Conclusions
- The Validity Study demonstrated that it is possible to collect urine and hair specimens with a high response rate from persons aged 12 to 25 in a household survey environment.
- The results of tests conducted on hair collected in this study could not be used to compare with self-reports because there were technical and statistical problems related to the hair tests and unresolved issues concerning the interpretation of the analytical results.
- Most youths aged 12 to 17 and young adults aged 18 to 25 reported their recent drug use accurately. However, there were some reporting differences in either direction—with some not reporting use and testing positive, and some reporting use and testing negative.
- Biological drug test results can be used as objective markers of drug use to verify selfreports. Researchers employing drug tests in epidemiological studies must be knowledgeable of the performance characteristics of analytical procedures used for the drug tests (e.g., capabilities of the test methods and validation of procedures used by the testing laboratory), as well as the pharmacology of the drugs tested to enable acceptable study design and correct interpretation of the drug test results in the different biological specimen matrices.