Table 1

Characteristics of studies evaluating drug decriminalisation or legal regulation, 1970 to 2018

CharacteristicTotal (%)
N (%)
(n=114)
Decriminalisation*
N (%)
(n=19)
Legal regulation*
N (%)
(n=96)
Country
 USA104 (91.2)10 (52.6)95 (99.0)
 Australia3 (2.6)3 (15.8)0 (0.0)
 Portugal2 (1.8)2 (10.5)0 (0.0)
 China1 (0.9)0 (0.0)1 (1.0)
 Czech Republic1 (0.9)1 (5.3)0 (0.0)
 Mexico1 (0.9)1 (5.3)0 (0.0)
 Multi-country†2 (1.8)2 (10.5)0 (0.0)
Focus of drug law reform
 Cannabis109 (95.6)15 (78.9)95 (99.0)
 Opium1 (0.9)0 (0.0)1 (1.0)
 Peyote1 (0.9)1 (5.3)0 (0.0)
 Multiple/all drugs3 (2.6)3 (15.8)0 (0.0)
Study design
 Cohort4 (3.5)0 (0.0)4 (4.2)
 Controlled before-and-after26 (22.8)6 (31.6)20 (20.8)
 Interrupted time series6 (5.3)0 (0.0)6 (6.3)
 Repeated cross-sectional74 (64.9)11 (57.9)64 (66.7)
 Uncontrolled before-and-after4 (3.5)2 (10.5)2 (2.1)
Sampling approach
Convenience22 (19.3)5 (26.3)18 (18.8)
Population-based87 (76.3)13 (68.4)74 (77.1)
 Administrative records45 (39.5)6 (31.6)39 (40.6)
 Household survey25 (21.9)5 (26.3)20 (20.8)
 School-based survey17 (14.9)2 (10.5)15 (15.6)
Unspecified5 (4.2)1 (5.3)4 (4.2)
  • *Combined total exceeds number of studies because some evaluated both decriminalisation and legal regulation.

  • †One global study and one multi-country European study including Belgium and Portugal.