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 Recent Tobacco Use (SMQRTU) data set provides details on use of cigarettes, pipes, cigars, and other forms of tobacco, including e-cigarette use, as well as nicotine replacement therapies in the past 5 days.
Eligible Sample
All participants aged 12 years and older in the NHANES 2017-March 2020 pre-pandemic sample were eligible. For participants aged 12-17, no proxy interviews were eligible.
Interview Setting and Mode of Administration
Questions were administered at the Mobile Examination Center (MEC) during the personal (MEC) Interview. Adults 18 years and older, were asked questions by trained interviewers using the Computer-Assisted Personal Interview (CAPI) system. For youths 12-17 years, questions were self-administered using the Audio Computer-Assisted Self-Interview (ACASI) system, in English and Spanish only.
Quality Assurance & Quality Control
The CAPI and ACASI systems are programmed with built-in consistency checks to reduce data entry errors. CAPI also uses online help screens to assist interviewers in defining key terms used in the questionnaire.
Data Processing and Editing
Edits were made to ensure completeness, consistency, and analytic usefulness of the data. A variable, SMAQUEX was created as a flag to designate each interview mode and age group.
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. 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 examination sample weights in the demographic data file should be used to calculate estimates for this combined data file. 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.
Additional questions on recent tobacco use including use of dissolvables, snus, and e-cigarettes were administered beginning in 2013-2014. At that time, separate questions about categories of tobacco categories “smoked,” “smokeless,” and “nicotine replacement products (adults 18+ years)” also were introduced. In recent cycles, details on use of some tobacco products were excluded, and question wording was edited. It is recommended that analysts review codebooks and documentation for question additions and deletions, changes to variable names, question wording, and skip patterns. Variable names from previous NHANES cycles were maintained when possible, and therefore may not match current question naming on questionnaire instruments. Prior to 2005-2006, the SMQRTU was named SMQMEC.
SMDANY: A summary variable for any tobacco use in the past 5 days. For adults 18+ years, this was based on responses to three questions on tobacco use (smoke, smokeless, nicotine replacement therapy products) (SMQ681, SMQ851, SMQ863). For youths 12-17 years, SMDANY was based on responses to SMQ681 and SMQ851 (smoke and smokeless).
SMQ690H: Use of e-cigarettes and other electronic devices was asked as a separate question during NHANES 2019-March 2020: “During the past 5 days, including today, did you use e-cigarettes? You may also know them as JUUL(TM), vape-pens, vapes, hookah-pens, e-hookahs, or vaporizers. These are battery-powered, usually contain liquid nicotine, and produce vapor instead of smoke?” In this data release, responses have been concatenated with the 2017-2018 question responses to prevent any possible disclosure of the data collection period.
SMQ690K: Users of other smokeless products were grouped due to limited numbers of counts for specific products. In 2019- March 2020, “dip” was included as an option.
Related questions on cigarette and tobacco use are located in the SMQ, SMQFAM and SMQSHS data files. Biomarkers for tobacco exposure including serum cotinine, are found in NHANES laboratory data files.
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.