Date of Award
Doctor of Philosophy (PhD)
Counseling Psychology & Community Services
Kara B. Wettersten
The present study explored the development and initial validation of a measure of bystander intervention behaviors in situations of sexual assault. There is a gap in existing scales using a theoretical basis when measuring bystander behaviors. The scales that do exist focus primary on bystander attitudes and are not theory driven (Banyard et al., 2005; Banyard & Moynihan, 2008; Banyard, 2008; McMahon et al., 2011). Our purpose was to develop and provide initial norming and validity information for the Bystander Antecedent Scale (BAS). The BAS assesses the attitudes, social norms, and behavioral control people experience related to bystander’s behaviors when confronted with situations involving sexual assault or potential sexual assault, in doing so is organized around the Theory of Planned Behavior (TPB; Ajzen, 2002). The BAS is comprised of four subscales that represent the three predictive components of the Theory of Planned Behavior (Ajzen 2002): Perceived Behavioral Control about their ability to intervene as a bystander; Subjective Norms to Intervene about how they believe friends might react in bystander intervention situations; and Attitudes Toward Intervening involves how helpful they believe the bystander intervention would be in situations involving sexual assault. In regard to the findings of the BAS, an orthogonal, four-factor structure emerged, which accounted for 58% if the total variance. This factor structure was representative of the three predictive components of the Theory of Planned Behavior (Ajzen, 2002), and further delineated by post assault behaviors. Cronbach’s alpha levels ranged from .83 to .87. Overall, the corresponding factors of the BAS demonstrated moderate to moderate to strong convergent validity with the Bystander Intent to Help Scale-Short Form (Banyard & Cross, 2008), the Bystander Behaviors Scale-Revised (McMahon et al., 2011), the Bystander Efficacy Scale (Banyard, 2008), and the Acceptance of Modern Myths of Sexual Aggression (Gerger et al., 2007). Similarly, the corresponding factors of the BAS demonstrated divergent validity with the Social Desirability Scale-17 (Stöber, 2001). The BAS has limitations which include a sample of participants residing primarily in the Midwestern United States, and identifying as white, heterosexual, and cisgender female. However, when further norming is completed, the BAS is a useful tool for further understanding the attitudes, social norms, and behavioral control people experience related to bystander’s behaviors when confronted with situations involving sexual assault or potential sexual assault.
Friesen-Janochoski, Ashley Jean, "Bystander Antecedent Scale: Initial Development And Validation" (2022). Theses and Dissertations. 4534.