Table of Contents

Component Description

The vision section (abbreviated “VIQ” in the NHANES questionnaire variable naming convention scheme), provides personal interview data on several vision topics.

Topics and the target population groups in the VIQ section:

Eligible Sample

All survey participants 12 years and older were eligible for the first set of questions on blindness and general conditions of eyesight. Participants 20 years and older were asked further detailed questions about activity limitations due to their vision and cataract operation. Participants 40 years and older were eligible for a new set of questions on eye diseases, including glaucoma and age-related macular degeneration.

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.

Quality Assurance & Quality Control

Several types of quality control were implemented to ensure that high quality data were collected during the survey.

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.

Additional details describing the quality assurance/quality control processes are provided in the survey procedures manuals.

Data Processing and Editing

Frequency counts were checked, “skip” patterns were verified, and the reasonableness of responses to the questions was reviewed.

Analytic Notes

The 2005-2006 vision questionnaire data is similar to the 1999-2000, 2001-2002, and 2003-2004 publicly release files. However, target ages for 2005-2006 are different from data collected in previous years. Also, the blindness screening questions are different. For 2005-2006, persons who reported “Can’t see light” are then asked if they are “Blind in both eyes”. New questions about ophthalmologic disorders were first collected during 2005-2006 survey, and will not be found in the earlier data release files.

In addition to the vision questionnaire data, general vision examination and special ophthalmic examination data can be found in the vision section and ophthalmology section of the NHANES 2005-2006 Exam Files (VIX and OPX). These data may be linked using the unique survey participant identifier, SEQN.

Although these data were collected as part of the household questionnaire, if they are merged with the MEC exam data, exam sample weights should be used for the 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

SEQN - Respondent sequence number

Variable Name:
SEQN
SAS Label:
Respondent sequence number
English Text:
Respondent sequence number.
Target:
Both males and females 12 YEARS - 150 YEARS

VIQ010 - Can see light

Variable Name:
VIQ010
SAS Label:
Can see light
English Text:
Next I have general questions about (your/SP's) vision. With both eyes open, can (you/he/she) see light?
English Instructions:
CAPI INSTRUCTION: IF VIQ.010 = 2 AND MCQ.140 = 1, DISPLAY THE FOLLOWING MESSAGE: "YOU HAVE CODED THAT SP CANNOT SEE LIGHT - PLEASE VERIFY BY REENTERING THE RESPONSE." CAPI SHOULD DISPLAY VIQ.010 AGAIN WITH BLANK ENTRY. IF VIQ.010 = 2 AND MCQ.140 = 2, DISPLAY THE FOLLOWING MESSAGE: "YOU HAVE CODED THAT SP CANNOT SEE LIGHT. EARLIER SP REPORTED NO TROUBLE SEEING. RECONCILE RESPONSES WITH SP AND CHANGE RESPONSE TO ONE OF THE QUESTIONS BELOW." DISPLAY RESPONSES TO BOTH - WITH LABELS. MCQ.140 - TROUBLE SEEING, VIQ.010 - SEE LIGHT, HIGHLIGHT MUST BE ON VIQ.010.
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 7266 7266 VIQ031
2 No 1 7267
7 Refused 0 7267
9 Don't know 0 7267
. Missing 0 7267

VIQ017 - Blind in both eyes

Variable Name:
VIQ017
SAS Label:
Blind in both eyes
English Text:
{Are you/Is SP} blind in both eyes?
English Instructions:
CAPI INSTRUCTION: IF VIQ.010 = 2 (NO) AND VIQ.017 = 2 (NO), DISPLAY THE FOLLOWING MESSAGE: "YOU HAVE CODED THAT SP IS NOT BLIND. EARLIER SP REPORTED THAT HE/SHE CANNOT SEE LIGHT. RECONCILE RESPONSES WITH SP AND CHANGE RESPONSE TO ONE QUESTION BELOW:" DISPLAY RESPONSES TO BOTH VIQ.010 AND VIQ.017 WITH LABELS. PLACE HIGHLIGHT ON VIQ.010.
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 1 1 VIQ071
2 No 0 1
7 Refused 0 1
9 Don't know 0 1
. Missing 7266 7267

VIQ031 - General condition of eyesight

Variable Name:
VIQ031
SAS Label:
General condition of eyesight
English Text:
At the present time, would you say (your/SP'S) eyesight, with glasses or contact lenses if (you/he/she) wear them is.....
English Instructions:
CAPI INSTRUCTION: IF VIQ.010 = 2 AND VIQ.031 = 1 (EXCELLENT vision), DISPLAY THE FOLLOWING MESSAGE: "YOU HAVE CODED THAT SP CANNOT SEE LIGHT. SP REPORTED EXCELLENT VISION. RECONCILE RESPONSES WITH SP AND CHANGE RESPONSE TO ONE OF THE QUESTIONS BELOW." DISPLAY RESPONSES TO ALL - WITH LABELS. VIQ.010 - CAN'T SEE LIGHT VIQ.031 = 1 (EXCELLENT vision) HIGHLIGHT MUST BE ON VIQ.010.
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Excellent, 3082 3082
2 Good, 3027 6109
3 Fair, 912 7021
4 Poor, or 180 7201
5 Very poor? 57 7258
7 Refused 0 7258
9 Don't know 8 7266
. Missing 1 7267

VIQ041 - Time worrying about eyesight

Variable Name:
VIQ041
SAS Label:
Time worrying about eyesight
English Text:
How much of the time {do you/does SP} worry about {your/his/her} eyesight? Would you say . . .
Target:
Both males and females 12 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 None of the time, 4394 4394
1 A little of the time, 1358 5752
2 Some of the time, 960 6712
3 Most of the time, or 280 6992
4 All of the time? 267 7259
7 Refused 1 7260
9 Don't know 6 7266
. Missing 1 7267

VIQ051A - Difficulty reading ordinary newsprint

Variable Name:
VIQ051A
SAS Label:
Difficulty reading ordinary newsprint
English Text:
The next questions are about how much difficulty, if any, {you have/SP has} doing certain activities, such as reading ordinary newsprint or going down steps. If {you/s/he} usually wear{s} glasses or contact lenses to do these activities, please rate {you r/his/her} ability to do them while wearing {your/his/her} glasses or contacts. How much difficulty {do you/does SP} have . . .reading ordinary print in newspapers?
English Instructions:
HAND CARD VIQ1. READ CATEGORIES TO RESPONDENT IF NECESSARY.
Target:
Both males and females 20 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 No difficulty 3834 3834
2 A little difficulty 696 4530
3 Moderate difficulty 239 4769
4 Extreme difficulty 103 4872
5 Unable to do because of eyesight 53 4925
6 Does not do this for other reasons 53 4978
77 Refused 0 4978
99 Don't know 0 4978
. Missing 2289 7267

VIQ051B - Difficulty with up close work or chores

Variable Name:
VIQ051B
SAS Label:
Difficulty with up close work or chores
English Text:
How much difficulty {do you/does SP} have . . .doing work or hobbies that require {you/him/her} to see well up close such as cooking, sewing, fixing things around the house, or using hand tools?
Target:
Both males and females 20 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 No difficulty 4035 4035
2 A little difficulty 592 4627
3 Moderate difficulty 183 4810
4 Extreme difficulty 69 4879
5 Unable to do because of eyesight 35 4914
6 Does not do this for other reasons 63 4977
77 Refused 0 4977
99 Don't know 1 4978
. Missing 2289 7267

VIQ051C - Difficulty seeing steps/curbs-dim light

Variable Name:
VIQ051C
SAS Label:
Difficulty seeing steps/curbs-dim light
English Text:
How much difficulty {do you/does SP} have . . .going down steps, stairs, or curbs in dim light or at night?
Target:
Both males and females 20 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 No difficulty 4003 4003
2 A little difficulty 559 4562
3 Moderate difficulty 198 4760
4 Extreme difficulty 97 4857
5 Unable to do because of eyesight 26 4883
6 Does not do this for other reasons 92 4975
77 Refused 0 4975
99 Don't know 3 4978
. Missing 2289 7267

VIQ051D - Difficulty noticing objects to side

Variable Name:
VIQ051D
SAS Label:
Difficulty noticing objects to side
English Text:
How much difficulty {do you/does SP} have . . .noticing objects off to the side while {you are/s/he is} walking?
Target:
Both males and females 20 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 No difficulty 4427 4427
2 A little difficulty 338 4765
3 Moderate difficulty 120 4885
4 Extreme difficulty 51 4936
5 Unable to do because of eyesight 18 4954
6 Does not do this for other reasons 21 4975
77 Refused 0 4975
99 Don't know 3 4978
. Missing 2289 7267

VIQ051E - Difficulty findng object on crowdedshelf

Variable Name:
VIQ051E
SAS Label:
Difficulty findng object on crowdedshelf
English Text:
How much difficulty {do you/does SP} have . . .finding something on a crowded shelf?
Target:
Both males and females 20 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 No difficulty 4315 4315
2 A little difficulty 429 4744
3 Moderate difficulty 137 4881
4 Extreme difficulty 52 4933
5 Unable to do because of eyesight 15 4948
6 Does not do this for other reasons 26 4974
77 Refused 0 4974
99 Don't know 4 4978
. Missing 2289 7267

VIQ056 - Difficulty drivng daytime-familiar place

Variable Name:
VIQ056
SAS Label:
Difficulty drivng daytime-familiar place
English Text:
How much difficulty {do you/does SP} have driving during the daytime in familiar places?
English Instructions:
CAPI INSTRUCTION: IF VIQ.010 = 2 AND VIQ.056 = 1 (NO DIFFICULTY), DISPLAY THE FOLLOWING MESSAGE: "YOU HAVE REPORTED THAT SP CANNOT SEE LIGHT. SP REPORTED NO DIFFICULTY DRIVING. RECONCILE RESPONSES WITH SP AND CHANGE RESPONSE TO ONE OF THE QUESTIONS BELOW." DISPLAY RESPONSES TO ALL - WITH LABELS. VIQ.010 - CAN'T SEE LIGHT VIQ.056 = 1 (NO DIFFICULTY), HIGHLIGHT MUST BE ON VIQ.010.
Target:
Both males and females 20 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 No difficulty 4203 4203
2 A little difficulty 133 4336
3 Moderate difficulty 22 4358
4 Extreme difficulty 4 4362
5 Unable to do because of eyesight 52 4414
6 Does not do this for other reasons 278 4692
7 Never drove 286 4978
77 Refused 0 4978
99 Don't know 0 4978
. Missing 2289 7267

VIQ061 - Vision limits how long can do activities

Variable Name:
VIQ061
SAS Label:
Vision limits how long can do activities
English Text:
How limited {are you/is SP} in how long {you/s/he} can work or do other daily activities such as housework, child care, school, or community activities because of {your/his/her} vision? Would you say {you are/s/he is} limited . . .
Target:
Both males and females 20 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 None of the time, 4375 4375
1 A little of the time, 324 4699
2 Some of the time, 164 4863
3 Most of the time, or 61 4924
4 All of the time? 51 4975
7 Refused 0 4975
9 Don't know 3 4978
. Missing 2289 7267

VIQ071 - Ever had a cataract operation

Variable Name:
VIQ071
SAS Label:
Ever had a cataract operation
English Text:
{Have you/Has SP} ever had a cataract operation?
Target:
Both males and females 20 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 440 440
2 No 4534 4974 VIQ090
7 Refused 0 4974 VIQ090
9 Don't Know 5 4979 VIQ090
. Missing 2288 7267

VIQ081 - Operation in right, left or both eyes

Variable Name:
VIQ081
SAS Label:
Operation in right, left or both eyes
English Text:
Was the operation in {your/SPs} right eye, left eye, or both eyes?
Target:
Both males and females 20 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Right eye 75 75
2 Left eye 45 120
3 Both 313 433
7 Refused 0 433
9 Don't know 7 440
. Missing 6827 7267

VIQ090 - Ever told had glaucoma

Variable Name:
VIQ090
SAS Label:
Ever told had glaucoma
English Text:
{Have you/Has SP} ever been told by an eye doctor that {you have/s/he has} glaucoma (gla-co-ma), sometimes called high pressure in {your/his/her} eyes?
Target:
Both males and females 40 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 219 219
2 No 2813 3032 VIQ310
7 Refused 0 3032 VIQ310
9 Don't know 23 3055 VIQ310
. Missing 4212 7267

VIQ100 - Glaucoma in which eye

Variable Name:
VIQ100
SAS Label:
Glaucoma in which eye
English Text:
Was the glaucoma in {your/his/her} right eye, left eye, or both eyes?
Target:
Both males and females 40 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Right eye 41 41
2 Left eye 29 70
3 Both 133 203
7 Refused 0 203
9 Don't know 16 219
. Missing 7048 7267

VIQ310 - Told had macular degeneration

Variable Name:
VIQ310
SAS Label:
Told had macular degeneration
English Text:
{Have you/Has SP} ever been told by an eye doctor that {you have/s/he has} age-related macular (mac-u-lar) degeneration?
Target:
Both males and females 40 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Yes 141 141
2 No 2878 3019 End of Section
7 Refused 0 3019 End of Section
9 Don't know 36 3055 End of Section
. Missing 4212 7267

VIQ320 - Macular degeneration in which eye

Variable Name:
VIQ320
SAS Label:
Macular degeneration in which eye
English Text:
Was the age-related macular (mac-u-lar) degeneration in {your/his/her} right eye, left eye, or both eyes?
Target:
Both males and females 40 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
1 Right eye 20 20
2 Left eye 23 43
3 Both 86 129
7 Refused 0 129
9 Don't know 12 141
. Missing 7126 7267