"Examination of all clients exiting [drug treatment] in 2005-06 revealed that 46% didn’t return to drug treatment nor had a drug related contact with the CJS [criminal justice system] in the following four years. This would suggest the majority of these individuals are managing to sustain their recovery from addiction though it is not possible to confirm this from the analysis presented in this report."

Source

"A long-term study of the outcomes of drug users leaving treatment," National Treatment Agency for Substance Misuse (London, United Kingdom: September 2010), p. 9.
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