• Component Description
• Eligible Sample
• Interview Setting and Mode of Administration
• Quality Assurance & Quality Control
• Data Processing and Editing
• Analytic Notes
• References
• Codebook
  • SEQN - Respondent sequence number
  • OCD150 - Type of work done last week
  • OCQ180 - Hours worked last week at all jobs
  • OCQ200 - CHECK ITEM
  • OCQ210 - Usually work 35 or more hours per week
  • OCD231 - Industry group code: current job
  • OCD241 - Occupation group code: current job
  • OCQ260 - Description of job/work situation
  • OCD270 - Number of months working in the main job
  • OCQ275 - Has anyone smoked where you work?
  • OCQ380 - Main reason did not work last week
  • OCD390G - Kind of work you have done the longest
  • OCD391 - Industry group code: longest job
  • OCD392 - Occupation group code: longest job
  • OCD395 - Duration of longest job (months)
  • OCQ500 - CHECK ITEM
  • OCQ510 - Ever had work exposure to mineral dusts?
  • OCQ520 - # of years exposed to mineral dusts
  • OCQ530 - Ever had work exposure to organic dusts?
  • OCQ540 - # of years exposed to organic dusts
  • OCQ550 - Ever exposed to exhaust fumes at work?
  • OCQ560 - # of years exposed to exhaust fumes
  • OCQ570 - Ever had work exposure to other fumes?
  • OCQ580 - # of years exposed to other fumes
• Appendix A
• Appendix B

National Health and Nutrition Examination Survey

2011-2012 Data Documentation, Codebook, and Frequencies

Occupation (OCQ_G)

Data File: OCQ_G.xpt

First Published: November 2013

Last Revised: September 2017

Note: Industry and occupation group code variables have been added for study participant's current and longest held jobs.

Component Description

The Occupation Questionnaire section (variable name prefix OCQ; questions OCD150 to OCQ580) contains survey participant interview data on employment and variables relating to the work environment.

OCQ section Topics:

• Data for Survey Participant’s Current Job (OCD231-OCD270): weekly hours worked, public vs. private sector, industry and occupation group, and duration of employment.
• Exposure to Workplace Tobacco Smoke at the Current Job (OCQ275).
• Data for the Survey Participant’s Longest Job (OCD390G-OCD395): industry and occupation group, duration of employment.
• Data for the Survey Participant’s Lifetime History of Exposure to Mineral and Organic Dusts, Gases, Fumes, and Vapors in the Workplace (OCQ510-OCQ580; administered to those ages 16-79 years).

Eligible Sample

All survey participants aged 16 years and older were eligible.

Interview Setting and Mode of Administration

These questions were asked, in the home, by trained interviewers using the Computer-Assisted Personal Interview (CAPI) system. Persons 16 years of age are interviewed directly.

Quality Assurance & Quality Control

The CAPI system is 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. During the 2011-2012 data collection cycle, periodic QC checks were performed on the Occupation questionnaire data being collected and interviewer specific feedback and retraining was performed as appropriate.

Data Processing and Editing

Questionnaire interview responses were entered into a pentop computer and then uploaded into a computerized database in the same manner as other sections of the Survey Participant Questionnaire. The data was then edited for completeness, consistency, and illogical values.

Analytic Notes

In general, analysts are advised to carefully review the question wording in the OCQ codebook also to make sure they understand question skip patterns and the definitions employed for Occupation-related variables. Some OCQ questions need to be considered as an integral part of data collection for other questionnaire sections, exam or laboratory Components.

Please note that military occupations are not permissible entries for NHANES current job data because for NHANES, only the civilian, non-institutionalized population is eligible to participate in the survey. However, civilian employees of the armed forces are included in the NHANES survey sample and military occupations are valid entries for the survey participant’s longest job data.

Current Job Information:
The primary focus of the OCQ Questionnaire is data collection for the participant’s work within the previous week (i.e., the participant’s Current Job). The participant’s Current Job is defined as the main paid job worked within the last week, including work on a family farm. When an individual currently worked multiple jobs, the participant was asked to designate one main job for the interview. Data collected included:

• The number of hours worked last week—all jobs;
• Whether the participant usually works 35 or more hours/week;
• Industry and Occupation group code data;
• Sector of employment (private, public);
• Number of months worked on the current, main job;
• The main reason the participant did not work last week (if not currently working); and
  A history of workplace tobacco smoke exposure.

Longest Job Information:
In NHANES 2011-12, both industry and occupation data and duration of employment were collected for the subject’s Longest Job. Industry information is also available in instances where the longest job is the same as the current job (OCD390G=2), or was the armed forces (OCD390G=3).

In NHANES 2011-12, additional questions were asked regarding a lifetime history of exposure to mineral and organic dusts, gases, fumes, and vapors (OCQ510-OCQ580). These questions were added to the survey as a part of an expanded respiratory health data collection for these survey years.

Related NHANES 2011-12 Data:
There are occupation-related items in the NHANES Physical Functioning (PFQ) questionnaire (PFQ049 and PFQ051) and two questions on veteran's status/military service in the Survey Participant Demographics (DEMO) data file (DMQMILIZ and DMQADFC). In NHANES 2011-12 Respiratory Health data was also collected: the dataset SPX contains Spirometry exam data; ENX contains data on exhaled nitric oxide measurements; MCQ contains questionnaire data on a prior medical diagnosis of asthma and chronic obstructive pulmonary disease; and RDQ contains questionnaire data on recent respiratory symptoms. The NHANES smoking questionnaire (SMQ) and laboratory data for serum cotinine are logically related to the workplace smoke exposure data collection.

Industry & Occupation Coding:
Four digit codes were applied to the NHANES 2011-2012 occupation and industry data using the 2002 U.S. Bureau of the Census Industrial & Occupational Classification coding system. The coding was done by the Division of Surveillance, Hazard Evaluations, and Field Studies (DSHEFS), which is part of CDC’s National Institute for Occupational Safety and Health (NIOSH). The 2002 Census Bureau industry codes are based on the year 2002 North American Industry Classification System, and the 2002 Census Bureau occupation codes are based on the year 2000 Standard Occupational Classification System. In the OCQ_G public release data file, group code variables are provided that classify an NHANES survey participant to one of 22 industry groups and to one of 23 occupation groups. Access to the more detailed four-digit occupation and industry variables is available through the NHANES Research Data Center (RDC).

Over the past six cycles, the coding system used to code NHANES data have changed. Researchers need to review these coding systems to ensure that they are coding and interpreting their findings correctly.

• The U.S. Census Bureau’s 2002 version of its Occupation and Industry coding system was used for detailed coding of the 2007-2008, 2009-2010, and 2011-2012 occupation and industry group data.
• The U.S. Census Bureau’s 2000 version of its Occupation and Industry coding system was used for detailed coding of the 2001-2002, 2003-2004, and 2005-2006 occupation and industry group data.

The 2000 and 2002 versions of the Census Bureau Industry and Occupation codes are comparable in many, but not in all respects, and data analysts who wish to combine NHANES cycles together should consult NIOSH’s documentation on the comparability of these 2 versions of the Census Bureau’s coding system and available crosswalks before performing their analyses.

Coding manuals, detailed data dictionaries of the alphabetical and classified indices of industries and occupations, and information about crosswalks between the coding systems are available (NIOSH, 2017).

Appendix A provides SAS™ program format statements useful for formatting the NHANES 2011-12 occupation and industry group code data. Appendix B provides tables showing the detailed U.S. Census occupation and industry source codes used in creating the NHANES 2011-12 occupation and industry group codes.

Detailed occupation and industry codes for the 1999-2000, 2001-2002, and 2003-2004 cycles are not available through the RDC, and at this time, there is no timeline to release them.

The OCQ data were collected as part of the household questionnaire and, therefore, the full sample NHANES interview weights WTINT2YR should be used for statistical analysis. However, if the OCQ data are merged with the MEC exam or laboratory data, then the NHANES examination sample weights WTMEC2YR should be used for analyses. 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.

References

• National Institute for Occupational Safety and Health (NIOSH). 2017. https://www.cdc.gov/niosh/topics/coding/nioccsuserdocumentation.html

Codebook and Frequencies