Interpretation of nail specimen analysis for substance use involves examining a laboratory report that details the presence or absence of specific drugs or their metabolites. The report typically indicates the detected substances, their corresponding concentrations, and established cutoff levels. A result exceeding the cutoff indicates a positive finding for that particular substance; a result below the cutoff is considered negative. For example, a report might show “Cocaine: 50 pg/mg (Positive)” if the detected concentration of cocaine is 50 picograms per milligram of nail sample, and the cutoff is, say, 20 pg/mg.
Analyzing nail test outcomes provides a retrospective window into substance use over several months, offering advantages over urine or blood tests with shorter detection windows. This extended detection period can be particularly valuable in monitoring long-term adherence to treatment programs or in situations where a more comprehensive history of substance use is required. Furthermore, nail testing is generally considered less susceptible to adulteration compared to urine testing, increasing the reliability of the results.