There are a number of limitations to the current literature. Statistically significant impacts were most often seen on knowledge-based outcomes, which may not translate to meaningful reductions in youth risk behaviors. Measuring behavioral outcomes sets a high standard, entailing longer follow up and retention than most of these studies attempted. Notable exceptions include studies by Roberto et al. [14] and Tortolero et al. [10], both of which demonstrated significantly reduced risk of sexual initiation among high school students.
Our review raises a number of methodological issues to be considered in future research. First, some interventions were delivered in the schools, whereas others reached youth outside of formal educational settings. Some researchers have shown that in-school interventions can be limited by filters placed on Web sites to prevent examining sexual and reproductive health information, and some students may have limited access to Internet use at home [31]. Second, these studies highlight the roles and responsibilities of researchers when using new digital media for sexual health promotion, as well as best practices for entering youth-driven environments to learn from and with youth in ways that are engaging and empowering. For example, should young peoples’ public SNS profile pages be subject to analysis or enrollment in an intervention to which they did not consent? Finally, the majority of studies reviewed were RCTs, the gold standard of study design and an important precedent for future
research in this area. The RCT process, however, can be laborious, with timelines that are inconsistent with the paces of technology and youth culture. Perhaps alternative approaches to evaluation are needed, ones that are more aligned with the flexibility and adaptability of new digital media.
Our review has a number of strengths. We provide a systematic evaluation of peer-reviewed literature from a new area of research that has not been well described. Our focus on new digital media allowed us to capture a rich array of studies, behaviors,and audiences. Some limitations must also be noted. First, we subjected an emerging field to a detailed review. Until recent years, few studies were funded and few researchers were willing to risk working with the changing technology landscape and related research methodologies. However, a review can set baseline standards and help current and future researchers learn from the experience of their peers. Second, we adopted a specific definition of new digital media. One can argue that interventions that share characteristics with those in our included studies do not appear in this review—for example, CD-ROMs or computer program interventions. New digital media, as defined by us, is user controlled and shareable. Some of the reviewed studies demonstrate why these two properties are critical, as reaching a large population could magnify the effects of an intervention. Third, the review criteria may have resulted in the inclusion of studies that may not initially seem like new digital media. For example, we included a mobile phone-based intervention in which the phone was used for calling rather than for a textmessage-based intervention. This particular study was included after much consideration by the research team, as we felt that emphasis on distributed mobile phones met our inclusion criteria, although one can argue that a call on a mobile phone is not user controlled or shareable. Fourth, we may have missed interventions in our research. We reviewed eight databases, the reference sections of all included articles, and studies from all over