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The effect of time spent in treatment and dropout status on rates of convictions, cautions and imprisonment over 5 years in a primary care-led methadone maintenance service

Research Type

Previously published article



Completion Date

Apr 2010

Primary Investigators

Oliver, Phillip; Keen, Jenny; Rowse, Georgina; Ewins, Elizabeth; Griffiths, Laura; Mathers, Nigel

Research Abstract

Background Methadone maintenance treatment (MMT) in primary care settings is used increasingly as a standard method of delivering treatment for heroin users. It has been shown to reduce criminal activity and incarceration over periods of periods of 12 months or less; however, little is known about the effect of this treatment over longer durations. Aims To examine the association between treatment status and rates of convictions and cautions (judicial disposals) over a 5-year period in a cohort of heroin users treated in a general practitioner (GP)-led MMT service. Design Cohort study. Setting The primary care clinic for drug dependence, Sheffield, 1999-2005. Participants The cohort comprised 108 consecutive patients who were eligible and entered treatment. Ninety were followed-up for the full 5 years. Intervention The intervention consisted of MMT provided by GPs in a primary care clinic setting. Measurements Criminal conviction and caution rates and time spent in prison, derived from Police National Computer (PNC) criminal records. Findings The overall reduction in the number of convictions and cautions expected for patients entering MMT in similar primary care settings is 10% for each 6 months retained in treatment. Patients in continuous treatment had the greatest reduction in judicial disposal rates, similar to those who were discharged for positive reasons (e.g. drug free). Patients who had more than one treatment episode over the observation period did no better than those who dropped out of treatment. Conclusions MMT delivered in a primary care clinic setting is effective in reducing convictions and cautions and incarceration over an extended period. Continuous treatment is associated with the greatest reductions.


ADDICTION 105(4), 732-739

Primary Keywords

Crime; heroin; methadone; methadone maintenance treatment; MMT; primary care

Contact name: Oliver, P
Contact organisation: Univ Sheffield, Acad Unit Primary Med Care, Sch Med & Biomed Sci, No Gen Hosp, Samuel Fox House, Sheffield S5 7AU, S Yorkshire England
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Submitted by Adrian Hayes, email