Assessing the effect of multidimensional family therapy in adolescents on police arrests against a background of falling crime rates: a randomised controlled trial with 7-year follow-up

Background Earlier, we reported that multidimensional family therapy (MDFT) and cognitive behavioural therapy (CBT) decreased criminal offending in adolescents as measured with self-report in a randomised controlled trial with 1-year follow-up. The present study tested if this effect could be confirmed using police arrest data. Methods Study participants were 109 adolescents who were recruited for the Dutch part of a transnational treatment trial. National police arrest records were analysed for 3 years before the adolescents entered treatment with MDFT or CBT and for 7 years after treatment entry. Results Police arrest rates rose in the 3 years preceding treatment and then dropped in both treatment groups to almost zero level during the follow-up period. Conclusions The results suggest that MDFT and CBT both strongly and durably decreased police arrest rates. However, this conclusion remains uncertain as crime rates concurrently decreased in the general population.