Cannabis, stimulant (including cocaine) and sedative abuse was identified from the Mortality registry, providing cause and contributory cause(s) of death; the Swedish hospital discharge registry, providing all inpatient hospitalizations; and the outpatient hospital care registry, providing all consultations/diagnoses at all Swedish hospitals. Cannabis abuse was defined by ICD10 code F12 (excluding F12.5 and F12.7) and ICD9 codes 3052, 3043. Stimulant abuse was defined by ICD10 codes F14, F15 and ICD9 codes 3056, 3042, 3057, 3044. Sedative abuse was defined by ICD10 code F13 and ICD9 codes 3054, 3041. We also employed the Swedish Crime Registry that includes national data on all convictions, using references to laws covering narcotics (law 1968:64, paragraph 1, point 6) and drug-related driving offences (law 1951:649, paragraph 4, subsection 2 and paragraph 4A, subsection 2). Within those laws cannabis was defined by code 8; stimulant by codes 1, 2, 3, 4, 5, 6, 7; and sedatives by codes 17, 19.
