Self-reflection promotes learning in citizen science and serves as an effective assessment tool

Advances in digital technologies have given rise to 'citizen science' which engages non-professionals in scientific research and provides participants with diverse learning opportunities. However, evaluating such learning outcomes has proven challenging with many biases and unexplored dimensions. This study aimed to assess learning processes and outcomes through participation in E$$ENTIAL MEDICINE$ - a citizen science initiative which investigates the world's most important medicines using data available online. To attain an account of participants experiences as citizen scientists, we applied a self-reflection approach, engaging participants as co-researchers. Our findings highlight the learning dimensions of co-researchers which include advances in search skills and their ability to analyse and evaluate online data; increased knowledge of medicines histories, development and use; and increased understanding of the complexities of science. Learning more about the complex structures and relationships within the pharmaceutical industry, served to challenge the assumptions of participants, leading them to develop critical thinking skills. Finally, project attributes which were found to contribute to learning included interest, relevance, active participation, flexibility and repetition. This study demonstrates the important role of self-reflection in promoting and assessing learning in online environments, it expands current literature on the potential of citizen science for promoting learning and identifies key attributes for the advancement of such learning.