• Component Description
• Eligible Sample
• Interview Setting and Mode of Administration
• Quality Assurance & Quality Control
• Data Processing and Editing
• Analytic Notes
• Codebook
  • SEQN - Respondent sequence number
  • SMQ020 - Smoked at least 100 cigarettes in life
  • SMD030 - Age started smoking cigarettes regularly
  • SMQ040 - Do you now smoke cigarettes
  • SMQ050Q - How long since quit smoking cigarettes
  • SMQ050U - Unit of measure (day/week/month/year)
  • SMD055 - Age last smoked cigarettes regularly
  • SMD057 - # cigarettes smoked per day when quit
  • SMQ077 - How soon after waking do you smoke
  • SMD641 - # days smoked cigs during past 30 days
  • SMD650 - Avg # cigarettes/day during past 30 days
  • SMD093 - May I please see the pack of cigarettes
  • SMDUPCA - Cig 12-digit Universal Product Code-UPC
  • SMD100BR - Cigarette Brand/sub-brand
  • SMD100FL - Filter type
  • SMD100MN - Menthol indicator
  • SMD100LN - Length
  • SMD100TR - FTC Tar Content
  • SMD100NI - FTC Nicotine Content
  • SMD100CO - FTC Carbon Monoxide Content
  • SMQ621 - Cigarettes smoked in entire life
  • SMD630 - Age first smoked whole cigarette
  • SMQ660 - Brands of cigarettes smoked/past mo
  • SMQ664M - Menthol or non-menthol Marlboro
  • SMQ664C - Menthol or non-menthol Camels
  • SMQ664W - Menthol or non-menthol Winston
  • SMQ664B - Menthol or non-menthol BensonHedges
  • SMQ664O - Menthol or non-menthol other brand
  • SMQ670 - Tried to quit smoking
  • SMAQUEX2 - Questionnaire Mode Flag
• Appendix: Variable names across cycles

National Health and Nutrition Examination Survey

2011-2012 Data Documentation, Codebook, and Frequencies

Smoking - Cigarette Use (SMQ_G)

Data File: SMQ_G.xpt

First Published: September 2013

Last Revised: May 2015

Component Description

The Smoking Cigarette use (variable name prefix SMQ) data set provides data on cigarette use; history of use, age at initiation, current use, past 30 day prevalence, amount, cigarette brand and other related details. It combines data from separate questionnaires asked of youth and adults.

Eligible Sample

All participants ages 12 years and older are eligible. For participants 12-19, there were no proxy interviews.

Interview Setting and Mode of Administration

For adults 20 and older, questions were asked, in the home, by trained interviewers using the Computer-Assisted Personal Interviewing (CAPI) system. For youths 12-19 years, the questions were asked at the Mobile Examination Center (MEC) during the MEC Interview using the Audio Computer-Assisted Self-Interviewing (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. Note that because data are self-reported, certain inconsistencies remain. For example, some adult respondents reported smoking “everyday” in SMQ040, but then reported smoking fewer than 30 days in question SMQ080. Analysts should review responses to questions carefully prior to analysis.

The cigarette brand was verified using the uniform product codes (UPC) found on the cigarette data pack shown to interviewers by the survey participant. As part of the data processing effort, UPCs were matched to an updated UPC cigarette database consisting of ACNielsen cigarette listings with detailed product descriptions for domestic and imported cigarettes sold in the United States. Domestic cigarettes were also linked with machine-measured tar, nicotine, and carbon monoxide content data obtained from the Federal Trade Commission. The database was prepared for the CDC’s Office on Smoking and Health by the Research Triangle Institute (RTI).

A special variable, SMAQUEX was created as a flag to designate each interview mode.

Analytic Notes

For youths, question SMQ621 which asks about the number of cigarettes smoked in lifetime replaced SMQ620 which asked if respondent had ever smoked a cigarette. Question SMQ621 includes a detailed and different response categories than SMQ620. Therefore, analysts will need to consider this change when merging several cycles. In addition, the descriptors “regular, lite, ultralite” for cigarette brands were not included in 2011-2012 due to required changes in manufacturer naming, labeling, and marketing of cigarettes brought about by the Family Smoking Prevention and Tobacco Control Act of 2009. Consult “variable names across cycles,” found at the end of this documentation for further clarification of these changes.

Additional questionnaires on tobacco use are located in SMQRTU and SMQFAM data files. Two biologic indicators of tobacco exposure serum cotinine (metabolite of nicotine) and urinary NNAL measurements are available in the COTNAL laboratory data file.

Note that for three data release cycles (1999-2004), all of the tobacco use data obtained for youths during the MEC ACASI interview was released in the SMQMEC data files, and tobacco use data for adults was released in both SMQ and SMQMEC data files. However, beginning in 2005-2006, the data release format was altered, combining data collection modes, and dividing the data by topic for all ages between two files: SMQ (cigarette use only) and SMQRTU (recent tobacco use). Therefore, when analysts are combining multiple years of tobacco data it is critical to refer all tobacco-related codebooks and carefully review the target age for each variable in the relevant data files.

The NHANES full sample 2-Year MEC Exam Weights (WTMEC2YR) should be used to analyze the 2011-2012 SMQ variables in conjunction with the laboratory measurements on tobacco exposure or other examination measurements.

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.

Codebook and Frequencies