Megastudy: A novel experimental paradigm beyond “one-at-a-time”

Abstract: Scientific psychology aims to explore the factors influencing and altering human psychology and behavior through rigorous research designs. However, its strict experimental controls have also led to issues such as low ecological validity, reproducibility, and policy persuasiveness. Constrained by the limitations of the paradigm itself, open science practices and meta-analyses cannot resolve these problems. The recently emerging megastudy approach can simultaneously test the effects of many theory-based interventions or experimental conditions on the same outcome variable(s) within a single large-scale study. It offers higher ecological validity, reproducibility, and policy persuasiveness, and can mitigate publication bias while accelerating scientific discovery efficiency. To better facilitate the accelerated evolution of scientific psychology, researchers need also address challenges such as the high cost and management complexity of megastudies, while adopting strategies that integrate with classic experimental paradigms and AI technologies, and conduct organized large-scale scientific research collaboration.