Time looks at the process of estimating drug use in the U.S.:
At least, that’s what the numbers say. Though it’s been more than 30 years since Richard Nixon famously announced America’s “War on Drugs,” it’s hard to know exactly how far we are from victory, partly because the facts are so elusive: Who uses illegal drugs? Which drugs? How often? The answers come mainly from SAMHSA’s national survey, a complex and carefully worded questionnaire administered continually throughout the year. It is one of the government’s primary sources of statistical information on the use of illegal drugs by the U.S. population, but its data are far from perfect.
“The bottom line is, we learn about drug use by asking people about their behaviors,” says Dr. Wilson Compton, director of the Division of Epidemiology Services and Prevention Research at the National Institute on Drug Abuse. “But because it’s survey research, there are multiple ways it can be improved.”