Drug testing in the workplace--are methods legally defensible? A survey of experts, arbitrators, and testing laboratories.

Urinalysis results are increasingly being used by employers to detect use of prohibited substances in the workplace. Actions taken on the basis of positive urinalysis results can have a significant effect on employees' lives and careers, and may face legal challenge. Important aspects of urinalysis are choice of analytical methods and their legal defensibility. Medical directors are frequently required to select testing laboratories, but have had few data correlating analytical methods with legal defensibility. To evaluate the legal defensibility of the methods used for drug testing, we conducted a survey of technical experts, testing laboratories, and arbitrators. Experts reported wide differences in the legal defensibility of methods rated. Arbitrators had considerable experience in drug use cases and understood the critical role of urinalysis results, but were unable to distinguish legal defensibility of analytical methods. Commercial laboratory practice in urinalysis varies widely among laboratories. An objective of this article is to provide company medical directors with information that will enable them to make informed decisions when choosing urinalysis laboratories and methods.