Attachments A, L, S

2020 NSDUH, Supporting Statement
Attachment A – Sample Design Report

SAMPLE DESIGN
2020 National Survey on Drug Use and Health Sample Design
The 2020 National Survey on Drug Use and Health (NSDUH) is a continuation of a four-year
sample design which was introduced by the Center for Behavioral Health Statistics and Quality
(CBHSQ) in 2014. Similar to previous NSDUHs, the 2020 NSDUH sample design is a stratified,
multi-stage area probability design. The sample design provides for estimates by state in all 50
states and the District of Columbia (DC). As shown in Table 1, the main 2020 survey will have a
sample designed to yield 4,560 completed interviews in California; 3,300 completed interviews
each in Texas, New York, and Florida; 2,400 completed interviews each in Illinois,
Pennsylvania, Ohio, and Michigan; 1,500 completed interviews each in Georgia, North Carolina,
New Jersey, and Virginia; 967 completed interviews in Hawaii; and 960 completed interviews in
each of the remaining 37 states and DC. In addition, the sample will be expanded by 1,500
interviews in the first six months of the survey year to support the Clinical Validation Study
(CVS). Therefore, the total national target sample size for the 2020 NSDUH is 69,007 completed
interviews. The sample will be selected from 6,000 area segments which vary in size according
to state. For the 2020 NSDUH, each state’s main sample will be allocated to age groups as
follows: 25 percent 12 to 17, 25 percent 18 to 25, 15 percent 26 to 34, 20 percent 35 to 49, and
15 percent 50 or older. The CVS sample expansion will be allocated proportionally to age
groups.
Table 1. Sample Sizes and Projected Respondents by State and Age Group, 2020 NSDUH

State

Total
Population
CA
TX, NY, FL
IL, PA, OH,
MI
GA, NC, NJ,
VA
HI
Remaining
37 States and
DC
Q1 and Q2
Sample
Expansion
(CVS)

State
Sampling
Regions
(SSRs)

Segment
Size

No. of
Segments

15.833
13.75

6,000
288
240

Age
12–17

Age
18–25

Age
26–34

Age
35–49

Age
50+

Total
Age
12+

17,015
1,140
825

17,066
1,140
825

10,344
684
495

13,836
912
660

10,746
684
495

69,007
4,560
3,300

750
36
30

600

600

360

480

360

2,400

24

12.5

192

375
242

375
242

225
145

300
193

225
145

1,500
967

15
12

12.5
10.07

120
96

240

240

144

192

144

960

12

10

138

189

218

335

620

1,500

96

Beginning in 2014 and continuing with the 2020 NSDUH, the sample will be designed to yield a
minimum of 200 completed interviews in Kauai County, Hawaii over a three-year period. This

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will allow for Kauai County to be included as a separate entity in the production of substate
estimates that are produced biennially and typically based on three years of data. To achieve this
goal while maintaining precision at the state level, Kauai County will be treated separately from
the remainder of Hawaii for sample allocation and sample size management purposes. The
annual sample in Hawaii will consist of 67 completed interviews in Kauai and 900 completed
interviews in the remainder of the state, for a total of 967 completed interviews each year.
Finally, the 2020 design includes the selection of Census block groups at the second stage of
selection. This stage of selection was included beginning in 2014 to facilitate moving to an
address-based sample (ABS) design in the future, if desired. Compared to geocoding at the
Census block level, geocoding accuracy improves significantly at the Census block group level
in both rural and urban areas. Thus, in an ABS design, Census block groups would serve as
geographic clusters in areas with sufficient mailing address coverage. The selection of Census
tracts at the first stage of selection and Census block groups at the second stage has the potential
to reduce sampling variance by controlling the distribution of selected areas and reducing the
chance of selecting neighboring and possibly similar areas within tracts and block groups. In
addition, the merging of NSDUH data to external data sources for future analysis purposes is
simplified when sampled areas are contained within tract and block group boundaries to the
extent possible.
First, Second, and Third Stages of Selection: Census Tracts, Census Block Groups and
Segments
A coordinated sample for the period 2014-2017 was selected down to the area segment level as a
means of coordinating the overlap of sample areas from year to year. In anticipation of the next
decennial census data being unavailable, a large reserve sample was also selected and is
available for use in 2018 through 2020.
The “first level” of stratification within the coordinated design is states. The larger sample sizes
obtained at the state level along with small area estimation (SAE) techniques or direct estimation
techniques will enable the development of estimates for all states, for several demographic
subgroups within each state (e.g., age group and gender), for some Core Based Statistical Areas
(CBSAs), and for other small areas.
The “second level” of stratification within the coordinated design was defined as contiguous
geographic areas (groups of Census tracts) within each state. Within each state, state sampling
regions (SSRs) are of approximately equal size in terms of the population and allocated state
sample, except in Hawaii where Kauai County is its own SSR and the remainder of the state is
divided into equal-sized regions.
The design of the first stage of selection began with the construction of an area sample frame that
contained one record for each census tract in the United States. If necessary, census tracts were
aggregated until each tract had a minimum number of dwelling units. In California, Texas, New
York, Florida, Illinois, Pennsylvania, Ohio, Michigan, Georgia, North Carolina, New Jersey, and
Virginia, this minimum size requirement was 250 dwelling units in urban areas and 200 dwelling
units in rural areas. The basis for the differing minimum dwelling unit requirement in urban and

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rural areas is that it is more difficult to meet the requirement in rural areas, and 200 dwelling
units are sufficient to support one field test and two main study samples. In the remaining states
and DC, the number of completed interviews per sampled area is smaller and, therefore, fewer
dwelling units are needed. In these states, the minimum requirement was 150 dwelling units in
urban areas and 100 dwelling units in rural areas. After primary sampling units (PSUs; one or
more census tracts) were formed, a sample was selected within each SSR with probabilities
proportionate to a composite size measure and with minimum replacement. Additional implicit
stratification was achieved by sorting the first-stage sampling units by a CBSA/SES
(socioeconomic status) indicator 1 and by percent non-Hispanic white prior to selection.
For the second stage of selection, adjacent Census block groups were aggregated within selected
PSUs as necessary to meet the minimum dwelling unit requirements (150 or 250 dwelling units
in urban areas and 100 or 200 dwelling units in rural areas, according to state). After the
resulting secondary sampling units (SSUs; one or more census block groups) were formed, one
SSU was selected per sampled PSU with probability proportionate to a composite size measure.
For the third stage of sampling for the coordinated sample, each of the selected Census block
groups was partitioned into clusters of dwelling units by aggregating adjacent Census blocks.
Consistent with the terminology used in previous surveys, these geographic clusters of blocks are
referred to as segments. Segments were formed so that they contain the same minimum number
of dwelling units as the PSU (i.e., Census tracts) and SSU (i.e., Census block groups) to which
they belong. That is, area segments contain at least 150 or 250 dwelling units in urban areas and
100 or 200 dwelling units in rural areas according to state. Segments were constructed using
2010 Decennial Census data supplemented with 2013 population projections obtained from
outside sources. A sample dwelling unit in the survey refers to either a housing unit or a group
quarters listing unit such as a dormitory room or a shelter bed.
One segment was selected within each selected Census block group with probability
proportionate to a composite size measure. As mentioned previously, segments were formed so
that they will contain sufficient numbers of dwelling units to support one field test and two
annual survey samples. This allows half of the segments used in any given year’s main sample to
be used again in the following year as a means of improving the precision of measures of annual
change. This also allows for any special supplemental sample or field test that SAMHSA may
wish to conduct within the same segments.
A sample of 8 segments per SSR will be used for the 2020 survey year. These 8 segments will be
randomly assigned to quarters and to two panels within each quarter. The panels used in the 2020
survey will be designated as panels 7 and 8. Panel 7 segments have been used for the 2019
survey and will be used for the second time in the 2020 survey. The panel 8 segments will be
used for the 2020 and 2021 surveys. Dwelling units that were not selected for the 2019 survey
will be eligible for selection in the panel 7 segments in 2020.

1

Four categories are defined as: (1) CBSA/low SES, (2) CBSA /high SES, (3) Non CBSA /low SES, and
(4) Non-CBSA /high SES.

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Approximately one-fourth of the main sample of respondents will be collected from each
calendar quarter. 2 This design feature will help control the influence of seasonal variation on
drug use prevalence estimates and other important survey outcome measures of interest.
Fourth Stage of Selection: Listed Lines
Before any sample selection within selected segments can proceed, specially trained field
household listers will list all dwelling units and potential dwelling units within each selected area
segment. A dwelling unit is either a housing unit for a single household or one of the eligible
noninstitutional group quarters listing units that are part of the defined target population. The
listings will be based primarily on observations of the area segment and may include vacant
dwelling units and units that appear to be dwelling units but may actually be used for
nonresidential purposes. The objective of the listing is to attain as complete a listing of eligible
residential addresses as possible; any false positives for residences will be eliminated during the
household screening process after the sample is selected.
The sampling frame for the fourth stage of sample selection will be the lines of listed dwelling
units and potential dwelling units. After accounting for eligibility, nonresponse, and the fifthstage sample selection procedures, it was determined that roughly 233,248 lines will need to be
selected in order to obtain a sample of 69,007 responding persons distributed by state and agegroup as shown in Table 1.
Fifth Stage of Selection: Persons
After dwelling units are selected within each segment, an interviewer will visit each selected
dwelling unit to obtain a roster of all persons residing in the dwelling unit. This roster
information will be used to select 0, 1, or 2 persons for the survey. Sampling rates will be pre-set
by age group and State. Roster information will be entered directly into the electronic screening
instrument which will automatically implement this fifth stage of selection based on the State
and age group sampling parameters.
One exciting consequence of using an electronic screening instrument in the survey is the ability
to efficiently sample from all possible pairs of respondents within a dwelling unit while
preserving the target sampling rates for individuals within 5 age groups (12 to 17, 18 to 25, 26 to
34, 35 to 49, and 50 or older). Using an adaptation of Brewer’s method for samples of size 2, a
sample of 0, 1, or 2 persons will be selected from each dwelling unit. As a consequence, any two
survey-eligible people within a dwelling unit will have a known chance of being selected, that is,
all survey eligible pairs of people will have some nonzero chance of being selected. This feature
of the design is of interest to survey researchers because for example, it will allow analysts to
examine how the drug use propensity of one individual in a family will relate to the drug use
propensity of another family member residing in the same dwelling unit (e.g., the relationship of
drug use between a parent and child).

2

The sample will be expanded by 1,500 interviews in the first six months of the survey year. The additional
sample will be divided equally among the first two calendar quarters.

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As illustrated in Table 2, at the fifth stage of selection, roughly 100,746 people will be selected
from within 143,255 screened and eligible dwelling units. Assuming a 73% screening
completion rate and a 68% interview completion rate, these sample sizes are sufficient to obtain
the desired 69,007 person respondents.
Table 2. Summary of 2020 Main Study Design
Statistic

2020 NSDUH
750
6,000
233,248
196,240
143,255
100,746
69,007

State Sampling (SS) Regions
Segments
Selected Lines
Eligible Dwelling Units
Completed Screening Interviews
Selected Persons
Completed Interviews

2020 Rate

0.84
0.73
0.70
0.68

Expected Precision of Survey Estimates
The multistage, stratified 2020 survey design has been designed to achieve acceptable precision
for various person subpopulations of interest. The allocation of persons per state and age group
(12-17, 18-25, 26-34, 35-49, and 50 or older) was also taken as a requirement to support direct
estimation in some large sample states and SAE in the remaining states. Table 3 shows the
projected relative standard errors for selected prevalence measures.

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Table 3. Estimated Prevalences and Relative Standard Errors for Key Measures by
Demographic Domain
Measure

Past Month Alcohol Use
Past Month Alcohol Use
Past Month Alcohol Use
Past Month Alcohol Use
Past Month Alcohol Use
Past Month Alcohol Use
Past Month Binge Alcohol Use
Past Month Binge Alcohol Use
Past Month Marijuana Use
Past Month Marijuana Use
Past Month Marijuana Use
Past Month Marijuana Use
Past Month Marijuana Use
Past Month Marijuana Use
Past Month Marijuana Use
Past Month Cigarette Use
Past Month Cigarette Use
Past Month Pain Reliever Misuse
Past Month Pain Reliever Misuse
Past Year Alcohol Disorder
Past Year Illicit Drug Disorder
Past Year Substance Use Disorder
Past Year Specialty Substance Use
Treatment
Past Year SMI
Past Year MDE

Domain

12+
12-20
50+
API,12+
AIAN, 12+
Pregnant, 12-44
18-25
12+
12+
12-17
18-25
50+
API,12+
AIAN, 12+
Pregnant, 12-44
12-17
12+
18-25
12+
12+
12+
50+
12+
18+
18+

Prevalence

Projected
RSE

0.5167
0.1967
0.5066
0.3877
0.4063
0.1143
0.3688
0.2449
0.0955
0.0647
0.2213
0.0487
0.0405
0.1547
0.0705
0.0316
0.1789
0.0185
0.0119
0.0533
0.0277
0.0405

0.0071
0.0163
0.0124
0.0419
0.0755
0.2017
0.0136
0.0116
0.0180
0.0389
0.0193
0.0546
0.0996
0.1008
0.2359
0.0584
0.0153
0.0718
0.0513
0.0244
0.0311
0.0595

0.0093
0.0453
0.0707

0.0596
0.0288
0.0229

Note: Prevalence estimates are based on data from the 2017 NSDUH. Projected RSEs were
determined using 2014 through 2020 state and age sample allocations in a variance component
model. All model components were updated using 2017 NSDUH data.
Clinical Validation Study
To support the CVS, the 2020 NSDUH sample will be expanded by 1,500 interviews in the first
six months of the survey year. The additional sample will be allocated to state and age groups in
approximately the same proportions as in the CVS sample for the data collection quarters when
the CVS is implemented. The population total for the expanded sample will match the census
total after application of the appropriate weights.
During the NSDUH interview, a probability subsample will be selected from the full expanded
sample by means of a stratified random sample design. The stratified design will consist of eight
strata constructed from all combinations of past year cigarette, alcohol, and marijuana use. Some

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NSDUH respondents in each stratum will not be selected to allow for adjusting the weights of
the remaining NSDUH sample in the two quarters in which the subsampling for the CVS occurs.
To the extent possible (while assuring that not all individuals in a stratum are selected),
probability proportional to size sampling will be used to select respondents within strata. The
resulting CVS subsample will be approximately proportional by state and age.
NSDUH respondents selected for the CVS subsample will be administered new DSM-5
Substance Use Disorder modules. At the end of the NSDUH interview, these respondents will be
invited by the interviewer to participate in a follow-up clinical interview by telephone. Assuming
a 96 percent eligibility rate, an 86 percent agreement rate, and a 64 percent clinical interview
completion rate, the 1,500 main interview respondents are expected to yield approximately 800
completed clinical interviews.

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2020 NSDUH, Supporting Statement
Attachment L – Interview Incentive Receipt

Interview Incentive Receipt

U.S. Department of Health and Human Services
and
RTI International
thank you for participating in the 2020 National Survey on Drug Use and Health.
In appreciation of your participation in this important study, you are eligible to receive $30 in cash.
Since maintaining the confidentiality of your information is important to us, your name will not be entered on this
form. However, the interviewer must sign and date this form to certify you received (or declined) the cash incentive.

___________________________________
Interviewer

□

Accepted Cash Incentive

_________
Date

__ __ __ __ __ __ __ __ __ __ - __
Case ID

□

Declined Cash Incentive

If you ever feel that you need to talk to someone about mental health issues, you can call the National Lifeline
Network. Counselors are available to talk at any time of the day or night and they can give you information about
services in your area.
1-800-273-TALK or 1-800-273-8255
1-888-628-9454 (Spanish)
http://suicidepreventionlifeline.org/
If you ever feel that you need to talk to someone about drug use issues, you can call the Substance Abuse and Mental
Health Services Administration’s Treatment Referral Helpline. This is a 24-hour service that will help you locate
treatment options near you.
1-800-662-HELP or 1-800-662-4357
1-800-487-4889 (TDD)
http://findtreatment.samhsa.gov
Disposition: Top copy to Respondent, yellow to Field Supervisor, pink to Field Interviewer.

Recibo de incentivo por la entrevista

El Departamento de Salud y Servicios Humanos de los Estados Unidos
y
RTI International

le agradecen su participación en la Encuesta Nacional sobre la Salud y el Consumo de Drogas
del año 2020
Como muestra de nuestro agradecimiento por su participación en este importante estudio, usted tiene derecho a recibir
$30 dólares en efectivo.
Debido a que la privacidad de sus datos es importante para nosotros, su nombre no aparecerá en este documento. Sin
embargo, el entrevistador debe escribir la fecha en este recibo y firmarlo para certificar que usted recibió (o rechazó) el
incentivo en efectivo.

_______________________________
Entrevistador(a)

□ Aceptó el incentivo en efectivo

_________
Fecha

__ __ __ __ __ __ __ __ __ __ - __
No. de Idenficación del caso (ID)

□ Rechazó el incentivo en efectivo

Si alguna vez sintiera la necesidad de hablar con alguien acerca de asuntos relacionados con la salud mental, puede llamar a la
Red Nacional de la Línea de la Vida (National Lifeline Network). Consejeros están disponibles para hablarles a cualquier hora del
día o de la noche, y ellos le pueden dar información acerca de los servicios que se ofrecen en su zona.
1-888-628-9454 (español)
1-800-273-8255 o 1-800-273-TALK (inglés)
http://suicidepreventionlifeline.org
Si alguna vez sintiera la necesidad de hablar con alguien acerca de asuntos relacionados con las drogas, puede llamar a la Línea
de ayuda de referencias para servicios de tratamiento de la Administración de Servicios de Abuso de Sustancias y Salud Mental.
Este centro atiende las 24 horas del día y allí le darán información sobre los lugares cercanos a usted donde se ofrecen servicios de
tratamiento.
1-800-662-4357 o 1-800-662-HELP
1-800-487-4889 (línea TDD: para personas con problemas auditivos)
http://findtreatment.samhsa.gov
Distribución: hoja blanca: participante; copia amarilla: supervisor(a); copia rosada: entrevistador(a) .

2020 NSDUH, Supporting Statement
Attachment S – Certificate of Participation

U.S. Department of Health
and Human Services

Certificate of Participation
The U.S. Department of Health and Human Services and RTI International would like to thank

[Participant’s Signature]

for participating in the National Survey on Drug Use and Health
on
_____________________________
[Date of Interview]

Field Interviewer

Ilona S. Johnson,

FI ID #

National Field Director
RTI International
3040 Cornwallis Road
Research Triangle Park, NC 27709

This document certifies that the above named individual participated in NSDUH, a voluntary survey for the U.S. Department of Health and
Human Services. Across the country, some participants approach their school teachers or other group leaders to ask about possible special
community service credit as they completed this important national survey. The time commitment for participation in this survey is between 1
and 2 hours. A copy of the NSDUH brochure, which explains the study in more detail, should accompany this certificate. If you need further
information, contact the National Field Director, Ilona Johnson, at (800) 848-4079.