Introduction

Progress in science is built on a balance between curiosity and scepticism, and between creativity and rigour.1 Although progress in science inevitably needs the generating of findings that may not be verified in subsequent studies, there is a considerable risk that exploratory studies introduce bias in the body of scientific knowledge. This risk may be substantial in observational studies, including cohort studies, case–control studies and cross-sectional studies.2 Observational studies play an essential role in medical research as they are often conducted to evaluate research questions that cannot be addressed by clinical trials.3 As shown by Ioannidis, however, the likelihood that any given finding from a published observational study is true in reality is limited.2 Aside from problems of uncontrolled confounding and other biases, observational studies are often generated from databases comprising many variables. Researchers often explore an unknown quantity of potential relationships capitalising on the chance of obtaining positive findings. In this editorial, we will explore two potential solutions to reduce the risk of false positive findings from observational studies: a registration requirement; and a replication requirement.