title: Transition to injecting drug use in Iran: A systematic review of qualitative and quantitative evidence.
abstract: BACKGROUND
  Injection drug use, a behavior associated with significant adverse health effects, has been increasing over the past decade in Iran. This study aims to systematically review the epidemiological and qualitative evidence on factors that facilitate or protect the transition to injection drug use in Iran.
  
  
  METHODS
  We conducted electronic searches in five international (Medline, Web of Science, EMBASE, CINAHL, PsycINFO), one regional (IMEMR) and three Iranian (Iranmedex, Iranpsych, IranDoc) databases, as well as contacting experts in the field. Two trained researchers screened documents to identify relevant studies and independently dual-extracted data following pre-specified protocol. We applied principles of thematic analysis for qualitative data and applied a random effect meta-analysis model for age of first injection.
  
  
  RESULTS
  A total of 38 documents from 31 studies met eligibility criteria, from which more than 50% were implemented from 2006 to 2008. The weighted mean age of first injection was 25.8 (95% Confidence Interval: 25.3-26.2). Between 1998 and 2011, the age of first injection was relatively stable. Overall, drug users had used drugs for 6-7 years before they started injection use. Heroin was the first drug of injection in the majority of the cases. We identified factors influencing the initiation of or transition to injection use at various levels, including: (1) individual (pleasure-seeking behavior, curiosity and development of drug dependency commonly reported), (2) social and environmental (role of peer drug users in the first injection use, the economic efficiency associated with injections and the wide availability of injectable form of drugs in the market).
  
  
  CONCLUSIONS
  Harm reduction policies in Iran have almost exclusively focused on drug injectors in Iran. However, given the extent of the non-injection drug use epidemic, evidence from this study can provide insight on points of interventions for the prevention of the transition to injection use.
authors.affiliation: Iranian National Center for Addiction Studies (INCAS), Iranian Institute for Reduction of High-Risk Behaviors, Tehran University of Medical Sciences, No. 486, South Karegar Ave., Postal Code: 1336616357, Tehran, Iran.
authors.forename: Afarin
authors.initials: A
authors.lastname: Rahimi-Movaghar
authors.affiliation: Iranian Research Center for HIV/AIDS (IRCHA), Iranian Institute for Reduction of High-Risk Behaviors, Tehran University of Medical Sciences, Imam Khomeini Hospital, Keshavarz Blvd., Postal code: 14197-33141, Tehran, Iran.
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Amin-Esmaeili
authors.affiliation: Iranian National Center for Addiction Studies (INCAS), Iranian Institute for Reduction of High-Risk Behaviors, Tehran University of Medical Sciences, No. 486, South Karegar Ave., Postal Code: 1336616357, Tehran, Iran.
authors.forename: Behrang
authors.initials: B
authors.lastname: Shadloo
authors.affiliation: Iranian National Center for Addiction Studies (INCAS), Iranian Institute for Reduction of High-Risk Behaviors, Tehran University of Medical Sciences, No. 486, South Karegar Ave., Postal Code: 1336616357, Tehran, Iran; School of Advanced Technologies of Medicine, Tehran University of Medical Sciences, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Noroozi
authors.affiliation: Institute for Health Policy Studies and Global Health Sciences, University of California San Francisco, 3333 California Street, Suite 265, San Francisco, CA 94118, USA. Electronic address: MMalekinejad@ucsf.edu.
authors.forename: Mohsen
authors.initials: M
authors.lastname: Malekinejad
mesh_terms: D017668:Age of Onset; D040261:Harm Reduction; D006556:Heroin Dependence / Q000453:epidemiology*; D006801:Humans; D007492:Iran / Q000453:epidemiology; D015819:Substance Abuse, Intravenous / Q000453:epidemiology*; D019966:Substance-Related Disorders / Q000453:epidemiology*
keywords: First injection episode; Harm reduction; Iran; Protective factors for injecting; Risk factors for injecting; Substance use; Systematic review