Table of Contents

Component Description

The NHANES program suspended field operations in March 2020 due to the coronavirus disease 2019 (COVID-19) pandemic. As a result, data collection for the NHANES 2019-2020 cycle was not completed and the collected data are not nationally representative. Therefore, data collected from 2019 to March 2020 were combined with data from the NHANES 2017-2018 cycle to form a nationally representative sample of NHANES 2017-March 2020 pre-pandemic data. These data are available to the public. Please refer to the Analytic Notes section for more details on the use of the data.

The Drug Use questionnaire (variable name prefix DUQ) focuses on lifetime and current use of marijuana or hashish, cocaine, heroin, and methamphetamine, as well as intravenous use of these and other drugs.

Eligible Sample

Participants aged 12 to 59 years, in the NHANES 2017-March 2020 pre-pandemic sample, were eligible; however, only data from participants aged 18-59 are included in this file available through the NCHS Research Data Center (RDC). Data collected for participants aged 12-17 years are available in a separate file through the RDC. Mentally impaired participants, or participants who were unable to understand English, Spanish, Korean, Vietnamese, or Chinese (traditional/Mandarin, simplified/Mandarin, and traditional/Cantonese) were excluded from the DUQ.

Interview Setting and Mode of Administration

The DUQ was administered at the Mobile Examination Center (MEC) during the MEC Interview. For participants aged 12 to 59, questions were self-administered using the Audio Computer-Assisted Self-Interview (ACASI) system.

The ACASI was conducted in one of the following languages: English, Spanish, Korean, Vietnamese, or Chinese (traditional/Mandarin, simplified/Mandarin, and traditional/Cantonese).

The ACASI enables participants both to hear questions through headphones and read questions on the computer screen. Participants moved at their own speed and touched the screen to indicate their responses. No proxy respondents or translators were used during the ACASI.

The NHANES 2017-2018 and 2019-2020 questionnaires are available on the NHANES website.

Quality Assurance & Quality Control

For details on the QA/QC process for this component, please refer to the MEC Interviewer Procedures manual on the NHANES website.

Data Processing and Editing

The data were edited for completeness, consistency, and illogical values.

To decrease the risk of disclosure, additional “bottom” summary codes were implemented for the variable DUQ210. For the age of first use of marijuana, participants who reported an age less than or equal to 11 years were coded as “11 years or younger.” In addition, the variable DUD380F includes participants who reported injecting steroids or “any other drug” (i.e., other than cocaine, heroin, or methamphetamine, which are asked about separately) using a needle. In prior cycles, these frequencies were available separately in variables DUQ380D and DUQ380E, respectively.

To make the data collected in the NHANES 2017-2018 cycle compatible with those collected in the NHANES 2019-March 2020, changes were made to both datasets.

For 2017-2018, the variables DUQ220Q and DUQ220U were used to backfill DUQ230 for ever users of marijuana. Respondents who reported use of marijuana more than 30 days, 4 weeks, 1 month or 1 year ago were recoded to 0 for DUQ230. Those who reported “Refused” or “Don’t Know” to DUQ220Q/DUQ220U were recoded to 777 or 999, respectively, for DUQ230.

For data collected in 2019-March 2020, DUQ005 was renamed to DUQ210 and used to create DUQ200. Respondents who reported an age of first use of marijuana for DUQ005/DUQ210 were coded as 1 for DUQ200, those who reported never use were coded as 2, and “Refused” and “Don’t Know” were coded as 7 and 9, respectively. After creating the variable DUQ200, DUQ210 was set to missing for respondents who didn’t report an age of first use of marijuana. The variables DUQ250, DUQ290 and DUQ330 were used to create DUQ240. Respondents who reported “Yes” to DUQ250, DUQ290 or DUQ330 were coded as 1 for DUQ240, those who reported “No” to DUQ250, DUQ290 and DUQ330 were coded as 2, those who reported “Refused” to DUQ250, DUQ290 or DUQ330 were coded as 7, and those who reported “Don’t Know” to DUQ250, DUQ290 or DUQ330 were coded as 9. After creating DUQ240, the variables DUQ250, DUQ290, and DUQ330 were set missing for respondents not coded as “Yes” for ever use of cocaine, crack cocaine, heroin, or methamphetamine.

Analytic Notes

The COVID-19 pandemic required suspension of NHANES 2019-2020 field operations in March 2020 after data were collected in 18 of the 30 survey locations in the 2019-2020 sample. Data collection was cancelled for the remaining 12 locations. Because the collected data from 18 locations were not nationally representative, these data were combined with data from the previous cycle (2017-2018) to create a 2017-March 2020 pre-pandemic data file. A special weighting process was applied to the 2017-March 2020 pre-pandemic data file. The resulting sample weights in the demographic data file should be used to calculate estimates from the combined cycles. These sample weights are not appropriate for independent analyses of the 2019-2020 data and will not yield nationally representative results for either the 2017-2018 data alone or the 2019-March 2020 data alone. Please refer to the NHANES website for additional information for the NHANES 2017-March 2020 pre-pandemic data, and for the previous 2017-2018 public use data file with specific weights for that 2-year cycle.

Please refer to the NHANES Analytic Guidelines and the on-line NHANES Tutorial for further details on the use of sample weights and other analytic issues.

Since the questionnaire was asked in the MEC, the MEC sample weights should be used in the analysis.

Codebook and Frequencies

SEQN - Respondent sequence number

Variable Name:
SEQN
SAS Label:
Respondent sequence number
English Text:
Respondent sequence number.
Target:
Both males and females 18 YEARS - 59 YEARS

DUQ200 - Ever used marijuana or hashish

Variable Name:
DUQ200
SAS Label:
Ever used marijuana or hashish
English Text:
The following questions ask about use of drugs not prescribed by a doctor. Please remember that your answers to these questions are strictly confidential. The first questions are about marijuana and hashish. Marijuana is also called pot or grass. Marijuana is usually smoked, either in cigarettes, called joints, or in a pipe. It is sometimes cooked in food. Hashish is a form of marijuana that is also called 'hash.' It is usually smoked in a pipe. Another form of hashish is hash oil. Have you ever, even once, used marijuana or hashish?
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 3004 3004
2 No 2335 5339 DUQ240
7 Refused 4 5343 DUQ240
9 Don't know 5 5348 DUQ240
. Missing 476 5824

DUQ210 - Age when first tried marijuana

Variable Name:
DUQ210
SAS Label:
Age when first tried marijuana
English Text:
How old were you the first time you used marijuana or hashish?
English Instructions:
ENTER AGE IN YEARS
Target:
Both males and females 18 YEARS - 59 YEARS
Hard Edits:
0 to 59
Code or Value Value Description Count Cumulative Skip to Item
12 to 55 Range of Values 2902 2902
11 11 years or under 101 3003
777 Refused 0 3003
999 Don't know 1 3004
. Missing 2820 5824

DUD230 - # days used marijuana or hashish/month

Variable Name:
DUD230
SAS Label:
# days used marijuana or hashish/month
English Text:
During the past 30 days, on how many days did you use marijuana or hashish?
English Instructions:
HARD EDIT VALUES: 1-30. Error message: "Your response cannot exceed 30 days. Please press the "Back" button, press "Clear," and try again." ENTER A NUMBER.
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 to 30 Range of Values 2997 2997
777 Refused 2 2999
999 Don't know 4 3003
. Missing 2821 5824

DUQ240 - Ever used cocaine/heroin/methamphetamine

Variable Name:
DUQ240
SAS Label:
Ever used cocaine/heroin/methamphetamine
English Text:
Have you ever used cocaine, crack cocaine, heroin, or methamphetamine?
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 975 975
2 No 4366 5341 DUQ370
7 Refused 3 5344 DUQ370
9 Don't know 3 5347 DUQ370
. Missing 477 5824

DUQ250 - Ever use any form of cocaine

Variable Name:
DUQ250
SAS Label:
Ever use any form of cocaine
English Text:
The following questions are about cocaine, including all the different forms of cocaine such as powder, 'crack', 'free base', and coca paste. Have you ever, even once, used cocaine, in any form?
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 935 935
2 No 39 974 DUQ290
7 Refused 1 975 DUQ290
9 Don't know 0 975 DUQ290
. Missing 4849 5824

DUQ270Q - Last time you used cocaine, in any form

Variable Name:
DUQ270Q
SAS Label:
Last time you used cocaine, in any form
English Text:
How long has it been since you last used cocaine, in any form?
English Instructions:
ENTER NUMBER OF DAYS, WEEKS, MONTHS, OR YEARS
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 to 120 Range of Values 933 933
7777 Refused 1 934
9999 Don't know 0 934
. Missing 4890 5824

DUQ270U - Last time you used cocaine/unit

Variable Name:
DUQ270U
SAS Label:
Last time you used cocaine/unit
English Text:
How long has it been since you last used cocaine, in any form?
English Instructions:
ENTER UNIT
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Days 70 70
2 Weeks 39 109
3 Months 99 208
4 Years 725 933
7 Refused 0 933
9 Don't know 0 933
. Missing 4891 5824

DUQ290 - Ever used heroin

Variable Name:
DUQ290
SAS Label:
Ever used heroin
English Text:
The following questions are about heroin. Have you ever, even once, used heroin?
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 144 144
2 No 831 975 DUQ330
7 Refused 0 975 DUQ330
9 Don't know 0 975 DUQ330
. Missing 4849 5824

DUQ310Q - Last time used heroin

Variable Name:
DUQ310Q
SAS Label:
Last time used heroin
English Text:
How long has it been since you last used heroin?
English Instructions:
ENTER NUMBER OF DAYS, WEEKS, MONTHS, OR YEARS
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 to 999 Range of Values 144 144
7777 Refused 0 144
9999 Don't know 0 144
. Missing 5680 5824

DUQ310U - Last time used heroin/unit

Variable Name:
DUQ310U
SAS Label:
Last time used heroin/unit
English Text:
How long has it been since you last used heroin?
English Instructions:
ENTER UNIT
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Days 17 17
2 Weeks 3 20
3 Months 19 39
4 Years 105 144
7 Refused 0 144
9 Don't know 0 144
. Missing 5680 5824

DUQ330 - Ever used methamphetamine

Variable Name:
DUQ330
SAS Label:
Ever used methamphetamine
English Text:
The following questions are about methamphetamine, also known as crank, crystal, ice or speed. Have you ever, even once, used methamphetamine?
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 360 360
2 No 614 974 DUQ370
7 Refused 0 974 DUQ370
9 Don't know 1 975 DUQ370
. Missing 4849 5824

DUQ350Q - Last time used methamphetamine

Variable Name:
DUQ350Q
SAS Label:
Last time used methamphetamine
English Text:
How long has it been since you last used methamphetamine?
English Instructions:
ENTER NUMBER OF DAYS, WEEKS, MONTHS, OR YEARS
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 to 40 Range of Values 359 359
7777 Refused 0 359
9999 Don't know 0 359
. Missing 5465 5824

DUQ350U - Last time used methamphetamine/unit

Variable Name:
DUQ350U
SAS Label:
Last time used methamphetamine/unit
English Text:
How long has it been since you last used methamphetamine?
English Instructions:
ENTER UNIT
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Days 39 39
2 Weeks 12 51
3 Months 30 81
4 Years 278 359
7 Refused 0 359
9 Don't know 0 359
. Missing 5465 5824

DUQ370 - Ever use a needle to inject illegal drug

Variable Name:
DUQ370
SAS Label:
Ever use a needle to inject illegal drug
English Text:
The following questions are about the different ways that certain drugs can be used. Have you ever, even once, used a needle to inject a drug not prescribed by a doctor?
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 115 115
2 No 5231 5346 End of Section
7 Refused 0 5346 End of Section
9 Don't know 0 5346 End of Section
. Missing 478 5824

DUQ380A - Drugs injected - Cocaine

Variable Name:
DUQ380A
SAS Label:
Drugs injected - Cocaine
English Text:
Which of the following drugs have you injected using a needle?
English Instructions:
SHOW ALL FIVE ITEMS ON SINGLE ACASI SCREEN HARD EDIT: AT LEAST ONE ITEM IN DUQ380 MUST BE SELECTED. Error message: "Earlier you reported using a needle to inject drugs not prescribed by a doctor. Which of these drugs did you inject?"
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Cocaine 59 59
7 Refused 0 59
9 Don't know 0 59
. Missing 5765 5824

DUQ380B - Drugs injected - Heroin

Variable Name:
DUQ380B
SAS Label:
Drugs injected - Heroin
English Text:
Which of the following drugs have you injected using a needle?
English Instructions:
SHOW ALL FIVE ITEMS ON SINGLE ACASI SCREEN HARD EDIT: AT LEAST ONE ITEM IN DUQ380 MUST BE SELECTED. Error message: "Earlier you reported using a needle to inject drugs not prescribed by a doctor. Which of these drugs did you inject?"
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
2 Heroin 65 65
. Missing 5759 5824

DUQ380C - Drugs injected - Methamphetamine

Variable Name:
DUQ380C
SAS Label:
Drugs injected - Methamphetamine
English Text:
Which of the following drugs have you injected using a needle?
English Instructions:
SHOW ALL FIVE ITEMS ON SINGLE ACASI SCREEN HARD EDIT: AT LEAST ONE ITEM IN DUQ380 MUST BE SELECTED. Error message: "Earlier you reported using a needle to inject drugs not prescribed by a doctor. Which of these drugs did you inject?"
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
3 Methamphetamine 40 40
. Missing 5784 5824

DUD380F - Drugs injected - Steroids or other drugs

Variable Name:
DUD380F
SAS Label:
Drugs injected - Steroids or other drugs
English Text:
Which of the following drugs have you injected using a needle?
English Instructions:
SHOW ALL FIVE ITEMS ON SINGLE ACASI SCREEN HARD EDIT: AT LEAST ONE ITEM IN DUQ380 MUST BE SELECTED. Error message: "Earlier you reported using a needle to inject drugs not prescribed by a doctor. Which of these drugs did you inject?"
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
6 Steroids or any other drugs 23 23
. Missing 5801 5824

DUQ400Q - Last time injected drugs

Variable Name:
DUQ400Q
SAS Label:
Last time injected drugs
English Text:
How long ago has it been since you last used a needle to inject a drug not prescribed by a doctor?
English Instructions:
ENTER NUMBER OF DAYS, WEEKS, MONTHS, OR YEARS
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 to 999 Range of Values 114 114
7777 Refused 1 115
9999 Don't know 0 115
. Missing 5709 5824

DUQ400U - Last time injected drugs/unit

Variable Name:
DUQ400U
SAS Label:
Last time injected drugs/unit
English Text:
How long ago has it been since you last used a needle to inject a drug not prescribed by a doctor?
English Instructions:
ENTER UNIT
Target:
Both males and females 18 YEARS - 59 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Days 9 9
2 Weeks 1 10
3 Months 14 24
4 Years 90 114
7 Refused 0 114
9 Don't know 0 114
. Missing 5710 5824