Beyond WEIRD: The Persistence of Limited Samples and Overgeneralisation in Psychological Science (preprint)

Psychological research has been overwhelmingly restricted to WEIRD (Western, educated, industrialised, rich and democratic) countries making up only approximately 12% of the world's population. Moreover, despite documented cultural differences in things such as brain organisation, most psychological researchers tend to overgeneralise their conclusions beyond WEIRD samples. In essence whilst there has been an increasing awareness of these issues involving WEIRD dominance and overgeneralisation, it remains unknown whether improvements are occurring in key psychological journals.

The focus of this study was to examine the more recent state of affairs regarding: (i) who participates in psychological research? (ii) what demographic factors tend to be reported and/or analysed? and (iii) are findings overgeneralised beyond the samples used? We investigated 45 published papers totalling 133 studies in the journal Psychological Science between June to December 2023 (6 volumes).

Samples are still overwhelmingly WEIRD (85%), culturally relevant characteristics are reported no more than half the time (i.e., 54% in abstracts and 26% in relevance statements), statistically analysed a third of the time (33%), and overgeneralisations occur nearly all the time (i.e., 97% in abstracts and 94% in relevance statements and discussions). Despite increasing attention to the WEIRD problem and overgeneralisation, their persistence remains. More urgency is required, and suggestions are offered for going forward.

Improving sample diversity and reducing overgeneralisations matters if we are to understand how human minds work across the planet.