Impact of supervision of methadone consumption on deaths related to methadone overdose (1993-2008): analyses using OD4 index in England and Scotland

Objective To evaluate the impact of introduction of supervision of methadone dosing on deaths related to overdose of methadone in Scotland and England between 1993 and 2008 while controlling for increased prescribing of methadone. Design Analysis of annual trends in deaths related to overdose of methadone in relation to defined daily doses of methadone prescribed. Setting Scotland and England. Population Deaths in which methadone was coded as the only drug involved or as one of the drugs implicated. Main outcome measure Annual OD4-methadone index (number of deaths with methadone implicated per million defined daily doses of methadone prescribed in that year). Results OD4-methadone declined substantially over the four epochs of four years between 1993 and 2008. It decreased significantly (P