Preregistrointi

Preregistrointi, or preregistration, is the practice of documenting a study’s research plan before data collection begins and making that plan publicly accessible. In preregistration, researchers specify the research questions or hypotheses, primary and secondary outcomes, sample size and power considerations, recruitment and data collection methods, and a detailed analysis plan. The main purpose is to increase transparency and reduce questionable practices such as p-hacking and HARKing (hypothesizing after results are known).

Preregistration is widely used in scientific research, particularly in psychology, social sciences, and clinical trials. Platforms such as the Open Science Framework, AsPredicted, and ClinicalTrials.gov host preregistrations. In some fields, journals offer registered reports, where the study proposal is peer-reviewed before data collection; if accepted, the final manuscript is published regardless of outcome, provided the researchers adhere to the approved methods.

A key feature is the distinction between confirmatory and exploratory analyses. Preregistration emphasizes confirmatory analyses that follow a pre-registered plan, while exploratory analyses can be conducted but should be clearly labeled as such. Preregistration can improve reproducibility, facilitate scrutiny, and reduce selective reporting, but it may also be time-consuming and potentially constraining if rigidly applied. Critics note that preregistration cannot guarantee integrity and may not suit all research questions or adaptive study designs.

Preregistrointi is commonly discussed in the context of open science and research transparency, and it complements other practices such as data and code sharing.