title: The use of social networking sites for public health practice and research: a systematic review.
abstract: BACKGROUND
  Social networking sites (SNSs) have the potential to increase the reach and efficiency of essential public health services, such as surveillance, research, and communication.
  
  
  OBJECTIVE
  The objective of this study was to conduct a systematic literature review to identify the use of SNSs for public health research and practice and to identify existing knowledge gaps.
  
  
  METHODS
  We performed a systematic literature review of articles related to public health and SNSs using PubMed, EMBASE, and CINAHL to search for peer-reviewed publications describing the use of SNSs for public health research and practice. We also conducted manual searches of relevant publications. Each publication was independently reviewed by 2 researchers for inclusion and extracted relevant study data.
  
  
  RESULTS
  A total of 73 articles met our inclusion criteria. Most articles (n=50) were published in the final 2 years covered by our search. In all, 58 articles were in the domain of public health research and 15 were in public health practice. Only 1 study was conducted in a low-income country. Most articles (63/73, 86%) described observational studies involving users or usages of SNSs; only 5 studies involved randomized controlled trials. A large proportion (43/73, 59%) of the identified studies included populations considered hard to reach, such as young individuals, adolescents, and individuals at risk of sexually transmitted diseases or alcohol and substance abuse. Few articles (2/73, 3%) described using the multidirectional communication potential of SNSs to engage study populations.
  
  
  CONCLUSIONS
  The number of publications about public health uses for SNSs has been steadily increasing in the past 5 years. With few exceptions, the literature largely consists of observational studies describing users and usages of SNSs regarding topics of public health interest. More studies that fully exploit the communication tools embedded in SNSs and study their potential to produce significant effects in the overall population's health are needed.
authors.affiliation: dcapurro@med.puc.cl.
authors.forename: Daniel
authors.initials: D
authors.lastname: Capurro
authors.forename: Kate
authors.initials: K
authors.lastname: Cole
authors.forename: Maria I
authors.initials: MI
authors.lastname: Echavarría
authors.forename: Jonathan
authors.initials: J
authors.lastname: Joe
authors.forename: Tina
authors.initials: T
authors.lastname: Neogi
authors.forename: Anne M
authors.initials: AM
authors.lastname: Turner
mesh_terms: D000293:Adolescent; D000328:Adult; D035843:Biomedical Research; D006801:Humans; D015980:Public Health Practice; D061108:Social Media / Q000706:statistics & numerical data*; D060756:Social Networking; D019966:Substance-Related Disorders; D014481:United States; D055815:Young Adult
keywords: health communication; public health; public health informatics; social network