Recidivism occurs when someone reoffends and returns to prison. Educational and training programs in prison appear to reduce recidivism rates. The results from this meta-analysis suggest that participation in any form of educational program leads to a 14.8% decrease in the likelihood of recidivism. This effect is slightly smaller at 11.3% when restricting the results to the highest quality papers. And when considering studies published since 2010, the estimates decrease to about 7%.
A decline in effectiveness based on more recent research is not surprising. Expanding programs to less interested participants may impact the outcome. However, a decline in recidivism of between 7% to 15% is a significant success. That means, for instance, that for every 1,000 inmates served by prison education and later released, between 70 and 150 fewer will return to prison than otherwise would.