Study preregistration: an early example and analysis.

Preregistration is commonly seen as an effective way of reducing questionable research practices within psychology. This procedure happens prior to data collection/analysis and usually involves either sending in a research plan to a study registry or submitting a registered report. A prototype of registered reports operated within parapsychology long before mainstream psychology, and recent research showed that these reports contained fewer significant results than traditional journal articles. The current study builds on this work by examining the efficacy of another early preregistration procedure within parapsychology, namely the Koestler Parapsychology Unit's Study Registry (KPU SR). This initiative began in 2012, has attracted almost a hundred submissions, and continues to operate. The outcomes of studies preregistered on the KPU SR were compared with those of non-preregistered parapsychology studies published in journals during the same time period. In line with previous work within mainstream psychology, the preregistered studies contained fewer significant results (16%) than non-preregistered experiments (46.6%). The implications of these findings for preregistration are discussed along with suggestions for future research.