In 2003, 4.5% of all drug tests came back positive, up slightly from 2002’s 4.4% positive rate, but down from 4.6% in 2001. The percentage of positive drug tests are down significantly from 1988 when 13.6% of tests came back positive, according to Quest Diagnostics’ Drug Testing Index, based on more than 7.1 million drug tests performed by Quest Diagnostics from January to December 2003.
Driving the total higher in 2003 was a 44% increase in the use of amphetamines among the general US workforce testing positive. Overall, 0.49% of all positive drug tests showed levels of amphetamines, up from 0.34% in 2002 and 0.29% in 2001. Quest said growth in amphetamines use during this period represents the largest single-year surge in amphetamine use documented by the Drug Testing Index during the past five years.
In addition to growing amphetamines use, the incidence of positive drug tests attributed to opiates also grew noticeably in 2003, climbing by more than 25% from 2002 among general US workforce employees. During 2003, opiate positivity was 0.34% of all drug tests that look for opiates; in 2002, opiate positivity was 0.27%. Much like the increase in amphetamines, the 2003 swing in opiate positivity marked the single largest year-over-year change in opiate use among this group of workers since 1999. Quest attributed the surge in opiate use to the growing use of morphine.
Across all positive drug tests, the drug of choice was marijuana as the incidence of positive drug tests attributed to this drug reach was 2.96% in 2003. This was followed by:
- Cocaine – 0.74%
- Propoxyphene – 0.67%
- Benzodiazepines – 0.60%
- Barbiturates – 0.29%
- Methadone – 0.20%
- PCP – 0.03%.
A more complete copy of the analysis is available here .