The Quest Diagnostics Drug Testing Index reveals insights into patterns of drug use among the American workforce. Published annually since 1988, the Drug Testing Index examines positivity rates for workplace drugs tested by the company on behalf of employers. We publish these findings as a public service for government, employers, media, and the general public.

Key insights include:

• Marijuana positivity increased across nearly all employee testing categories

• Increases in post-accident positivity in the general U.S. workforce outpaced all other testing reasons, including pre-employment screening

• Positivity for heroin and cocaine decreased in urine testing in both employee testing categories

• Increases in specimens reported as invalid suggests more efforts by donors to “cheat the test”