Date of Award

Spring 2023

Degree Type

Restricted to Claremont Colleges Dissertation

Degree Name

Psychology, PhD


School of Social Science, Politics, and Evaluation

Dissertation or Thesis Committee Member

Rebecca J. Reichard

Dissertation or Thesis Committee Member

Stephen W. Gilliland

Dissertation or Thesis Committee Member

Michelle C. Bligh

Terms of Use & License Information

Terms of Use for work posted in Scholarship@Claremont.

Rights Information

© 2023 Jessica Brull Barrett Diaz


Inclusion, Psychological safety, Social identity threat, Empirical test

Subject Categories

Organizational Behavior and Theory | Psychology


Following the tidal wave of racial unrest in the summer of 2020, organizations doubled down on a broader commitment to diversity, equity, and inclusion. Central to such efforts is a focus on psychological safety. Although the original psychological safety theory makes little mention of identity, in two studies, I empirically tested a recently developed social identity theory of psychological safety. According to the theory, identity-contingent cues in an individual’s environment activate social identity threat, reducing psychological safety and inclusion through three intraindividual cognitive processes: stress-arousal, vigilance to threat-related cues, and increased self-monitoring or regulation. Prior to testing my hypotheses, I conducted a pilot study to validate adaptations of two scales (cultures of conformity and social identity threat) and establish their convergent and divergent validity. Proceeding to my primary studies, study one was a longitudinal study testing the relationship between social identity threat and psychological safety over four weeks. I collected data from 386 Prolific workers employed at least part-time for an organization with more than ten employees. Results modeled using random intercept cross-lag panel modeling found significant bi-directional causal relationships between social identity threat and psychological safety. However, exploratory analysis tested and confirmed this was only the case for BIPOC participants and not for participants who identified as white. Study two modeled the complete social identity theory of psychological safety amongst 486 full and part-time workers collected using convenience sampling. Findings supported the theory’s core propositions that identity-contingent cues in an individual’s environment trigger social identity threat, which relates to lower levels of psychological safety and inclusion. Exploratory analyses empirically demonstrated that these relationships were far stronger for BIPOC individuals compared to white participants. Study two results also supported the hypothesis that for BIPOC participants, BIPOC representation in leadership and inclusive leadership serve as promising ways to attenuate the negative effects of identity-contingent cues and resulting social identity threat, thereby safeguarding psychological safety and inclusion.



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