The number of workers testing positive for drug use dropped last year but not necessarily because fewer people are getting high, a new survey of large American corporations shows.
The findings released Thursday show companies are using better testing methods to weed out false positives. Also, as random drug testing has increased, a greater percentage of non-abusers is tested.
Positive tests declined to 1.9 percent of workers last year, compared with 2.5 percent in 1993, the American Management Association said. Positive tests among job applicants declined to 3.8 percent, from 4.5 percent.
The survey marked the fourth time in the past five years that positive test results have declined.
It was conducted this March and April among 1,151 companies that did tests on about 745,000 workers or applicants during 1994. The survey has a margin of error of plus-or-minus 2.5 percent.
"It's tempting to say there is lower drug use, but, as always in this field, things are not as simple as they seem," said Eric Greenberg, the association's director of management studies.
For one thing, the percentage of workers randomly tested went up last year because of new federal regulations requiring expanded tests of workers in transportation-related jobs.
"Any time you expand testing of people to include more people who are absent suspicion you're going to drive test-positive rates down," said Greenberg.
This boost in testing occurred even as the percentage of companies performing drug tests of any kind has remained relatively stable for three years at about 77 percent.
A more dramatic change came in how the tests were interpreted.
Seventy-six percent of the companies that did tests as of April employed a medical review officer who analyzes all findings, judges them against the worker's medical profile and then gives the results to the employer. That's up from 48 percent in 1994.
"These medical review officers offer significant protection to employees against, not only false positives, but true positives with a legitimate medical explanation," said Greenberg.
That protection is critical since positive tests bring swift punishment: 22 percent of companies now immediately dismiss those who test positive, while 21 percent impose suspensions, probations or other disciplinary action.
The survey also showed the number of companies that have drug education programs declined slightly to 47 percent as of this April, compared with 50 percent last year. Likewise the number of companies offering their supervisors training to spot drug abuse went down to 48 percent from 54 percent.
"If cost cutting is the rationale for elimination of such programs, the decision may prove penny-wise but pound foolish," the study report said, because companies with anti-drug programs consistently report lower test-positive rates.