Fig. 3
From: Positive drug test trends in fatally-injured drivers in the United States from 2007 to 2017
Trend in yearly prevalence in positive drug test among drivers who died within 1 h of crashing, by age. Cochran–Armitage tests were used to assess the statistical significance of changes in the percentage of drug involvement in fatally-injured drivers over time (16–20: Z = 8.5, p < 0.00; 21–44: Z = 20.5, p < 0.001; 45–64:Z = 13.4, p < 0.001; 65+: Z = 8.0, p < 0.001)