We conducted a literature search using 3 databases: PubMed, PsycINFO, and EMBASE. Our search terms included “Hispanic,” “Latino,” and “Latina,” “social media,” “social network,” “social networking,” and “social network site,” as well as specific SNS names. Because SNSs are constantly evolving and changing in popularity, we used Wikipedia’s list of SNSs current to the first date of search—December 1, 2015. Of the 209 sites listed, 4 generated additional results within our query. The others were eliminated from the search terms. Using this process, our PubMed search included: (“Social Media”[Mesh] OR “social media”[tiab] OR “social network”[tiab] OR “social networking”[tiab] OR “social network site”[tiab] OR “facebook”[tiab] OR “google+”[tiab] OR “myspace”[tiab] OR “youtube”[tiab]) AND (“Hispanic Americans”[Mesh] OR “Hispanic”[tiab] OR “Hispanics”[tiab] OR “Latino”[tiab] OR “Latina”[tiab] OR “Latinos”[tiab] OR “Latinas”[tiab]) AND (“Public Health”[Mesh] OR “public health”[tiab] OR “Health Behavior”[Mesh] OR “health behavior”[tiab]).

For the other 2 databases, the query was modified to fit their search specifications. From the articles identified, we conducted a manual search of the articles’ references for other relevant studies.

Inclusion criteria included were (1) social media as a main component of study methodology or content; (2) public health topic (ie, disease prevention or health promotion efforts); (3) majority Hispanic/Latino study population (ie, ≥ 50%); (4) published between January 1, 2010, and December 31, 2015; and (5) original research study.

We restricted our search to articles published in the last 5 years given the rapidly changing nature and popularity of Internet-based technology. We excluded studies not published in English or Spanish and duplicate articles. Two reviewers independently assessed each article based on these inclusion and exclusion criteria.

After identifying studies that met inclusion criteria, the following data were extracted from each article by 2 independent reviewers: publication year, geographic location, study design, sample size, study purpose, social media type (eg, Facebook, Twitter, YouTube, and so forth), social media use (eg, recruiting study participants, promoting public health messaging, and so forth), target population (eg, age, gender, sexual orientation, and so forth), and public health topic. Data were recorded in 2 unique spreadsheets. Based on observed trends, qualitative data syntheses were performed. An inductive approach was taken to data abstraction in which specific observations were then broadened to general conclusions.

We conducted our literature search in December 2015. After our initial search on December 1, we performed weekly searches of all 3 databases to identify any newly published articles. Our final search was on December 31. Both of the reviewers used the same set of searches performed and saved during this period to conduct their independent reviews. A total of 267 articles were returned from the 3 databases: 149 from PubMed; 30 from PsycINFO; and 88 from EMBASE. Seventy-seven articles were found to be duplicates. For the remaining 190 unique articles, we reviewed the title and abstract for the selection criteria. If necessary, we also reviewed the full text of the article. Between the 2 reviewers, there was an agreement of 97% regarding which articles met inclusion criteria. Any discrepancies in group allocation or data extraction were resolved through systematic review and discussion to arrive at a consensus. In total, 26 articles met inclusion criteria. The references of these articles were then scanned, and one additional article identified was found to meet inclusion criteria. Thus, a total of 27 articles were included in the final review. See Table 1 for a brief description of each of the articles included.

All articles meeting inclusion criteria were published in the last 4 years, from 2012 to 2015. In 2012, there were 5 articles published on the topic. That number increased to 9 in 2013, 7 in 2014, and 6 in 2015. No earlier articles retrieved in the search met inclusion criteria. With regard to study location, 26 of the 27 articles (96%) detailed studies that were conducted in the United States. The one remaining study was conducted internationally with most participants coming from Central and South America.

Of the social media platforms used, Facebook was by far the most common, appearing in 24 of the 27 articles (89%). Other popular platforms included MySpace (56%), websites (44%), Twitter (30%), Craigslist (26%), and YouTube (19%). Fourteen other social media platforms, such as Instagram, Grindr, MiGente, and LinkedIn, were mentioned in the articles, although with lesser frequency. All but one study used multiple social media platforms.

The most common study design was a cross-sectional survey, which was featured in 10 of the 27 articles (37%). Most surveys were used to capture social media usage, users’ characteristics, or users’ communication preferences. The next most common study designs were qualitative studies and randomized control trials. Qualitative studies appeared in 4 of the 27 articles (15%), and randomized control trials were featured in an equal number (4 of 27, 15%). Of note, 2 of the 4 papers featuring randomized control trials are from the same study, the Harnessing Online Peer Education study, meaning that in total there were only 2 unique randomized control trials identified in this review. Of the remaining studies, there were 3 (11%) prospective cohort studies, 3 (11%) mixed methods studies, and 3 (11%) reports on public health campaigns.

All of the articles included in this review used social media for at least one of the following 3 purposes: recruiting study participants, promoting health education, or describing users/usage characteristics. Most articles (14 of 27, 52%) used social media to identify and recruit study participants. However, using social media for health education (12 of 27, 44%) and describing the characteristics of social media users were both also highly represented in the articles (12 of 27, 44%). Though less common, a few studies assessed participants’ health communication preferences (3 of 27, 11%), specifically whether they were open to receiving health information, including general public health messages and personal messages from health care providers, via social media. Finally, in 2 of the articles (7%), social media was highlighted as a way to retain study participants. See Table 2 for uses of social media by target population and health topic.

With regard to target population, most articles focused on certain populations within the Hispanic community as opposed to individuals with specific medical conditions. An overwhelming number of the articles included in this review focused on Latino men who have sex with men (MSM). Forty-four percent (12 of 27) of articles targeted this population. However, 10 of these articles derived from a single study, the Harnessing Online Peer Education study. Other populations featured included adolescents (5 of 27, 19%), the medically underserved (1 of 27, 4%), public housing residents (1 of 27, 4%), and the general Hispanic population (3 of 27, 11%). Of these groups, the most commonly targeted were Hispanic adolescents and the general Hispanic population. Although less common, individuals with specific medical conditions were the focus of a few of the studies. These conditions included pregnant women and young mothers (3 of 27, 11%), cancer survivors (1 of 27, 4%), and smokers (1 of 27, 4%). Moreover, of the 14 articles that used social media to recruit study participants, 12 (86%) targeted MSM, followed distantly by pregnant women and young mothers (1 of 14, 7%) and smokers (1 of 14, 7%). None of the articles targeted at other populations used social media for recruitment. Of the various groups targeted, MSM were also the most highly represented with regard to articles promoting health education (7 of 12, 58%), describing user characteristics (4 of 12, 33%), and retaining study participants (1 of 2, 50%).

Of the health topics featured in the included articles, sexual health was by far the most highly represented, appearing in 12 of the 27 articles (44%). Two of these articles related to sexual health and risk taking behaviors among Hispanic adolescents. The remaining 10 articles were focused on sexual risk behaviors and HIV prevention among Latino MSMs. Other health topics that featured prominently were healthy eating and active living (4 of 27, 15%), women’s health (3 of 27, 11%), and substance abuse (2 of 27, 7%). Additional topics discussed include patient-provider communication (2 of 27, 7%), body image and eating disorders (1 of 27; 4%), cancer (1 of 27; 4%), epilepsy (1 of 27; 4%), and smoking cessation (1 of 27; 4%). Of the health topics, sexual health featured prominently in articles using social media to recruit study participants (10 of 14, 71%), promote health education (6 of 12, 50%), describe user characteristics (5 of 12, 42%), and retain study participants (1 of 2, 50%).

Given Hispanic’s disproportionate risk for poor health outcomes and high affinity for social media, public health interventions that use social media may be a means of addressing the health disparities present in this community [5,9-12]. With no articles published before 2012 and 27 articles published in the last 4 years relating to the use of social media for health interventions in Hispanic populations, this is evidently a nascent field in the realm of public health for this population. Of the 27 articles, 24 related to research, whereas only 3 were reports on public health campaigns, suggesting that using social media for health interventions in Hispanics is still mostly in the descriptive phase of research. It is not yet a common part of public health practice or published research. Although almost all articles referenced studies that included Facebook (89%), most used multiple social media platforms or complemented social media with other relatively new forms of communication, such as SMS or email. This trend deviates from previous reviews in which most studies depended on a single social media platform [3,17]. While text messaging on its own has received support as a tool for behavior change in disease prevention and management, the effectiveness of Internet interventions has been enhanced when coupled with additional methods of communication, especially SMS [48-50]. These distinct platforms may engage different aspects of the behavior change process, resulting in increased effectiveness of the intervention as a whole [50]. The use of multiple communication platforms by most studies included in this review may be a product of these findings, which come from previous trials that have sought to use the Internet to address health problems in other populations.

Perhaps given the relatively young nature of the field, few articles included in this review used randomized control trials. Four of the 27 articles featured randomized control trials; however, 2 of these articles come from the same study, suggesting that the lack of rigorous trial data is even less than it initially appears. Randomized control trials may also be underrepresented because of an inherent or perceived difficulty of using this study design for social media–based trials. Barrera et al noted the challenge in striking the right balance between addressing participant expectations of a trial and developing a social media–based study recruitment tool that captured the scope of the intervention without being too burdensome for Web users to access [35]. Moreover, few social media sites offer the option for closed-access or private groups. On most sites, content is open and freely available to everyone, which does not allow for the creation of intervention and control groups as would be necessary in a randomized control trial. Facebook is one exception. Part of Facebook’s popularity in the articles included here may stem from the ability to create multiple private groups using the site, thus allowing for different exposure conditions.

Cross-sectional surveys and qualitative studies were the most highly represented study designs. These study designs align well with the way social media is currently being used for health interventions in the Hispanic population. While some studies incorporated social media in multiple ways, every article included in this review used social media for at least one of the following 3 purposes: (1) study recruitment; , (2) health education promotion; , or (3) description of users/usage characteristics. Cross-sectional surveys and qualitative studies are appropriate for such descriptive purposes. Given the current gaps in knowledge, future studies should be designed as randomized control trials to test the effectiveness of social media–based health education programs and interventions for behavior change in Hispanic populations. Of the studies that have already been conducted, there is evidence that social media can be effective in recruiting study participants [25,31,32,38], increasing health knowledge [26], encouraging participants to engage in health discussions [33], increasing rates of testing for sexually transmitted diseases [29,33], and promoting study retention [40]. Only 2 studies specifically cited the use of social media as a means of promoting retention among study participants. Because of the challenges in retaining human subjects in longitudinal studies, this area merits continued study.

With regard to target study populations, a preponderance of articles focus on Latino MSMs. Because many of these articles come out of a single study, the number of studies that use social media–driven health interventions in Latino MSMs is actually far fewer. Three unique studies feature Latino MSMs—a similar number to that for Hispanic adolescents, Latinas who are pregnant or young mothers, and the Hispanic population at large. With only a handful of studies focused on each of these populations and fewer still on other groups like the medically underserved, continued research is needed for all Hispanic populations to further explore the efficacy and potential of social media–driven health interventions. Particular attention should be directed at the medically underserved and economically disadvantaged as a potential way to address health disparities among Hispanics [5]. Due to the large number of articles focusing on social media–based HIV prevention tools in Latino MSMs, sexual health is highly represented among the health topics featured in this review. However, once again, the actual number of unique studies dealing with sexual health is far fewer such that roughly an equivalent number of studies have been conducted to examine the use of social media in sexual health, healthy eating and active living, and women’s health interventions. With only a few studies conducted on each topic, each of these merits further research, especially given the increased risk of poor health outcomes for Hispanic Americans compared with non-Hispanic, white Americans in these areas, specifically heightened risks for HIV/AIDS, obesity, diabetes, and late entry into or complete lack of prenatal care [10-12,51].

From the research that has been done, social media has been shown to be an accessible and effective method of engaging a variety of Hispanic populations in diverse health behavior change topics. Despite previous reports showing that Hispanics who are younger, more affluent, English-speaking, and native born are more likely to use social media [7-9], there is early evidence to suggest that social media can also be an effective platform for reaching other members of the Hispanic community who tend to fall outside of these categories, such as community health center patients [37]. For public health practitioners, social media holds great potential. There are already examples community-specific efforts, such as Saludable Omaha which used Facebook and YouTube to promote healthy eating and active living among Omaha’s Hispanic population [44], and nationwide campaigns, like that undertaken by the Epilepsy Foundation to increase public understanding and awareness of epilepsy among Hispanics through Facebook and Twitter [46]. Public health practitioners should both encourage the use of relevant pre-existing social media resources and develop new, social media–based public health campaigns for Hispanic populations.

A number of limitations do exist to this review. We limited our search to published, peer-reviewed journals, which could reflect a publication bias and does not include studies in progress but not yet published. In addition, we limited our search to articles published in the last 5 years, meaning that we may have missed articles published earlier. Given that all articles meeting inclusion criteria were published after 2012, this is unlikely. Moreover, because of the rapidly changing nature and popularity of Internet-based technology, what may have been relevant and effective over 5 years ago may be outdated today.

Hispanics are at increased risk for poor health outcomes, such as obesity, diabetes, and HIV/AIDS. Given that Hispanics are among the leading users of social media in the United States, there is an opportunity to use this technology for health interventions. Although a relatively new field, use of social media is quickly growing and a diverse array of target populations and health topics have been studied. To date, most publications are descriptive in nature and the full potential of social media–driven interventions for affecting health behavior change has yet to be fully realized in the Hispanic population.