Accuracy in workplace drug testing is not simply a technical concern. It reflects the reliability, fairness, and integrity of a company’s entire compliance process. According to SAMHSA’s Workplace Drug Testing Resources, employers should align their testing programs with current federal standards to ensure defensible results and consistent application across their organization.

Why Accuracy Is Essential

Accurate testing protects both employees and employers. A false negative can allow substance misuse to go undetected, while a false positive can unfairly impact a compliant employee. Federal materials emphasize that proper procedures, certified facilities, and thorough documentation are essential for maintaining accuracy and protecting due process. The guidance available through SAMHSA’s Employer Resources outlines how to implement these safeguards within a workplace policy.

Key Factors That Influence Accuracy

Collection Procedures and Chain of Custody

The accuracy of any urine drug test begins at the collection site. The Urine Specimen Collection Handbook outlines the step-by-step procedures required to preserve specimen integrity, including donor identification, temperature checks, and secure sealing of the sample. Every step is documented on the Custody and Control Form to establish a defensible chain of custody.

Certified Testing Facilities and Laboratory Protocols

Federal regulations require that all testing for regulated programs be conducted through HHS-certified laboratories or instrumented initial test facilities. The Mandatory Guidelines for Federal Workplace Drug Testing Programs establish the technical and quality assurance standards for these facilities. Employers can confirm certification by consulting the HHS-Certified Laboratory List available through SAMHSA.

Specimen Validity and Adulteration Controls

Specimen validity testing helps ensure that the sample has not been tampered with or substituted. The collection handbook and federal guidelines describe the use of validity checks to detect dilution, substitution, or adulteration. These steps prevent inaccurate readings and ensure that laboratory results are trustworthy.

Documentation and Oversight

Accurate programs depend on consistent documentation and clear role definitions for everyone involved, from the collector to the Medical Review Officer. The Urine Collection Site Manual and the MRO Guidance Manual provide direction for training, requalification, and case handling. Proper documentation of each custody transfer, review, and test result strengthens the defensibility of every report.

Evaluating Vendors and Service Providers

When selecting a test provider, employers should confirm that the laboratory appears on the federal certification list and follows the required procedures. Questions to ask include:

• How closely do your collection sites follow the procedures in the Urine Specimen Collection Handbook?

• Are your cutoff levels aligned with the thresholds defined in the Mandatory Guidelines?

• What validity checks are performed to detect specimen tampering or adulteration?

• How are results stored and transmitted to maintain compliance with federal recordkeeping requirements?

These questions help verify whether a provider’s process aligns with national standards and ensures that test results are legally defensible if challenged.

Maintaining Compliance Over Time

Compliance is an ongoing responsibility. Employers should routinely review their drug testing policies and compare them against the latest federal guidance. Conducting regular audits, retraining staff, and maintaining documentation consistent with SAMHSA’s Employer Resources are key elements of a sustainable program. Employers should also monitor updates to official manuals and guidelines to stay current with regulatory changes.

Conclusion

Reliable results come from structured procedures, certified facilities, and disciplined oversight. By following the processes detailed in SAMHSA and HHS publications, employers can create drug testing programs that are accurate, defensible, and aligned with federal best practices.