Test Negative Sci. Amer. Mar, 1990

Test Negative A look at the "evidence" justifying illicit-drug tests

SCIENCE and the CITIZEN

SCIENTIFIC AMERICAN March 1990, p. 18

John Horgan

More than eight million working Americans had their urine tested for
illegal drugs in 1989, and as many as 15 million will undergo such testing
this year, according to the National Institute on Drug Abuse (NIDA). The
fraction of companies that subject employees or job applicants to testing
has jumped from 21 percent in 1986 to more than 50 percent last year,
according to the American Management Association. The trend seems likely
to continue: a majority of the respondents to a recent Gallup poll favored
random drug testing of all workers.

What underlies the broad acceptance of a practice that conservative
Supreme Court Justice Antonin Scalia has called a "needless indignity?"
One factor may be the alarming statistics cited by testing advocates to
demonstrate the high costs of drug abuse. Examination of some of these
claims suggests that they do not always accurately reflect the research on
which they are based. In fact, some of the data could be used to "prove"
that drug use has negligible or even beneficial effects. Consider these
examples.

Last year President George Bush declared that "drug abuse among
American workers costs businesses anywhere from $60 billion to $100 billion
a year in lost productivity, absenteeism, drug-related accidents, medical
claims and theft." Variants of this statistic abound in discussions about
drug abuse and are commonly repeated without qualification by the media.
Yet all such claims derive from a single study, one that "was based upon
assumptions which need additional validation," according to an assessment
last year by NIDA, the chief federal agency sponsoring research on
substance abuse.

The study grew out of a survey of some 3,700 households by the
Research Triangle Institute (RTI) in 1982. The RTI group found that the
average reported income of households with at least one person who admitted
to having ever used marijuana daily (20 days or more in a 30-day period)
was 28 percent lower than the average reported income of otherwise similar
households. The RTI researchers defined that difference in income as
"loss due to marijuana use"; the total loss, when extrapolated to the
general population, came to $26 billion. The researchers then added on the
estimated costs of drug-related crime, health problems and accidents to
arrive at a grand total of $47 billion for "costs to society of drug
abuse." This figure-- "adjusted" to account for inflation and population
increase -- represents the basis of Bush's statement, according to Henrick
J. Harwood, who headed the RTI study and is now in the White House
drug-policy office.

The RTI survey included questions on current drug use (at least
once within the past month). Yet according to Harwood there was no
significant difference between the income of households with current users
of any illegal drug -- including marijuana, cocaine and heroin -- and the
income of otherwise similar households. Does this mean that current use of
even hard drugs -- as opposed to perhaps a single marijuana binge in the
distant past -- does not lead to any "loss"? "You would be on safe ground
saying that," Harwood replies.

Officials of the U.S. Chamber of Commerce have testified before
Congress and at national conferences on drug abuse that employees who use
drugs are "3.6 times more likely to injure themselves or another person in
a workplace accident....[and] five times more likely to file a workers'
compensation claim." The pharmaceutical giant Hoffmann-La Roche, which is
leading an antidrug campaign among businesses (and has a big share of the
drug-testing market), also promulgates this claim in "educational"
literature.

In fact, the study on which the claim is based has "nothing to do
with [illegal] drug users," according to a 1988 article in the University
of Kansas Law Review by John P. Morgan of the City University of New York
Medical School. Morgan, an authority on drug testing, has traced the
Chamber of Commerce claim to an informal study by the Firestone Tire and
Rubber Company of employees undergoing treatment for alcholism.

In an interview with SCIENTIFIC AMERICAN, J. Michael Walsh, who
heads NIDA's applied research division and is a strong supporter of
workplace testing, singled out two studies that he said showed drug users
are more likely to cause accidents, miss work and use health benefits. The
studies were done at two utilities: the Utah Power and Light Company and
the Georgia Power Company. The 12 workers in Utah and the 116 in Georgia
who served as the primary research subjects were tested "for cause": they
had either been involved in accidents, exhibited other "problem" behavior
(commonly, high absenteeism) or submitted to treatment for alcoholism or
drug abuse. Critics point out that it should not be terribly surprising if
these subjects exhibited the cited traits at a higher-than-average rate.

What may be surprising is that, according to a report published by
NIDA last year, Utah Power and Light actually "spent $215 per employee per
year less on the drug abusers in health insurance benefits than on the
control group." Those who tested positive at Georgia Power had a higher
promotion rate than the company average. Moreover, Georgia workers testing
positive only for marijuana (about 35 percent of all the positives)
exhibited absenteeism some 30 percent lower than average. Nationwide,
Morgan says, marijuana accounts for up to 90 percent of all positive
findings, both because it is by far the most widely used illegal drug and
because it persists in urine for up to a month (compared with two days for
most other drugs).

Perhaps the study most publicized of late by testing proponents
involves employees of the U.S. Postal Service. The service tested 4,396
new hirees in 1987 and 1988 and -- keeping the test results confidential --
tracked the performance of positives (9 percent of the total) and
negatives. By last September, the service reported, 15.4 percent of the
positives and 10.5 of the negatives had been fired: the positives had also
taken an average of six more sick days a year.

This study may be distorted by more subtle biases --related to
race, age or gender --than those displayed by the utility studies,
according to Theodore H. Rosen, a psychologist and a consultant on drug
testing. Indeed, Jacques L. Normand, who headed the study, acknowledges
that minority postal workers tested positive at a much higher rate than
nonminority workers and that previous studies have shown minorities to have
higher absenteeism.

Morgan points out, moreover, that the Postal Service study (like
all those cited above) has not been published in a peer-reviewed journal.
In fact, he says, only one study comparing the work of drug-test positives
and negatives has passed peer review. Last year, in the JOURNAL OF GENERAL
INTERNAL MEDICINE, David C. Parish of the Mercer University School of
Medicine in Georgia reported on a study of 180 hospital employees, 22 of
whom had tested positive after being hired. Parish examined supervisor
evaluations and other indexes and found "no difference between
drug-positive and drug-negative employees" at the end of one year. He
noted, however, that 11 of the negatives had been fired during that period
and none of the positives.

Proponents of testing often imply that drug use among workers is
growing. A Hoffman-La Roche brochure, for example, quotes Walsh
pronouncing that "the problem of drug abuse has become so widespread in
America that every company must assume that its employees will eventually
be faced with a substance abuse problem." Yet in 1989 NIDA reported that
illegal drug use has been decreasing for 10 years and that the decline has
accelerated over the last five years. From 1985 to 1988 the number of
current users (at least once in the last month) of marijuana and cocaine
dropped by 33 and 50 percent, respectively.

To be sure, a subset of this group of current users is increasing:
NIDA estimated that from 1985 to 1988 the number of people using cocaine at
least once a week rose from 647,000 to 862,000 and daily users increased
from 246,000 to 292,000. NIDA found that addiction to cocaine (including
"crack") is particularly severe among the unemployed -- who are beyond the
reach of workplace testing.

Clearly, the U.S. has a drug-abuse problem. Could it be that
neither indiscriminate testing of workers -- which could cost upward of
$500 million this year -- nor the dissemination of alarmist information by
testing advocates is helping to resolve that problem?

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