title: Pathways through opiate use and offending: A systematic review.
abstract: Although evidence points to a strong link between illicit drug use and crime, robust evidence for temporal order in the relationship is scant. We carried out a systematic review to assess the evidence for pathways through opiate/crack cocaine use and offending to determine temporal order.
  
  
  
  A systematic review sourced five databases, three online sources, bibliographies and citation mapping. Inclusion criteria were: focus on opiate/crack use, and offending; pre-drug use information; longitudinal design; corroborative official crime records. Rate ratios (RR) of post-drug use initiation to pre-drug use initiation were pooled using random effects meta-analysis.
  
  
  
  20 studies were included; UK (9) and US (11). All were of opiate use. Mean age at (recorded) offending onset (16.7yrs) preceded mean age at opiate-use onset (19.6yrs). Substantial heterogeneity (over 80%: unexplained by meta-regression) meant that RRs were not pooled. The RR for total (recorded) offending ranged from 0.71 to 25.7 (10 studies; 22 subsamples: positive association, 4: equivocal, 1: negative association). Positive associations were observed in 14/15 independent samples; unlikely to be a chance finding (sign test p=0.001). Individual offence types were examined: theft (RR 0.63-8.3, 13 subsamples: positive, 9: equivocal, 1 negative); burglary (RR 0.74-50.0, 9 subsamples: positive, 13: equivocal); violence (RR 0.39-16.0, 6 subsamples: positive, 15: equivocal); and robbery (RR 0.50-5.0, 5 subsamples: positive, 15: equivocal).
  
  
  
  Available evidence suggests that onset-opiate use accelerates already-existing offending, particularly for theft. However, evidence is out of date, with studies characterised by heterogeneity and failure to use a matched non-opiate-user comparison group to better-establish whether onset-opiate use is associated with additional crime.
authors: Centre for Mental Health and Safety, Institute of Brain, Behaviour and Mental Health, The University of Manchester, Manchester M13 9PL, UK. Electronic address: karen.hayhurst@manchester.ac.uk.
authors: Karen P
authors: KP
authors: Hayhurst
authors: Centre for Mental Health and Safety, Institute of Brain, Behaviour and Mental Health, The University of Manchester, Manchester M13 9PL, UK.
authors: Matthias
authors: M
authors: Pierce
authors: NIHR Health Protection Research Unit in Evaluation, School of Social and Community Medicine, The University of Bristol, Bristol BS8 2PS, UK.
authors: Matthew
authors: M
authors: Hickman
authors: School of Law, The University of Manchester, Manchester M13 9PL, UK.
authors: Toby
authors: T
authors: Seddon
authors: Centre for Biostatistics, Institute of Population Health, The University of Manchester, Manchester M13 9PL, UK.
authors: Graham
authors: G
authors: Dunn
authors: School of Computer Science and Manchester Institute of Biotechnology, The University of Manchester, Manchester M13 9PL, UK.
authors: John
authors: J
authors: Keane
authors: Centre for Mental Health and Safety, Institute of Brain, Behaviour and Mental Health, The University of Manchester, Manchester M13 9PL, UK.
authors: Tim
authors: T
authors: Millar
mesh_terms: D017668:Age of Onset; D003415:Crime / Q000706:statistics & numerical data*; D006801:Humans; D009293:Opioid-Related Disorders / Q000453:epidemiology*; D006113:United Kingdom / Q000453:epidemiology; D014481:United States / Q000453:epidemiology
keywords: Crime; Opiate use; Substance abuse; Systematic review