title: An exploration of social circles and prescription drug abuse through Twitter.
abstract: BACKGROUND
  Prescription drug abuse has become a major public health problem. Relationships and social context are important contributing factors. Social media provides online channels for people to build relationships that may influence attitudes and behaviors.
  
  
  OBJECTIVE
  To determine whether people who show signs of prescription drug abuse connect online with others who reinforce this behavior, and to observe the conversation and engagement of these networks with regard to prescription drug abuse.
  
  
  METHODS
  Twitter statuses mentioning prescription drugs were collected from November 2011 to November 2012. From this set, 25 Twitter users were selected who discussed topics indicative of prescription drug abuse. Social circles of 100 people were discovered around each of these Twitter users; the tweets of the Twitter users in these networks were collected and analyzed according to prescription drug abuse discussion and interaction with other users about the topic.
  
  
  RESULTS
  From November 2011 to November 2012, 3,389,771 mentions of prescription drug terms were observed. For the 25 social circles (n=100 for each circle), on average 53.96% (SD 24.3) of the Twitter users used prescription drug terms at least once in their posts, and 37.76% (SD 20.8) mentioned another Twitter user by name in a post with a prescription drug term. Strong correlation was found between the kinds of drugs mentioned by the index user and his or her network (mean r=0.73), and between the amount of interaction about prescription drugs and a level of abusiveness shown by the network (r=0.85, P<.001).
  
  
  CONCLUSIONS
  Twitter users who discuss prescription drug abuse online are surrounded by others who also discuss it-potentially reinforcing a negative behavior and social norm.
authors.affiliation: Computational Health Science Research Group, Department of Health Science, Brigham Young University, Provo, UT, USA. Carl_Hanson@byu.edu
authors.forename: Carl Lee
authors.initials: CL
authors.lastname: Hanson
authors.forename: Ben
authors.initials: B
authors.lastname: Cannon
authors.forename: Scott
authors.initials: S
authors.lastname: Burton
authors.forename: Christophe
authors.initials: C
authors.lastname: Giraud-Carrier
mesh_terms: D006801:Humans; D020407:Internet; D055553:Prescription Drugs; D012931:Social Environment; D061108:Social Media; D019966:Substance-Related Disorders / Q000209:etiology* / Q000523:psychology*
chemical_list: D055553:Prescription Drugs
keywords: Twitter; prescription drug abuse; social circles; social media