Did the industry miss 19,000 drug testing positives? DISA performed 700,000 short term-only tests from 2024 to 2025.
Those tests identified 8,820 positives. If those tests were conducted with dual methodologies, historical positivity rates project an additional 19,000 positive tests could be identified.
Safety-sensitive employers need drug testing programs to identify risk before it reaches the job site. Historical positivity data from DISA shows the strongest programs use both short-term and long-term methods, pairing urine with hair testing to give owners a broader view of workforce risk. Short-term testing helps identify recent or infrequent use and captures additional substances not included in some long-term panels. Long-term hair testing helps identify lifestyle users, including cases in which temporary abstinence may allow a donor to pass a short-term test.
Programs using dual methodologies identified 214% more positive tests than shortterm ones from 2024 to 2025. Short-term standalone testing had a 1.26% positivity rate, while dual-methodology testing using urine and hair had a 3.96% positivity rate. For a safety sensitive site that completes 1,000 drug tests, that difference represents a safety risk of 28 potentially impaired workers going undetected.
The longer detection window is key. When using only short-term drug testing, marijuana is detected five times more frequently than cocaine. With long-term drug testing, cocaine is detected nine times more often than shortterm testing alone and shockingly reports more positive tests than marijuana. It doesn’t stop there; hair testing detects amphetamines and opioids three to five times more often than shortterm testing alone.
Dual-methodology testing also supports deterrence. Programs using both hair and urine testing saw 30% lower short-term test positivity than programs using only short-term testing. Donors who know they will face both recentuse and long-window detection are less likely to attempt temporary abstinence or enter the process while carrying higher risk.
DISA’s data reinforces why leveraging both methods matter. Long-term methodologies alone can’t be the sole solution without risking recently impaired workers on-site. Analyzing data for the last 100,000 workers that completed a urine and hair test on the same day, the longterm methodology would miss one out of every 10 positives detected by short-term methods.
Additionally, short-term programs include expanded panels that detect drugs not included on a hair testing panel. While the additional substances tested are detected less often, they still create risk and add up to more positives than a recognized threat like opiates.
Short-term testing remains essential for post-accident and reasonable-suspicion testing because of the focus on recent use and potential current impairment. For contractors that also participate in the DISA Contractor Consortium, urine testing helps eligible workers move across DISA’s network of 420+ participating owner sites with less duplicate testing and less delay.
Shannon Shoemaker, chief revenue officer at Psychemedics, agreed, saying "These findings closely mirror what Psychemedics has consistently seen across millions of hair tests and multiple independent workforce studies over the years. Long-window detection matters, especially in safety-sensitive industries."
The best safety practice in safety-sensitive industries is dual methodologies, not one method instead of the other. Long-term testing detects more lifestyle usage and increases deterrence. Short-term testing strengthens recent-use detection, expands panel coverage and supports workforce mobility. Together, they create a more complete safety standard for safety-sensitive worksites.
For more information, visit disa.com/dual.
