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2020 National Survey of Drug Use and Health (NSDUH) Releases

These reports and detailed tables present estimates from the 2020 National Survey on Drug Use and Health (NSDUH).

Highlights for 2020 National Survey on Drug Use and Health

2020 NSDUH Frequently Asked Questions

1. Why does SAMHSA caution against comparing 2020 estimates with prior years’ estimates?

  • The coronavirus disease 2019 (COVID-19) pandemic necessitated methodological changes in data collection. The COVID-19 pandemic could have affected both the true prevalence of a behavior (or mental health issue) and the behavior’s measurement through the necessitated methodological changes. The primary methodological changes were (1) virtually no data collection from mid-March through September 2020, (2) introduction of web data collection in October 2020 with very limited in-person data collection, and (3) questionnaire changes beginning in October 2020. These changes could result in data collection mode effects or other effects on the estimates. Because these changes in data collection coincided with the spread of the COVID-19 pandemic and any related behavioral or mental health changes, we cannot fully separate the effects of methodological changes from true changes in the outcomes.
  • Cautioning against comparisons does not necessarily mean the data are not comparable. For most estimates, comparability is unknown.

2. Are some 2020 estimates clearly not comparable with those from prior years? Why did substance use disorder (SUD) estimates, for example, change dramatically from 2019?

  • First, why did SUD estimates change dramatically?
    • The criteria used to categorize SUD among NSDUH respondents changed from the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) to the fifth edition (DSM-5), resulting in some differences in who is classified as having an SUD. For this reason alone, the DSM-5 SUD estimates from 2020 are not comparable with the DSM-IV SUD estimates from prior years.
    • The COVID-19 pandemic and resulting societal upheavals may have changed substance availability, substance use behavior, and/or treatment utilization. Therefore, part of the observed change may have been true, but true change does not affect comparability.
    • Methodological changes in Quarter 4 (October to December) data collection may have contributed to the observed changes in SUD estimates, but the impact of methodological changes is likely to be minor relative to the change from DSM-IV to DSM-5 SUD criteria.
  • Second, what other 2020 estimates are clearly not comparable with those from prior years?
    • Questions about a respondent’s last marijuana purchase are not comparable because they now exclude respondents who purchased marijuana from a store or a dispensary. Also, some questions about the last purchase or trade of marijuana are not comparable because of question format changes and the addition of a response option for “some other form.”
    • Kratom was a new item in the 2019 NSDUH, and originally, missing values were not imputed. The 2020 kratom variable was imputed for missing values and is considered not comparable with the original 2019 variable. (An imputed version of the kratom variable for 2019 is now available, but comparability is unknown because of methodological changes discussed earlier.)
    • Other wording changes for self-administration, clarified instructions, and minor logic changes are less likely to render responses not comparable.

3. The DSM-IV and DSM-5 estimates are so different. Which set is right?

  • Both are “right” relative to the diagnostic criteria in their respective DSM editions. Between DSM-IV and DSM-5, the SUD criteria were changed, resulting in differences in the groups of people who are classified as having an SUD.
  • Under DSM-IV, a NSDUH respondent is classified as having an SUD if they meet at least 1 of 4 criteria of substance abuse (these criteria focus on behaviors that reflect consequences of misuse of the substance) and/or at least 3 of 7 criteria of substance dependence (these criteria focus on behaviors that reflect indications that one has become addicted to or dependent upon the substance). The DSM-5 criteria do not make distinctions between symptoms of substance abuse and those of substance dependence. Instead, a DSM-5 SUD classification requires that at least 2 of 11 criteria be met.
  • In addition to the way the criteria are grouped, there are two significant differences between the DSM-IV SUD criteria and the DSM-5 SUD criteria. Ten of the DSM-5 criteria correspond to DSM-IV criteria for either substance abuse or substance dependence. One criterion of DSM-IV substance abuse (recurrent substance-related legal problems) is not part of the DSM-5 SUD criteria. Recurrent substance-related legal problems are a symptom that reflects severe disorder, a DSM-IV criterion that was not frequently met. One new criterion (craving or a strong desire to use the substance) has been added to DSM-5 that was not present in the DSM-IV SUD criteria. Craving is a commonly experienced symptom for several classes of substances such as opioids and sedatives.

4. In 2020, were the data collected in Quarter 1 (January to March) different from the data collected in Quarter 4?

  • Quarter 1 data were collected much like the data in 2019 were collected, with all household screenings and individual interviews conducted in person. Quarter 4 data are different because of the following:
  • The COVID-19 pandemic and related mandates could have changed people’s behavior and mental health.
  • Quarter 4 data collection methodology, data processing, and data collection outcomes changed as follows:
    • Web-based data collection was introduced because many areas could not be accessed in person.
    • Screening and overall response rates were considerably lower for web-based data collection.
    • Youth interview response rates via the web declined because of the required procedures for obtaining parental permission.
    • A nontrivial number of web interviews were not completed, resulting in more missing responses to questions later in the questionnaire.
    • Web respondents tended to have higher levels of educational attainment, on average, than in-person respondents and the general population. The weighting procedures incorporated educational attainment into the weight poststratification to correct the imbalance.
    • New questions were introduced in Quarter 4 for telehealth services, youth suicidality, and issues related to the COVID-19 pandemic.

5. What impact did adding a new data collection mode (web) have on the estimates?

  • Because the introduction of the web mode to NSDUH coincided with the effects of the COVID-19 pandemic on people’s behavior and mental health, it currently is not possible to quantify the effects of the web mode on the estimates.

6. The number of completed interviews for the 2020 NSDUH is much lower than it was in previous years. What impact does a smaller sample size have on the estimates?

  • The 2020 NSDUH sample has almost no data from mid-March through September. If the COVID-19 pandemic altered people’s behavior and mental health during this period of changing infection rates, lockdowns, and other societal changes, the data from the other months will not represent the missing quarters appropriately. The sample is representative of January to March and October to December combined but is not representative of the entire year in which people experienced changes in virtually every aspect of life.
  • The sample for each calendar quarter follows the same national/state design as each full-year sample, and the weights for sample records are adjusted so that the sums are consistent with known national totals. For these reasons, the combined sample from Quarters 1 and 4 is representative in terms of geography (total U.S. and states) and demographic characteristics, even though it is smaller than prior years’ samples.
  • In general, the larger the sample, the more precise the estimates. Having a smaller national sample in 2020 means that many national estimates are not quite as precise as estimates from prior years, although the precision for national estimates is considered more than adequate.
  • The greater challenge of having a smaller sample is producing sufficiently precise estimates for small subpopulations and for rare behaviors. If an estimate is deemed insufficiently precise because the sample is too small, the estimate will be suppressed in tables and reports. More estimates were suppressed in 2020 than in prior years.

7. Is SAMHSA still planning to release state-level estimates using 2020 NSDUH data?

  • Yes. SAMHSA will release state and substate estimates using small area estimation techniques for most estimates.

8. If SAMHSA is asking us to exercise caution when comparing 2020 data with prior years, why then can the 2020 data be combined with prior year data to generate the state-level estimates?

  • At issue here are two separate but seemingly similar concepts; comparing and combining. We ask that people use caution when comparing 2020 with any single prior year since there were changes in how we collected the data (i.e. going from solely in-person interviewing to a combination of web-based and in-person interviewing). For example, suppose we see an apparent increase from 2019 to 2020 in the percentage of major depressive episodes (MDEs) in a particular group. It may be that the difference we are seeing reflects an actual change in that population regarding MDE. Or it may be that simply asking the questions by a different method (e.g. web vs in-person) influenced the way respondents answered the depression questions, and that there is no actual increase in MDE in that group. At this point, there is no way for us to tell which of these things happened. Therefore, we ask that people use caution when making that comparison.
  • But when we are talking about combining the data, that is a different concept. Combining data from multiple years is necessary to provide enough data to calculate precise estimates at the state and sub-state level. So, back to our MDE example, the methods we used to collect that data have changed, but the scales we use to assess MDE have not. Also, since we are interested in the average across those years, any effect that the method change may have had will be lessened to a negligible level, and the resulting estimate will still be valid.
  • One measure, i.e. substance use disorder, not only was subject to the same methodology change as described above, but also was subject to a change in the scales that we use to assess them (going from DSM-IV criteria to DSM-5 criteria). Because of this change, it would not be valid to combine the data to calculate estimates for substance use disorder (or any other estimates that are reliant on substance use disorder). And in fact, these estimates were not calculated and will not be part of the state and sub-state report.

    Please direct any questions regarding the data included in this report to CBHSQRequest@samhsa.hhs.gov.

    Read the entire 2020 NSDUH report, highlights from it or frequently asked questions about it. People searching for treatment for mental or substance use disorders can find treatment by visiting findtreatment.samhsa.gov or by calling SAMHSA’s National Helpline, 1-800-662-HELP (4357) .Reporters with questions should send inquiries to media@samhsa.hhs.gov.

Annual National Report

Key Substance Use and Mental Health Indicators in the United States

NSDUH’s latest annual report focuses on substance use and mental health in the United States based on NSDUH data from 2020 and earlier years. The annual report presents estimates that meet the criteria for statistical precision and facilitate stable examination of trends over time to study changes in society and emerging issues. The 2020 Key Substance Use and Mental Health Indicators report summarizes the following:

  • Substance use (alcohol, tobacco, marijuana, cocaine, heroin, hallucinogens, and inhalants, as well as the misuse of opioids, prescription pain relievers, tranquilizers or sedatives, stimulants, and benzodiazepines)
  • Initiation of substance use
  • Perceived risk from substance use
  • Substance use disorders
  • Any mental illness, serious mental illness, and major depressive episode
  • Suicidal thoughts, plans, and non-fatal attempts for adults aged 18 or older
  • Substance use treatment and mental health service use

View the slides based on the Annual National Report: Key Substance Use and Mental Health Indicators in the United States (PDF | PPT).

Detailed Tables

The 2020 NSDUH Detailed Tables present national estimates of substance use and mental health. Tables in different sections present data from 2019 and 2020 and data from 2002 to 2020. These tables present information for differences across population subgroups in 2020. In addition, they present information for youths aged 12 to 17 and adults aged 18 or older (separately and combined) on drug, alcohol, and tobacco use, as well as substance use disorder (SUD), risk and availability of substance use, treatment, health topics, and the perceived effects of the Coronavirus Disease 2019 (COVID-19). Please refer to Chapters 3 and 4 of the Methodological Summary and Definitions report for more information.

Sections of the 2020 Detailed Tables:

Please refer to the related README file for instructions on how to use the Table of Contents and download files for faster viewing.

Methodology

The 2020 Methodological Summary and Definitions report summarizes the 2020 NSDUH methods and other supporting information relevant to estimates of substance use and mental health issues. This report accompanies the annual detailed tables and provides information on key definitions for many of the measures and terms used in these detailed tables and in other 2020 NSDUH documents, along with further analytic details on these measures and the survey. The report is organized into six chapters:

  • Chapter 1 is an introduction to the report.
  • Chapter 2 describes the survey, including information about the sample design; data collection procedures; and key aspects of data processing, such as development of analysis weights.
  • Chapter 3 presents technical details on the statistical methods and measurement, such as suppression criteria for unreliable estimates, statistical testing procedures, and issues for selected substance use and mental health measures.
  • Chapter 4 covers special topics related to prescription psychotherapeutic drugs.
  • Chapter 5 describes other sources of data on substance use and mental health issues, including data sources for populations outside the NSDUH target population.
  • Chapter 6 covers Special Methodological Issues for the 2020 NSDUH.
  • Appendix A is a glossary that covers key definitions for use as a resource with the 2020 NSDUH reports and detailed tables.
  • Appendix B provides a list of contributors to the report.