Interactive website with five modules to address safer sex motivation, knowledge, attitudes/norms, self-efficacy, and sexual communication skills. Program takes approximately 30-45 minutes to complete.

Attention-matched control website with five modules to address an introduction to mindsets, growth mindsets of intelligence, growth mindsets of self-control, growth mindsets of people, and an integrative summary. Program takes approximately 30-45 minutes to complete.

Interactive web-based intervention with five modules: motivation, knowledge, attitudes/norms, self-efficacy, and sexual communication skills.

Program acceptability was assessed through a questionnaire that was adapted from prior acceptability surveys. Specifically, six items were included to assess six aspects of acceptability: (i) an intent to return to the website, (ii) whether one would recommend the program to a friend, (iii) whether one would use information from the program in the future, (iv) how much one liked the program, (v) how much one learned from the program and (vi) how much one felt the program kept their attention. The first three questions were coded with dichotomous response options (yes/no-unsure), whereas the last three items used a four point Likert-type scale ranging from 1=not at all to 4=a lot. For analyses, these last 3 items were dichotomized into 1=a lot and 0=not a lot.

We used the validated Self-Efficacy for HIV Prevention Scale to assess communication self-efficacy. Seven items assessed confidence communicating about sexual topics (e.g., "How sure are you that you could talk to your partner about safer sex?"). Participants responded from 1 for "couldn't do it" to 4 for "very sure." Scores were averaged with higher scores indicating greater confidence in communicating about sex (alpha = 0.82).

We assessed intentions to communicate about sex with items from the AIDS Risk Behavior Assessment. Three items captured the likelihood of communicating with a partner in the next 3 months about (1) sexual limits and boundaries, (2) STDs and pregnancy, and (3) condom use. Options ranged from 0% to 100% to indicate the likelihood of communicating with a partner. We averaged scores to create a composite (possible range 0-100); higher scores indicated greater likelihood of sexual communication (alpha = 0.84).

Interactive website with five modules to address safer sex motivation, knowledge, attitudes/norms, self-efficacy, and sexual communication skills. Program takes approximately 30-45 minutes to complete.

Safer Sex: Interactive web-based intervention with five modules: motivation, knowledge, attitudes/norms, self-efficacy, and sexual communication skills.

Program acceptability was assessed through a questionnaire that was adapted from prior acceptability surveys. Specifically, six items were included to assess six aspects of acceptability: (i) an intent to return to the website, (ii) whether one would recommend the program to a friend, (iii) whether one would use information from the program in the future, (iv) how much one liked the program, (v) how much one learned from the program and (vi) how much one felt the program kept their attention. The first three questions were coded with dichotomous response options (yes/no-unsure), whereas the last three items used a four point Likert-type scale ranging from 1=not at all to 4=a lot. For analyses, these last 3 items were dichotomized into 1=a lot and 0=not a lot.

Data on acceptability only analyzed among girls who completed the Project HEART intervention

Interactive website with five modules to address safer sex motivation, knowledge, attitudes/norms, self-efficacy, and sexual communication skills. Program takes approximately 30-45 minutes to complete.

Safer Sex: Interactive web-based intervention with five modules: motivation, knowledge, attitudes/norms, self-efficacy, and sexual communication skills.

No adverse events.