be in the prereg? Should a person be able to replicate using only the prereg?
Answer: The level of detail should be enough for an interested reader to be able to replicate the methods of the original study. We encourage you to take the perspective of your future audience: what would you want to know about the study methodology and analyses to enable you to better replicate or extend that research? We also encourage concise language, as the longer the preregistration is, the less likely it will be read in its entirety (though some length is unavoidable).
Question: Should I list all measured variables from the study also in the prereg, even if they are not part of the preregistered hypotheses/analyses?
Answer: If the variables will not be used in testing the preregistered hypotheses, then you do not need to include them in the preregistration. It can sometimes be helpful to include them if you think the variables will be used in an exploratory or data-driven way, but it is not required. At a minimum, the variables used in testing preregistered hypotheses must be defined in the preregistration, and any additional variables could be included if you believe their inclusion will add clarity to the work.
Question: Can you talk more about preregistration of studies using existing data? What precautions need to be taken? What assurances need to be made in the preregistration?
Answer: It can be a bit tricky when using existing data, but it can still be useful and beneficial. With existing data, it is impossible for the reader to know how much you had known prior to creating the preregistration. If you know the data intimately and understand how the data are going to distribute, then the preregistration is very diminished in its power to mitigate bias. Preregistering what you know about that data helps the reader better assess what you knew before you began the project. This is the best you can do in certain situations. It's transparent what you knew prior to creating the registration, and then it's up to the reader and the community to assess how much, if any, bias may have crept in.
Question: Should I submit link to my preregistration project when sending my paper to a journal for publication? What about anonymity during review process?
Answer: Yes! Sharing your preregistration with the reviewers allows it to be used in the review process. As for anonymity in the review process, you can submit anonymized view-only links. NOTE: Be sure that any attached files or answers to registration questions do not contain any identifying information (including file titles!). The anonymized link removes the Author section of the form, but it cannot redact any information in a file.
Question: What types of errors in a prereg are you allowed to correct using the "short" registration process?
Answer: Updates or amendments to a preregistration are permissible (in most cases) prior to analyzing the data (up until the outcomes of the study are known). For instance, if you have preregistered an analysis plan, but learn of a better technique before you have analyzed the data, then it is still okay to update your registration since you are not aware of the results of those initial analyses. What is not okay is updating the registration after results of the initial analyses are known to shift the analyses, as it starts to enter the territory of mining for statistical significance. In this case, you are encouraged to still run those analyses, but these must be labeled as exploratory or data-driven analyses. For more information on updating a preregistration, please see this blog post: https://cos.io/blog/preregistration-plan-not-prison/
Question: What are recommended practices for reporting preregistration processes in completed studies that are being written up for publication (e.g., referencing the preregistration in the method, connecting to the preregistration itself via DOI)?
Answer: Both referencing the preregistration in the methods section and providing a link to the preregistration itself are crucial when writing up preregistered work. The preregistration was written as a means to inform your readers what had been planned in the study, so it is vital they be able to access and read it. Preregistration is a great exercise for the author, but it loses nearly all its value if it cannot be read by others.
Question: Due to the requirement for prereg/approval before data collection, is there an option for studies that use archival data?...or large public research databases?
Answer: For preregistering studies using archival or public research data, it is important to disclose your prior knowledge and exposure to the data at the time of registering. The concern is to what extent the knowledge could have influenced or biased the analytical decisions in the preregistration. Disclosure is key, but too much prior knowledge of the data can impact the usefulness of prereg from a bias mitigation perspective.
Visit cos.io/prereg for further reading and community resources.