Crush: A Randomized Trial to Evaluate the Impact of a Mobile Health App on Adolescent Sexual Health



      Mobile technology allows delivery of sexual and reproductive health (SRH) information directly to youth. We tested the efficacy of Crush, a mobile application aimed at improving sexual health by promoting the use of SRH services and contraception among female adolescents.


      We recruited 1,210 women aged 14–18 years through social media advertising and randomized them into a Crush intervention group and a control group that received a wellness app. At 3 and 6 months post randomization, we compared changes from baseline in behaviors, attitudes, self-efficacy, perceived social norms, birth control knowledge, perceived control and use intentions, and SRH service utilization. Odds ratios were estimated with multivariable logistic regression and adjusted for baseline outcome, age, race/ethnicity, mother's education, and sexual experience.


      There was no difference in accessing SRH services according to study group. Three months post baseline, Crush users had higher odds (p < .05) than control participants of reporting confidence in accessing SRH services (adjusted odds ratio [aOR] = 1.6, 95% confidence interval [CI]: 1.1–2.3) and of believing that it is a good thing to use birth control consistently (aOR = 2.3, 95% CI: 1.4–3.8). Six months after baseline, Crush users had higher odds than control participants of reporting they can control whether birth control is used every time they have sex (aOR = 1.8, 95% CI: 1.2–2.6) and perceiving they would get pregnant if they did not use birth control (aOR: 1.5, 95% CI: 1.1–2.2). Impacts on other behavioral constructs were also found.


      Crush was associated with improvements in knowledge, attitudes, and self-efficacy related to key SRH behaviors and may be a strategy to deliver SRH education to adolescent women. Studies including larger numbers of sexually active adolescents are needed to demonstrate behavioral impacts.


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