Drug Testing At Work Is A Thing Of The Past, Study Finds According to a study conducted by Quest Diagnostics Inc (NYSE: DGX ), drug use among American employees, as measured by the percentage of employees who tested positive in urine drug tests, hit a 14-year high in 2018, reaching 4.4 percent. Cannabis continues to be the most popular substance, with 2.8 percent of all employees tested showing positive results. The news led addiction experts at the American Addiction Centers to wonder about the impact this might have on pre-employment drug testing in professionals. Seeking for an answer, they conducted an analysis of job postings on the popular website Glassdoor. They were trying to find out what types of jobs are most likely to include requirements for drug tests, and regular drug screening. Overall, remarkably few jobs disclose that they require drug testing before confirming employment, or during employment. On average, only 1.47 percent of job postings in the U.S. mention that they require pre-employment drug tests. See also: