"During the course of treatment, many treatment seekers stopped using the drugs that they reported using at entry to the study. Lower rates of drug use were recorded at each follow-up. Furthermore, those that continued to use tended to use less. Most of the changes observed occurred by first follow-up. For most forms of drug use, no particular treatment modality was more associated with cessation than any other and the route into treatment (CJS or non-CJS) did not influence drug-use outcomes.

"The proportion using each drug reduced significantly between baseline and follow-up (Figure 5). Most of this change occurred by first follow-up; indeed use of some drug types increased marginally, and levels of abstinence from all drugs decreased between first and second follow-up.

"The proportion of treatment seekers using heroin, crack, cocaine, amphetamine or benzodiazepines decreased between baseline and follow-up by around 50 per cent; the proportion using non-prescribed methadone or other opiates such as morphine, decreased by considerably more; but the proportion using cannabis or alcohol decreased by considerably less.The proportion who reported each drug to be causing problems fell substantially for all drug types, suggesting that continued use was often, in the client’s view, non-problematic."

Source

Andrew Jones, et al., "Research Report 24: The Drug Treatment Outcomes Research Study (DTORS): Final Outcomes Report" (London, England: UK Government, Home Office Ministry, Research, Development & Statistics Directorate, December 2009), p. 10.
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