• 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
  • DIQ219 - CHECK ITEM
  • DIQ220 - When was your diabetes diagnosed
  • DIQ159 - CHECK ITEM
  • DIQ160 - Ever told you have prediabetes
  • DIQ170 - Ever told have health risk for diabetes
  • DIQ180 - Had blood tested past three years
  • DIQ190A - Past yr told control weight
  • DIQ190B - Past yr told increase physical activity
  • DIQ190C - Past yr told reduce fat/calories in diet
  • DIQ200A - Are you controlling weight
  • DIQ200B - Are you increasing physical activity
  • DIQ200C - Are you reducing fat/calories in diet
  • DIQ050 - Taking insulin now
  • DID060 - How long taking insulin
  • DIQ060U - Unit of measure (month/year)
  • DID065 - CHECK ITEM
  • DID070 - Take diabetic pills to lower blood sugar
  • DID229 - CHECK ITEM
  • DIQ230 - How long ago saw a diabetes specialist
  • DIQ240 - Is there one Dr you see for diabetes
  • DID250 - Past year how many times seen doctor
  • DID260 - How often check blood for glucose/sugar
  • DIQ260U - Unit of measure (day/week/month/year)
  • DID270 - Past year times checked for A1C
  • DIQ280 - What was your last A1C level
  • DIQ290 - What does Dr say A1C should be
  • DIQ295 - CHECK ITEM
  • DIQ300S - What was your recent SBP
  • DIQ300D - What was your recent DBP
  • DID310S - What does Dr say SBP should be
  • DID310D - What does Dr say DBP should be
  • DID320 - What was most recent LDL number
  • DID330 - What does Dr say LDL should be
  • DID340 - Past year times Dr check feet for sores
  • DID350 - How often do you check your feet
  • DIQ350U - Unit of measure (day/week/month/year)
  • DIQ360 - Last time had pupils dilated for exam
  • DIQ080 - Diabetes affected eyes/had retinopathy

National Health and Nutrition Examination Survey

2007-2008 Data Documentation, Codebook, and Frequencies

Diabetes (DIQ_E)

Data File: DIQ_E.xpt

First Published: September 2009

Last Revised: April 2011

Component Description

The diabetes section (prefix DIQ) provides personal interview data on diabetes, prediabetes, use of insulin or oral hypoglycemic medications, and diabetic retinopathy. It also provides self-reported information on awareness of risk factors for diabetes, healthy lifestyle changes to lower the risk of certain diseases, general knowledge of diabetic complications, and medical or personal care associated with these conditions.

Eligible Sample

All survey participants aged 1 year and older were eligible. The questions asked varied by age and history of diabetes. Please refer to check items in 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 before the physical examination, in the home, using the Computer-Assisted Personal Interviewing-CAPI (interviewer administered) system. Hand cards showing response categories were also used for some questions. When necessary, household interviewers read the hand cards to respondents. Persons 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 individuals who could not answer the questions themselves.

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.

Data Processing and Editing

Frequency counts were checked, “skip” patterns were verified, and the reasonableness of question responses was reviewed. Edits were made to some variables 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.

DID250: How many times have you seen doctor in the past 12 months?

If the time was reported as “None”, the value was coded as 0.

DID260: How often do you check your blood for glucose or sugar?

This variable was coded as 0 and 666 for participants who reported “Never” and “Unable to do activity (blind)” respectively.

DID270: During the past 12 months, how many times has a doctor checked you for glycosylated hemoglobin or “A1C”?

This variable was coded as 0 and 666 for participants who reported “Not tested in the last 12 months” and “Never heard of A1C test” respectively.

DID320: What was your most recent LDL cholesterol number?

This variable was coded as 5555 and 6666 for participants who reported “Never heard of LDL” and “Never had cholesterol test” respectively.

DID310S/D: What does doctor say your blood pressure should be?

DID330: What does doctor say your LDL cholesterol should be?

If a participant reported “Provider did not specify goal”, the value of corresponding variable was coded as 6666.

DID340: During the past 12 months, how many times has a doctor checked your feet for any sores or irritations?

DID350: How often do you check your feet for sores or irritation?

If the time was reported as “None”, the value of corresponding variable was coded as 0.

Analytic Notes

In the 2007–2008 data, the core questions for the diabetes component, including doctor diagnosed diabetes, duration of diabetes, insulin use, oral diabetic medication, and diabetic retinopathy are similar to the 2005–2006 and 1999–2004 publicly release data. The remaining questions, including awareness of risk factors for diabetes, healthy lifestyle changes to lower risk of certain disease, general knowledge of diabetic complications, and medical or personal care associated with diabetes are similar to the 2005–2006 publicly release data. The responses to these questions reflect the respondent’s knowledge and may not be biologically reasonable.

When combining DIQ data from different survey cycles, please note that there is a possible name change for the same question across release cycles due to the ways of data process and editing. The following cross reference table shows these variable names through the 2007-2008.

Variable names across cycles

Label	1999–2000	2001–2002	2003–2004	2005–2006	2007–2008
Age when first told you had diabetes	DIQ040G	DID040G	DID040G	DID040	DID040
Number of years of age	DIQ040Q	DID040Q	DID040Q
How long taking insulin	DIQ060G	DID060G	DID060G	DID060	DID060
Number of mos/yrs taking insulin	DIQ060Q	DID060Q	DID060Q
Take diabetic pills to lower blood sugar	DIQ070	DIQ070	DIQ070	DID070	DID070

The analysis of NHANES 2007–2008 diabetes questionnaire 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 itself. However if DIQ data are merged with the MEC examination data or laboratory data, the MEC examination weights should be used for analyses. If DIQ data are merged with laboratory sub-sample data, sub-sample weights should be used for analyses.

Please refer to the Analytic Guidelines for further details on the use of sample weights and other analytic issues. The Analytic Guidelines are available on the NHANES website.

Codebook and Frequencies