How Did the Government's Surveys Miss a Quadrupling in Meth Use?
In a story about the Combat Meth Act (which, among other things, will restrict access to cold and allergy medications that contain pseudoephedrine), The Washington Times mentions in passing that "law enforcement authorities said meth use nationwide has increased by as much as 300 percent in the past decade." In other words, the number of illicit methamphetamine users today is about four times what it was in the mid-1990s. Where is the evidence to support this claim?
Based on data from the National Household Survey on Drug Abuse (NHSDA), the Substance Abuse and Mental Health Services Administration estimated (see Table 9) that 0.4 percent of Americans 12 or older used methamphetamine for nonmedical purposes in 1995. The comparable figure for 2001 (see Table H.2) was 0.6 percent–an increase of 50 percent over six years. The following year, the NHSDA was revamped and renamed the National Survey on Drug Use and Health (NSDUH), so numbers from 2002 and later are not comparable to earlier numbers. (The new methodology was designed to increase respondents' candor, and there was an across-the-board increase in reported drug use.) But the NSDUH numbers can be compared to each other, and past-year meth use in that survey went from 0.7 percent in 2001 to 0.6 percent in 2004.
It's true these surveys cover only 98 percent or so of the population, and some of those who are missed, such as people living on the streets or behind bars, may be especially prone to illegal drug use. (Then again, the surveys also leave out people in the armed forces, where rates of illegal drug use may be lower than average.) And I realize people may not be completely honest in reporting their own illegal drug use, even when they're assured of confidentiality. But unless the dramatic increase in meth use claimed by the "law enforcement authorities" mentioned in The Washington Times has been limited to populations not sampled by the surveys and/or users' reluctance to admit meth use has been rising at the same rate as meth use itself, a quadrupling in consumption ought to be reflected in the survey data.
Instead, it looks like meth use went up in the late '90s by about one-sixth as much as "law enforcement authorities" claim and has remained pretty much flat since then. If these surveys are so inaccurate that they've missed more than 80 percent of a 300 percent increase, why does the government continue to rely on them (except when it comes to whipping up hysteria about the "meth epidemic")?