A Systematic Review and Meta-Analysis Examining Sex Differences in Mental Rotation Ability

Historical research has previously described sex differences in mental rotation ability. Here, we sought to determine whether such sex differences still exist via a systematic review and meta-analysis. Using the University of Nottingham's Library database, Google Scholar and PubMed, all studies investigating sex differences in mental rotation since 2010 were considered. Existing meta-analyses, along with studies that did not compare both males' and females' biological sex, used stated mental rotation tests (MRT) and did not make the full text available, were excluded. The systematic review identified 41 relevant studies, and a meta-analysis was carried out on 59 effect sizes from this sample. Analysis found that males performed better than females in mental rotation tasks, and the effect size (d = 0.60, 95% CI [0.54 to 0.67]) was of a similar magnitude to prior meta-analyses. Subgroup analysis also confirmed that the MRT produced the greatest effect size. An Eggers test reported no evidence of publication bias; however, there was significant heterogeneity within the research data. Overall, these results are consistent with previous research; however, raise questions as to why the MRT elicits significantly greater effect sizes than other mental rotation assessments.