Women continue to be underrepresented in STEM (science, technology, engineering, and mathematics), despite scientific evidence indicating STEM aptitude is not gender differentiated. Various policy and institutional efforts have been made to improve gender diversity in STEM, yet little progress has been made. As psychological research indicates the gender gap in STEM is perpetuated by gender stereotypes, psychological interventions targeting gender stereotypes may be an important and effective approach. Thus, this doctoral research (1) examines the effectiveness of novel interventions designed to increase discernment of gender stereotypes in STEM and (2) aims to improve understanding and measurement of current gender stereotypes.

Using a multi-dimensional approach to gender-STEM stereotyping, I explore my research questions through online studies (Chapters 2, 3, and 5) as well as a field study with university engineering students (Chapter 4). Specifically, I designed and evaluated theory-driven psychological interventions based on optimised debunking and inoculation theory (Chapter 2, 3, and 4). Additionally, I examined the psychological mechanisms involved in improving gender-STEM stereotype discernment (Chapter 3 and Chapter 4). Finally, I address methodological issues in gender-trait stereotype research (Chapter 5). As the conclusions we draw in research can only be as robust as the methods we use to quantify them, I aimed to improve how we conceptualise, define, and measure gender stereotyping and the psychological processes involved.

To the best of my knowledge, this is the first research programme to examine inoculation theory in the context of stereotyping. Findings demonstrate some intervention effectiveness in improving discernment of gender stereotypes in STEM, but not endorsement of gender-trait stereotypes, application of gender stereotypes in decisionmaking, or gender-related attitudes. Additionally, participants in the inoculation conditions did not demonstrate levels of discernment to the same extent as those in the debunking conditions. This suggests that exposure to persuasive misinformation about gender stereotypes after the intervention treatment neutralised some of the treatment effects. However, findings show support for the cognitive and affective mechanisms theorised in inoculation theory (counterarguing and threat), but do not show clear support for the cognitive and affective mechanisms typically associated with stereotype interventions (logical thinking, perspective taking, and empathic concern). Finally, findings indicate that current conceptualisation and measurement of gender-trait stereotypes need to be updated. While the female-communal stereotype persists, it appears the male-agentic stereotype may have reduced in size and shifted in content. Implications, limitations, and suggested future directions are discussed.