"Substance use disorders (SUDs) are characterized by impairment caused by the recurrent use of alcohol or other drugs (or both), including health problems, disability, and failure to meet major responsibilities at work, school, or home. The 2021 NSDUH included a series of questions to estimate the percentage of the population aged 12 or older who had at least one SUD in the past 12 months (subsequently referred to as “an SUD” or “a past year SUD”). The SUD questions assess the presence of an SUD in the past 12 months based on criteria specified in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5).^61,62 Respondents were asked SUD questions for any alcohol or drugs they used in the 12 months prior to the survey. Drugs include marijuana, cocaine (including crack), heroin, hallucinogens, inhalants, methamphetamine, and any use of prescription stimulants, tranquilizers or sedatives (e.g., benzodiazepines), and pain relievers.¹⁸ Unlike in the section on Illicit Drug Use in the Past Year, the DSM-5 SUD criteria for prescription drugs apply to people who used but did not misuse prescription drugs in the past year, in addition to people who misused them.

"A Clinical Validation Study (CVS) was conducted in early 2020 to assess NSDUH SUD questions that were revised to be consistent with the DSM-5 criteria discussed as follows.⁶³ For the 2021 NSDUH, the SUD questions from the CVS replaced the SUD questions in the 2020 questionnaire. Also beginning in 2021, NSDUH respondents who reported any use of prescription psychotherapeutic drugs (i.e., pain relievers, tranquilizers, stimulants, or sedatives) in the past year (i.e., not just misuse of prescription drugs) were asked the respective SUD questions for that category of prescription drugs.

"DSM-5 includes the following SUD criteria (as measured in the 2021 NSDUH):

"1. The substance is often taken in larger amounts or over a longer period than intended.

"2. There is a persistent desire or unsuccessful efforts to cut down or control substance use.

"3. A great deal of time is spent in activities necessary to obtain the substance, use the substance, or recover from its effects.

"4. There is a craving, or a strong desire or urge, to use the substance.

"5. There is recurrent substance use resulting in a failure to fulfill major role obligations at work, school, or home.

"6. There is continued substance use despite having persistent or recurrent social or interpersonal problems caused by or exacerbated by the effects of the substance.

"7. Important social, occupational, or recreational activities are given up or reduced because of substance use.

"8. There is recurrent substance use in situations in which it is physically hazardous.

"9. Substance use is continued despite knowledge of having a persistent or recurrent physical or psychological problem that is likely to have been caused or exacerbated by the substance.

"10. There is a need for markedly increased amounts of the substance to achieve intoxication or the desired effect, or markedly diminished effect with continued use of the same amount of the substance (i.e., tolerance).

"11. There are two components of withdrawal symptoms, either of which meet the overall criterion for withdrawal symptoms:
"a. There is a required number of withdrawal symptoms that occur when substance use is cut back or stopped following a period of prolonged use.⁶⁴
"b. The substance or a related substance is used to get over or avoid withdrawal symptoms.⁶⁵"