the national anger managmenet package was trialed with offenders age 17-21, there were initial issues of not taking seriously but it was ultimately considered to be a success, offenders reported high levels of self control and increased awareness after the course. However this could be down to social desirability bias , any measure of effectiveness is a self report methods use in prison. Initially they may over report their acts of hositility or bias to appear 'hard' they also may take part as a way to get out of their cells, so their reponses would lack sincerity, may lie to get benefits