Practical routes to preregistration: a guide to enhanced transparency and rigour in neuropsychological research.

Preregistration is the act of formally documenting a research plan before collecting (or at least before analysing) the data. It allows those reading a final research report to know which aspects of a study were decided before sight of the data, and which were added later. This enables informed evaluation of the severity with which scientific claims have been tested. We, as the British Neuropsychological Society Open Research Group, conducted a survey to explore awareness and adoption of open research practices within our field. Neuropsychology involves the study of relatively rare or hard-to-access participants, creating practical challenges that, according to our survey, are perceived as barriers to preregistration. We survey the available routes to preregistration, and suggest that the barriers are all surmountable in one way or another. However, there is a tension, in that higher levels of bias control require greater restriction over the flexibility of preregistered studies, but such flexibility is often essential for neuropsychological research. Researchers must therefore consider which route provides the right balance of rigour and pragmatic flexibility to render a preregistered project viable for them. By mapping out the issues and potential solutions, and by signposting relevant resources and publication routes, we hope to facilitate well-reasoned decision-making and empower neuropsychologists to enhance the transparency and rigour of their research. Although we focus neuropsychology, our guidance is applicable to any field that studies hard-to-access human samples, or involves arduous or expensive means of data collection.