Open access improves the dissemination of science: insights from Wikipedia

Wikipedia is a well-known platform for disseminating knowledge, and scientific sources, such as journal articles, play a critical role in supporting its mission. The open access movement aims to make scientific knowledge openly available, and we might intuitively expect open access to help further Wikipedia’s mission. However, the extent of this relationship remains largely unknown. To fill this gap, we analyse a large dataset of citations from the English Wikipedia and model the role of open access in Wikipedia’s citation patterns. Our findings reveal that Wikipedia relies on open access articles at a higher overall rate (44.1%) compared to their availability in the Web of Science (23.6%) and OpenAlex (22.6%). Furthermore, both the accessibility (open access status) and academic impact (citation count) significantly increase the probability of an article being cited on Wikipedia. Specifically, open access articles are extensively and increasingly more cited in Wikipedia, as they show an approximately 64.7% higher likelihood of being cited in Wikipedia when compared to paywalled articles, after controlling for confounding factors. This open access citation effect is particularly strong for articles with high citation counts or published in recent years. Our findings highlight the pivotal role of open access in facilitating the dissemination of scientific knowledge, thereby increasing the likelihood of open access articles reaching a more diverse audience through platforms such as Wikipedia. Simultaneously, open access articles contribute to the reliability of Wikipedia as a source by affording editors timely access to novel results.