Psychological skills training, mindfulness- and acceptance-based approaches, and imagery interventions showed significant moderate effects on performance in athletes compared with controls.

Effects for psychological skills training, mindfulness- and acceptance-based approaches, and imagery were no longer significant when non-randomized studies and subjective performance outcomes were removed, which suggests that the effects are unstable and that further research with robust research methodology is needed.

Improved reporting standards and the provision of datasets in open science repositories should be considered by researchers in sport psychology in the future to increase transparency and aid interpretations of results.