Exaggerated Job Woes Among Drug Users Used to Justify Tests, Study Says
BRENDA C. COLEMAN
Nov. 28, 1990
CHICAGO (AP) _ Claims about accident rates and performance problems used to justify pre- employment drug screening may be exaggerated, say medical researchers who studied thousands of postal workers.
The study didn't distinguish between occasional drug users and chronic abusers, who almost certainly would exhibit problems at higher rates, said a drug-abuse specialist not involved in the study.
''Drug users have been reported to be involved in 200 percent to 300 percent more industrial accidents, to sustain 400 percent more compensable injuries and to use 1,500 percent more sick leave,'' the researchers said.
But the study's findings suggest many such estimates used to justify pre- employment drug screening have been exaggerated, the researchers reported in Wednesday's Journal of the American Medical Association.
''We found that those with marijuana-positive urine samples have 55 percent more industrial accidents, 85 percent more injuries and a 78 percent increase in absenteeism,'' the researchers wrote.
For those with cocaine-positive urine samples, there was a 145 percent increase in absenteeism and an 85 percent increase in injuries, they said.
The researchers cited as examples of exaggerated accidents rates a 1986 manual from the U.S. Office of Personnel Management and articles in the journal Psychiatry Letter and the American Psychologist.
Peter Bensinger, a consultant on workplace drug and alcohol abuse, wrote one of the articles. He said he stands by his figures.
''We have clients who had great reductions in absenteeism, accidents with drug testing,'' Bensinger said.
Vice President Dan Quayle wrote the American Psychologist article in 1983, when he was a senator.
The lead researcher for the AMA journal study was Dr. Craig Zwerling, former medical director at the U.S. Postal Service in Boston and now with the University of Iowa College of Medicine at Iowa City.
He and his colleagues performed urine drug tests on almost 5,000 job applicants in Boston for positions of letter carrier, postal clerk, computer- forwarding system clerk and maintenance worker, including skilled technical worker.
The study's authors tracked the new hires between 1986 and 1989 to compile data for their report.
The marijuana test was sensitive for up to four weeks after use; the test for cocaine was sensitive up to 72 hours after use. Positive tests were confirmed, and only confirmed tests were reported.
Of the 2,537 new hires, 2,229, or 87.9 percent, tested negative; 198, or 7.8 percent, were confirmed positive for marijuana; 55, or 2.2 percent, confirmed positive for cocaine; and 55, or 2.2 percent confirmed positive for other ''non-therapeutic'' drugs or multiple drugs, the study found.
But nothing in their protocol distinguished the occasional user from the chronic abuser, said an editorial accompanying the study.
''Postal employees in the sample were classified as drug-involved solely on the basis of a single pre-employment urine test,'' said Eric D. Wish of the Center for the Prevention and Control of Substance Abuse at the University of Maryland in College
Wish said if the researchers could have differentiated between employees with chronic abuse problems from those who were infrequent users, the observed differences in job performance would have been larger.
Regardless, he said, the overall rate of drug abuse was small - 12 percent, two-thirds of which was marijuana use. Such a rate is dwarfed by the 50 percent to 60 percent rates of abuse among people arrested for drug and non- drug crimes, he said.
Wish suggested that society may benefit more by investing resources in testing and treating drug abusers coming through the criminal justice system than in finding the comparatively small number of mostly marijuana users in ''the primarily law-abiding employee populations.''