Does Performing Preplacement Workplace Hair Drug Testing Influence US Department of Transportation Random and Postaccident Urine Drug Test Positivity Rates?

Background: Does performing pre-employment hair drug testing subsequently affect the prevalence of positive random and postaccident urine drug tests?

Methods: This cross-sectional study was designed to evaluate the prevalence of positive postaccident and random workplace urine drug tests for companies that perform pre-employment hair and urine drug testing to companies that only perform pre-employment urine drug testing.

Results: Fisher exact test of independence indicated no significant difference between pre-employment hair drug testing and overall US Department of Transportation random and postaccident urine drug test positivity rates.

Conclusions: The analysis failed to reject the null hypothesis, suggesting that pre-employment hair drug testing had no effect upon random and postaccident urine drug test positivity rates.