Study 1
Banyard and colleagues (2007) used a randomized experiment to evaluate the effects of the Bringing in the Bystander treatment on attitudes, knowledge, and behavior on the intervention group. Participants in the study were recruited from the undergraduate cohort of the University of New Hampshire, through flyers at the student center. Participants were between the ages of 18 and 23, and were paid for their participation.
The pretest sample (n = 389) was 55.8 percent female, with an average age of 19.4 years. The sample was 90 percent white; 38 percent were in their first year (29.4 percent were sophomores, 19.8 percent were juniors, and 12.4 percent were seniors). The participants were randomized into three groups: a control group (n = 115), a one-session treatment group (n = 137), and a three-session treatment group (n = 137).
The study was implemented in two waves during successive academic years. Participants filled out pretest, posttest, and 2-month follow-up questionnaires, as well as 12-month follow ups for the first wave group and 4-month follow ups for the second-wave group. With the exception of gender at the 12-month follow up, there were no differences between groups, or waves.
The study used the same measures at all periods. These included a knowledge assessment (of sexual violence and prosocial bystander behaviors) component, the Illinois Rape Myth Acceptance Scale–Short Form, the College Date Rape Attitude Survey, bystander attitudes, behaviors and efficacy scales, and a decisional balance scale. The bystander attitudes, efficacy, and behavior measurement instruments were created and piloted by the program developers for this study.
The control group received no prevention program, completing only the questionnaire at each period. Those in the control group were also given a list of community and college resources at the posttest. The one-session group received a single 90-minute prevention session led by a team of peer leaders (one male and one female) in gender-specific groups. The three-session intervention group received three similar 90-minute sessions during a single week with expanded content.
The effects of the intervention on the three groups (and gender) were studied using repeated multiple analysis of covariance (or MANCOVA) over the pretest, posttest, and 2-month follow up. Multiple analysis of variance (or MANOVA) was used to examine differences between pre- and posttest.
The data collected at the 4-month and 12-month follow ups was only used in an exploratory analysis, since the sample sizes were much smaller (due to the different waves of collection and attrition).
Study 2
Moynihan and colleagues (2014) used a randomized experiment to evaluate the effects of Bringing in the Bystander on bystander behaviors, up to 1 year following program implementation. Participants ranged between 18 and 24 years old, were recruited from two public New England university campuses, and were paid for their participation.
Participants were first-year students who were recruited by flyers, announcements in class, weekly meetings with resident advisors, and email announcements. One campus recruited three cohorts and the other recruited two cohorts of participants.
The sample included 948 participants who took the pretest (550 and 398 from the two campuses) and was evenly distributed between men (51.5 percent) and women (47.8 percent), with three subjects identifying as transgender. The participants were mainly white (85.2 percent). There were no significant differences between the program participants and the control group at the pretest.
Approximately 2 weeks after completing the pretest, all participants on both campuses were exposed to the Know Your Power Bystander social marketing campaign for 6 weeks during the second half of the spring semester of their 1st year. Program participants took part in the Bringing in the Bystander in-person program (4.5 hrs. across multiple sessions).
Twelve months following the program, 346 participants took a follow-up survey and could be matched with the pretest data, resulting in a 36.5 percent retention rate. The only significant difference between the participants who were retained and those who were not was that the participants who completed the 12-month survey were more likely to be women (53.5 percent).
The Bystander Behavior Scale (Banyard et al. 2014) was used to measure bystander behavior related to sexual and relationship violence that a participant engaged in during the past 2 months, specifically directed at helping friends. The scale included 49 items on behaviors directed at helping a friend. For example, on item on the scale states “I expressed disagreement with a friend who said having sex with someone who is passed out or very intoxicated is okay.” Participants responded yes or no to each item. The study used longitudinal regression models to analyze the 12-month follow-up data.