• 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
  • DIQ010 - Doctor told you have diabetes
  • DID040 - Age when first told you had diabetes
  • DIQ159 - CHECK ITEM
  • DIQ160 - Ever told you have prediabetes
  • DIQ180 - Had blood tested past three years
  • DIQ050 - Taking insulin now
  • DID060 - How long taking insulin
  • DIQ060U - Unit of measure (month/year)
  • DIQ065 - CHECK ITEM
  • DIQ070 - Take diabetic pills to lower blood sugar

National Health and Nutrition Examination Survey

August 2021-August 2023 Data Documentation, Codebook, and Frequencies

Diabetes (DIQ_L)

Data File: DIQ_L.xpt

First Published: September 2024

Last Revised: NA

Component Description

The diabetes questionnaire (DIQ_L) data file provides personal interview data on diabetes, prediabetes, and use of insulin and/or oral hypoglycemic medications.

Eligible Sample

All survey participants aged 1 year and older in the NHANES August 2021─August 2023 sample are included in this dataset. The questions asked varied by age and history of diabetes. Please refer to the diabetes questionnaire and corresponding codebook for question-specific details about the eligible target group.

Interview Setting and Mode of Administration

These questions were asked in the home or on the phone, by trained interviewers using the Computer-Assisted Personal Interview (CAPI) system. Help screens were provided for some medical terms in the questionnaires. When necessary, household interviewers read the help screen to survey participants.

Participants 16 years of age and older and emancipated minors were interviewed directly. A proxy provided information for survey participants who were under 16 years of age and for participants who could not answer the questions themselves.

The NHANES August 2021-August 2023 questionnaires are available on the NHANES website.

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. Interviewers were required to audio-record interviews. The recorded interviews were reviewed by interviewer supervisors and NCHS staff.

Data Processing and Editing

Frequency counts were checked, “skip” patterns were verified, and the reasonableness of question responses was reviewed. Edits were made to ensure the completeness, consistency, and analytic usefulness of the data. Edits were also made, when necessary, to address data disclosure concerns.

DID040: How old when a doctor first told you that you had diabetes?
All responses of age 80 years and older are coded as “80”, to be consistent with the coding for the participant age variable in the demographics file. Also, the onset of diabetes at age less than 1 year was coded as 666.

DID060: For how long have you been taking insulin? 
Taking insulin less than 1 month was coded as 666.

Analytic Notes

The core questions including doctor diagnosed diabetes, duration of diabetes, prediabetes, and oral diabetes medication are the same as the previous public use data. The insulin use question (variables DIQ050, DID060, DIQ060U) was only asked for participants with diagnosed diabetes in the DIQ_L data. The questions about the participants’ knowledge of their own levels of A1C, blood pressure, and cholesterol and knowledge of appropriate target levels, as suggested by their physicians were not collected in this survey cycle.

The analysis of NHANES August 2021–August 2023 DIQ data must be conducted using the appropriate survey design variables, sample weights, and the basic demographic variables. Interview weights should only be used if questionnaire data are analyzed by themselves. However, if DIQ data are merged with the MEC examination data or laboratory full sample data, the MEC examination weights should be used for analyses. If DIQ data are merged with the laboratory fasting glucose data, fasting subsample weights should be used for analyses.

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

Codebook and Frequencies