I am not concerned as it was voluntary. HOWEVER, what does it prove? They are looking for the effects of alcohol and drugs (including prescription) on drivers. So, if not on drugs, alcohol, have a history where you don't want your information out, they you take the $10 (swab) or $50 (blood). But, if you have been drinking or drugs, you say no fuking way I am volunteering for this test, so exactly what is the percentage of error, +- 100%. There is better work that can be done with federal grant money.