title: Cannabis-related impairment: the impacts of social anxiety and misconceptions of friends' cannabis-related problems.
abstract: OBJECTIVE
  Socially anxious cannabis users are especially vulnerable to cannabis-related impairment, yet mechanisms underlying this vulnerability remain unclear. Socially anxious persons may use cannabis despite related problems if they believe such problems are common, and thus socially acceptable. Yet no known studies have examined the impact of beliefs regarding others' cannabis-related problems on one's own use-related problems.
  
  
  METHODS
  This study investigated the impact of beliefs about a close friend's experience with cannabis-related problems on the relationship between social anxiety and cannabis-related problems. The sample consisted of 158 (75% female) current (past-month) cannabis-using undergraduates.
  
  
  RESULTS
  Believing one's friend experienced more cannabis problems was related to experiencing more cannabis-related problems oneself. In fact, perceived friend's problems accounted for 40% of the unique variance in one's own cannabis problems. Descriptive norms (others' use) and injunctive norms (others' approval of risky use) were unrelated to the number of one's own problems. Social anxiety was related to experiencing more cannabis problems. This relation was moderated by perceived friend's problems such that greater social anxiety was related to more cannabis-related problems among participants who believed their friend experienced more cannabis-related problems. This was not the case among participants who believed their friend experienced fewer problems.
  
  
  CONCLUSIONS
  Normative beliefs regarding a close friend's cannabis problems were robustly and uniquely related to experiencing more cannabis-related impairment. Beliefs regarding friends' experience with cannabis-related problems may play an especially important role in the experience of cannabis-related problems among socially anxious users.
authors.affiliation: Louisiana State University, USA.
authors.forename: Anthony H
authors.initials: AH
authors.lastname: Ecker
authors.affiliation: Louisiana State University, USA.
authors.forename: Ashley A
authors.initials: AA
authors.lastname: Richter
authors.affiliation: Louisiana State University, USA. Electronic address: jbuckner@lsu.edu.
authors.forename: Julia D
authors.initials: JD
authors.lastname: Buckner
mesh_terms: D000328:Adult; D001007:Anxiety / Q000523:psychology*; D005260:Female; D033062:Friends / Q000523:psychology*; D006801:Humans; D008297:Male; D002189:Marijuana Abuse / Q000523:psychology*; D010379:Peer Group; D012938:Social Perception; D013334:Students / Q000523:psychology*; D011795:Surveys and Questionnaires; D014495:Universities; D055815:Young Adult
keywords: Cannabis; Cannabis-related problems; Marijuana; Perceived norms; Social anxiety