Prevalence of marijuana use in adults in the USA, NHANES 2005–2018
| 2005–2006 | 2007–2008 | 2009–2010 | 2011–2012 | 2013–2014 | 2015–2016 | 2017–2018 | P | ||||||||
| Total N | Prevalence % (95% CI) | Total N | Prevalence % (95% CI) | Total N | Prevalence % (95% CI) | Total N | Prevalence % (95% CI) | Total N | Prevalence % (95% CI) | Total N | Prevalence % (95% CI) | Total N | Prevalence % (95% CI) | ||
| Lifetime use | 2922 | 61.5 (57.2 to 65.7) | 3255 | 60.5 (57.2 to 63.7) | 3739 | 57.2 (53.0 to 61.3) | 3333 | 59.9 (56.0 to 63.6) | 3690 | 59.2 (55.6 to 62.7) | 3422 | 57.3 (53.1 to 61.5) | 3199 | 60.9 (57.9 to 63.7) | 0.53 |
| Age <18 at first used | 1617 | 59.6 (56.7 to 62.7) | 1799 | 60.7 (58.0 to 63.5) | 1937 | 62.7 (59.0 to 66.4) | 1770 | 60.1 (56.0 to 64.0) | 1984 | 61.4 (58.8 to 63.9) | 1715 | 60.1 (56.5 to 63.7) | 1737 | 61.8 (57.1 to 66.3) | 0.68 |
| Past-year use | 2922 | 19.1 (15.3 to 23.7) | 3255 | 19.1 (17.5 to 20.7) | 3739 | 20.6 (18.2 to 23.3) | 3333 | 22.4 (19.8 to 25.2) | 3690 | 22.3 (19.9 to 24.8) | 3422 | 24.9 (20.0 to 30.6) | 3199 | 29.1 (26.0 to 32.5) | <0.001 |
N denotes unweighted total number of participants in each category.
Prevalence percentage with 95% (CI), computed using 2-year MEC weights to provide estimates for the total US population, and age standardised to 2000 Census population.
P values test overall trend in prevalence estimates in each category.
MEC, mobile examination centre; NHANES, National Health and Nutrition Examination Survey.