Bourgon and Armstrong's study concluded that the principles of "risk", "need", and "responsitivity" are linked with the effectiveness of a treatment aimed to reduce reoffending.
However, the effectiveness of the treatment is hindered by the fact that the individual is in prison.
Their study separated 620 unprisoned individuals into 2 groups. 482 prisoners received treatment and 138 were left untreated. Results showed that prison-based treatment can be useful in the efforts to reduce recidivism. Additionally, there are minimum levels of treatment necessary in order to gain results. These depend heavily on an individuals "risk" and "need" factor.