Understanding scientific credibility: graduate students’ reasoning about epistemic practices and social certification of scientific knowledge

Understanding how scientific knowledge becomes credible is increasingly important in contemporary societies characterised by misinformation and contested knowledge claims. Although research in science education has extensively examined students’ understandings of the nature of science (NOS), less attention has been given to how learners explain the credibility of scientific knowledge, particularly the relationship between epistemic practices and institutional mechanisms. This study investigates how graduate students in science education reason about scientific credibility in response to a historical case. The study involved fourteen graduate students enrolled in science education programs, most of whom were current or former science teachers. The study employed a qualitative design using a contextualised reflection task based on the historical case of Nobel Prize-winning physicist Maria Goeppert Mayer. Participants’ written responses were analyzed using qualitative content analysis within a framework comprising two predefined analytic dimensions: epistemic practices and institutional mechanisms. The analysis revealed two main patterns. Some participants interpreted scientific credibility as emerging from the interaction between epistemic rigour and collective evaluation within scientific communities. Others treated epistemic validity as largely independent from community recognition. These findings suggest challenges in connecting epistemic practices with the institutional mechanisms through which scientific credibility is established, with implications for science education.