Survey Analysis Plan

Vision & Eye Health Surveillance System

LAST UPDATED:

MAY 1, 2018

PRESENTED TO:

Jinan Saaddine,

Division of Diabetes

Translation,

Centers for Disease

Control and Prevention

PRESENTED BY:

John Wittenborn,

Clare Davidson,

David Rein,

NORC at the University of Chicago

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

Table of Contents

Introduction ................................................................................................................................. 1

The Vision and Eye Health Surveillance System (VEHSS) .................................................. 1

Overview of the Integration of National Surveys in VEHSS .................................................. 1

Draft Analysis Plan Outline ........................................................................................................ 3

Step 1: Survey Validation and Dataset Preparation ............................................................. 3

Step 2: Define Outcome and Stratification Variables ............................................................ 3

Step 3: Estimate Results ...................................................................................................... 5

Step 4: Dataset preparation .................................................................................................. 6

Disseminating Results and Statistics ....................................................................................... 8

Data Reports ......................................................................................................................... 8

Appendix A. Categorization Schema for National Survey Variables ................................... 10

Survey Questions for Analysis ............................................................................................ 12

Appendix B. VEHSS Uniform Data Table Template ............................................................... 17

Appendix C. VEHSS Uniform Data Template: Survey Stratification Factors Data

Dictionary .................................................................................................................................. 19

Appendix D. Default Prevalence Estimates Stratifications for Survey Data ....................... 22

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

List of Tables

Table 1. Example Data Dictionary Table .................................................................... 8

Table 2. Example Summary Outcome Table ............................................................. 9

Table 3. Overview of Surveys and TOPICS ............................................................. 11

Table 4. Survey questions included in analysis ........................................................ 12

Table 5. VEHSS Uniform Data Table Template ....................................................... 17

Table 6. PUF Ages ................................................................................................... 19

Table 7. Race/Ethnicity Categories .......................................................................... 19

Table 8. Gender Categories ..................................................................................... 19

Table 9. Risk Factors ............................................................................................... 20

Table 10. Locations .................................................................................................... 20

Table 11. Insurance (RDF only) ................................................................................. 21

DISCLAIMER: The findings and conclusions in this report are those of the authors and do not necessarily

represent the official position of NORC at the University of Chicago or the Centers for Disease Control

and Prevention.

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

Introduction

The Vision and Eye Health Surveillance System (VEHSS)

The Centers for Disease Control and Prevention (CDC) issued a cooperative agreement with NORC at the

University of Chicago (NORC) to establish a national Vision and Eye Health Surveillance System

(VEHSS). NORC has partnered with leading organizations in vision care and research, and an expert

panel provides oversight and review of VEHSS results and work products.

This document serves as a data analysis guide for survey data used by VEHSS analysts and data providers

and may be updated throughout the course of the project.

Overview of the Integration of National Surveys in VEHSS

National surveys play an important role in VEHSS. The five-step process described below provides an

overview of VEHSS’ approach to compile and leverage vision and eye health data across multiple

national surveys. The goal is to present those data to the public and use them to estimate national

prevalence and service utilization rates.

■ Project Step 1. Identify sources of vision and eye health related survey data

In the project’s first step, we identified and reviewed different potential data sources,

including national surveys. We identified 16 national surveys with vision and eye health

related instruments.

■ Project Step 2. Summarize characteristics of the survey methodology and instruments

In the next step, we compiled the key methodological features and eye and vision related

questions and measures in each survey. These were summarized and reported in VEHSS’

“Review of National Survey Data on Eye Health Report.”

■ Project Step 3. Identify and define categories to organize and present outcomes from

multiple surveys in a comparable manner

We created a 2-level categorization schema (categories and subgroups) for all survey

questions from the 16 identified surveys. Based on survey methodology, sampling frame and

included instruments, we recommended including the following six surveys:

1. American Community Survey (ACS)

2. Behavioral Risk Factors Surveillance System (BRFSS)

3. Medicare Current Beneficiary Survey (MCBS)

4. National Health Interview Survey (NHIS)

5. National Health and Nutrition Examination Survey (NHANES)

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

6. National Survey of Children’s Health (NSCH)

We also recommended including and excluding specific survey questions among these 6

surveys. The questions listed in Appendix A are based on these recommendations as well as

comments received from the VEHSS expert panel.

■ Project Step 4. Analyze individual surveys to populate the outcome categories with

single-source estimates

VEHSS analyzed the selected surveys to generate single-source estimates for the categorized

data indicators. The term ‘single source’ refers to estimates derived from a single data source.

The single source estimation step results in public use files (PUFs) which contain high-level

summary results for each individual dataset. The analysis and results of each survey are

documented in separate data analysis reports, and the PUFs are available through the VEHSS

data visualization application and the CDC Open Data platform. The research team also

created research de-identified files (RDF) for datasets that are used internal to the project for

further analysis.

■ Project Step 5. Select individual surveys for inclusion in the statistical integration models to

generate the comprehensive national estimates

In the final VEHSS project step, we build on the single-source estimates by further

harmonizing multiple data sources including surveys, claims, registry, and population-bases

study estimates. This process uses statistical meta-regression models to summarize estimates

derived from the RDFs from multiple sources, and to create sociodemographic group

specific, national and state level prevalence and service utilization rate estimates for selected

vision and eye health data indicators.

This report presents the project plan for utilizing the national surveys to create single-source estimates in

Step 4 above. An overview of the approach to analysis and dissemination is provided. The appendices

contain supporting documentation to further explain how variables are categorized and analyzed.

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

Analysis Plan Outline

This section presents VEHSS’ overall analysis plan which uses the survey question categories, analysis

factor variables, and output data format included in Appendices A-D.

Step 1: Survey Validation and Dataset Preparation

The initial approach to dataset preparation included the following steps:

Review identified variables

Based on publicly available survey documentation, we identified vision and eye health related questions

for each survey, as described in the “Review of National Survey Data on Eye Health Report.” In some

cases, survey documentation was incomplete.

Analysts locate outcome and stratification variables in the data files and confirm the accuracy and

completeness of the survey and survey instrument information in the survey identification report.

Select years of data for analysis

We evaluate survey variable availability by year, sample size and response frequencies to determine

which years of each dataset to analyze, and whether multiple years must be merged to increase the sample

size.

Survey structure, weighting, and denominators

Analysts further review the survey documentation to identify any relevant information such as missing

value coding, skip patterns, and survey weighting. The proper denominator is defined for each survey

instrument.

Internal consistency of questions

Analysts check questions for consistency in measurement and language both within and across surveys.

Checks within surveys included checking skip patterns and the level of contradictory responses among

two or more similar questions. Major internal consistency issues are described in the Survey data analysis

reports for each data source.

Step 2: Define Outcome and Stratification Variables

The next step in survey data analysis is to define the outcome, risk factor, and other stratification

variables. Outcome measures are determined based on the survey question response options, which are

mapped to response options defined by the VEHSS project as part of the categorization schema described

in Appendix A. Over time, survey outcome measures may change due to changes in survey questions, or

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

changes to the VEHSS categorization schema. Outcome measures, stratification variables, and response

values are modeled after the VEHSS Uniform Dataset Template in Appendix B.

Define variable types and responses

Analysts determined if outcome variables and risk factor variables are bivariate or scaled response.

Scaled responses:

We include some scaled response variables as part of the single-source estimates. Scaled responses are

analyzed as proportions, such that all possible responses sum to 100%. Scaled responses therefore include

response values for survey responses such as I don’t know, Missing, Refused, etc.

Bivariate responses:

Bivariate responses are defined as questions with responses primarily consisting of Yes or No. Responses

may also include Refused, Missing, or other responses indicating that the question was not answered.

The VEHSS team considered different options for coding responses for such questions. Currently, only

Yes responses are coded. The denominator of this response includes all respondents who provided a Yes

or No response. Other responses such as Refused or I don’t know were dropped from the denominator.

This approach is based on CDC guidance, and follows their standard practice for reporting proportions

from surveys.

The VEHSS Uniform Dataset Template

The VEHSS Uniform Dataset Template is a standardized data format and data dictionary that ensures that

all data is organized and reported in a consistent manner to support the CDC data visualization

application, the CDC Open Data platform, and the DisMOD-MR statistical integration model. Variable

templates are summarized below, and included in detail in Appendix B.

Race and Sex:

As defined in the VEHSS uniform data template, survey respondents were assigned to mutually exclusive

race/ethnicity and gender categories (Note: the term “gender” is used herein to align with the terminology

used by the CDC data visualization system). If a particular survey did not include all race/ethnicities, this

was noted in the data brief and documentation for that survey.

Age groups:

All surveys were analyzed using:

■ Overall total (all ages)

■ Major Age Groups (0-17, 18-39, 40-64, 65-84, 85+)

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

Survey files included in the statistical integration model use the VEHSS/World Health Organization

(WHO) expanded age groups as noted below (0-1, 1-4, 5-9, 10-14, etc.).

Risk Factors:

The risk factors currently included in the VEHSS survey analyses are diabetes, hypertension, and

smoking. Each risk factor is analyzed independently of the others. Risk factors responses are defined in

the VEHSS Uniform Data Template.

As with eye and vision indicators, risk factor responses may be bivariate or scaled. Bivariate responses

were calculated for Yes, No, Refused/Don’t Know, and Total. Proportions for each level of scaled

responses were calculated and sum to a 100% of total responses. Respondents with missing risk factor

responses were included in the overall analysis.

Analysts coded some risk factors as bivariate to avoid high suppression rates. For example, Smoking was

collapsed into a bivariate response (yes-including current and former, and no-including never) for

NHANES to avoid near universal suppression.

Insurance:

Insurance status was included for integration into RDF results only. Missing insurance was noted, and

respondents with missing insurance responses were included in the overall analysis.

States:

If available, survey results were analyzed by state. Missing states were noted, and respondents with

missing state responses were included in the overall analysis.

Step 3: Estimate Results

Each dataset was analyzed based on the years selected for inclusion.

Data Values

The primary data value is a proportion and reported using a percentage format. For bivariate responses,

this corresponds to the prevalence rate of Yes responses. For scaled responses, the data value is a

proportion of respondents for each scale response value, and all responses sum to 100%.

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

Statistical measures

Based on the recommended standard for calculating small confidence intervals for proportions from the

NCHS, upper and lower confidence intervals and the relative standard error (RSE) were calculated using

the Clopper-Pearson (exact) method.

The respondent sample size are reported for each response.

Age adjustment

The data visualization application allows display of different data types, including ‘crude prevalence’ and

‘age adjusted prevalence’. When included, age adjusted results may use alternative methods for

calculating confidence intervals because of statistical software limitations.

Step 4: Dataset preparation

Summary Table Public Use Files (PUF)

In addition to creating single-source estimates for the VEHSS data visualization application, we also

created summary table PUFs. PUFs do not contain any patient-level records. PUFs are de-identified,

summary data tables which contain prevalence rates, scaled responses, utilization rates, and sample sizes.

The data are summarized across multiple patients and grouped by the different stratification factors

described in Appendix C. All survey, claims, and registry data are formatted into a PUF based on the

VEHSS uniform data template to create individual datasets using the same data structure and a common

set of data identifiers.

The age groups, suppression, and dissemination rules for PUFS are described below:

Age Groups:

Age groups are as follows: 0-17, 18-39, 40-64, 65-84, 85+.

Suppression:

The data suppression rules are:

■ Suppress rate only if RSE >30%

Footnote: “**Some values are suppressed due to a relative standard error >30%”

■ Suppress rate and sample size if sample size < 30

Footnote: “*Some values are suppressed due to a sample size <30”

■ Suppress rate and sample size if both

Parker JD, Talih M, Malec DJ, et al. National Center for Health Statistics Data Presentation Standards for Proportions. National

Center for Health Statistics. Vital Health Stat 2(175). 2017

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

Footnote: “***Some values are suppressed due to a sample size<30 and a relative standard

error >30%”

Suppressed rows remain in the PUF, with footnotes indicating the reason for suppression. This

suppression algorithm was developed based in part on a review of common suppression algorithms for

health data from sample survey results and population count systems in use by Healthy People 2010, as

well as current CDC Vision Health Initiative (VHI) practice.

†

Dissemination:

PUFs are loaded onto the CDC Open Data platform or housed on a separate secure server. If a data

provider does not want the actual PUF to be accessible to the public, the PUF can be housed on a separate

secure server. The data visualization application can still query the data, but only do so for one data point

at a time. This effectively prevents users from obtaining or recreating the full dataset. Currently, all

survey PUFs are loaded onto the CDC Open Data Platform.

Stratifications:

Because the data visualization application displays lines of data, but does not perform calculations, every

possible combination of stratification variables that is displayed in the data visualization application was

previously specified in the PUF table. For each state/national level, there are 24 potential combinations of

stratification factors as detailed in Appendix D. Stratification factors include:

■ Age (age group)

■ Race (race/ethnicity)

■ Gender

■ Risk Factor, and

■ State/national location

Not all combinations are included in the PUF data. The drop-down menu options in the data visualization

application are data driven. If a combination of factors is not in the PUF, then users are not given this

option. Stratification level decisions for each dataset are made on a case by case basis. Where possible,

we include all stratifications unless it results in exceptionally high missing or suppressed rates. Specifics

are provided in the individual survey data reports. For example, in the ACS we included all state level

stratifications. In contrast, for NSCH, we included all stratification levels for national results only. For

state level NSCH results, we found that >90% of the results were missing/suppressed, and therefore, we

decided to only include single-level stratification at the state level.

†

Klein RJ, Proctor SE, Boudreault MA, Turczyn KM. Healthy People 2010 criteria for data suppression. Statistical Notes, no 24.

Hyattsville, Maryland: National Center for Health Statistics. June 2002. Available at:

https://www.cdc.gov/nchs/data/statnt/statnt24.pdf

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

Disseminating Results and Statistics

Data Reports

Preliminary results and statistics from each PUF dataset are compiled into summary data reports, with

tables and figures depicting results for each outcome by each available stratification factor (age group,

race/ethnicity, gender, risk factor, state) . Reports include the elements described below.

Dataset description

We provide a description of the survey, including:

■ Purpose and Scope

■ Sample Design

■ Data Collection Procedures

Analysis Process

We document the analysis procedures, including any issues encountered during analysis. For example, we

describe issues with missing data or issues with data quality for internal consistency.

■ Analysis Overview

■ Analysis Variables

Data Dictionary and Classification to VEHSS Indicators

We outline the variables reported in the analysis based on the VEHSS Uniform dataset template.

Table 1. Example Data Dictionary Table

NSCH

VEHSS

Indicator

Topic

VEHSS

Indicator

Category

NSCH

Variable

Name

Years

Available Question Response Options

Visual

Function

Difficulty

Seeing with

Glasses

K2Q44A

2007,

2011/2012

Has a doctor or other health care

provider ever told you that

[CHILD] had vision problems that

cannot be corrected with glasses

or contact lenses?

1 Yes

2 No

Visual

Function

Vision

Impairment

K2Q44C

2007,

2011/2012

Would you describe [his/her]

vision problems as mild,

moderate, or severe?

1 Mild

2 Moderate

3 Severe

4 Don’t Know

5 Refused

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

Validation Results

We provide a review and description of the survey sample sizes, number of cells suppressed, initial data

quality checks, and other validation steps.

Summary Outcome measures:

Data tables are created to include the rate, 95% confidence interval of the rate, and the sample size for

each indicator. Indicators are reported by single level stratifications (*when available) by:

■ Age group

■ Race/ethnicity

■ Gender

■ Risk factor*

■ State*

■ Insurance*

Table 2. Example Summary Outcome Table

Gender Prevalence Rate Sample Size

Male

1.9 (1.6-2.2) 49,163

Female

1.6 (1.3-1.8) 46,292

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

Appendix A. Categorization Schema for National Survey

Variables

The proposed 2-level categorization schema for the chosen national survey questions, based on general

topics and categories, is presented below.

■ Eye Health Conditions

► Cataract

► Diabetic Retinopathy

► Glaucoma

► Age Related Macular Degeneration

■ Visual Function

► Blind or severe difficulty seeing

► Difficulty seeing with glasses

► Near-sightedness

► Far-sightedness

► Vision correction

► Vision impairment

■ Service Utilization

► Exam with dilation

► Refractive correction

► Cataract surgery

■ Insurance Coverage and Costs

► Insurance

■ Examination Measures

► Visual acuity

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

Table 3. Overview of Surveys and TOPICS

Topics

Total

Topics per

Survey

Eye

Conditions

Visual

Function

Service

Utilization

Examination

Measures

Surveys

ACS • 1

BRFSS • • • 3

MCBS • • • 3

NHANES • • • • 4

NHIS • • • 3

NSCH • 1

Total Surveys per Topic 4 6 4 1

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

Survey Questions for Analysis

The table below presents the questions chosen for analysis. The ‘Topic’ and ‘Category’ columns show the 2-level categorization described above

for each question. Information presented in the ‘Variable Name’, ‘Years Available’, ‘Question’, and ‘Response Options’ columns was collected

from each survey’s publicly available official documentation. The final column, ‘Response ID’, indicates the name assigned by NORC to each

response option for analysis. Bivariate responses were reported as prevalence rates and coded with ‘yes’ or ‘no’ responses. Other possible

responses such as ‘missing’, ‘don’t know’ or ‘refused’ were not coded in the PUF single-source estimates because these values are not displayed in

the data visualization application, and because in initial testing, such responses were suppressed in all cases.

Table 4. Survey questions included in analysis

ACS

Topic Category

Variable

Name

Years

Available

(analyzed) Question Response Options

Visual

Function

Difficulty seeing

with glasses

DIFFEYE 2008-2016

(2014, 2015)

Is this person blind or does he/she have serious

difficulty seeing even when wearing glasses?

1 Yes

2 No

0 Not applicable

BRFSS

Topic Category

Variable

Name

Years

Available

(analyzed) Question Response Options

Demographics Core Section

Visual

Function

Difficulty seeing

with glasses

BLIND 2013-2016

(2016)

Are you blind or do you have serious difficulty seeing,

even when wearing glasses?

1 Yes

2 No

7 Don’t know / Not sure

9 Refused

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

NHANES

Topic Category

Variable

Name

Years

Available

(analyzed) Question Response Options

Service

Utilization

Cataract

Surgery

VIQ070,

VIQ071

1999- 2008

(2005-2008

merged)

{Have you/Has SP} ever had a cataract operation?

1 Yes

2 No

7 Refused

9 Don't know

Visual

Function

Blind or Severe

Difficultly

Seeing

VIQ017 2005-2008

(2005-2008

merged)

{Are you/Is SP} blind in both eyes? 1 Yes

2 No

7 Refused

9 Don't know

Eye Health

Conditions

Self-report

glaucoma

VIQ090 2005-2008

(2005-2008

merged)

{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?

1 Yes

2 No

7 Refused

9 Don't know

Eye Health

Conditions

Self-report age

related macular

degeneration

VIQ310 2005-2008

(2005-2008

merged)

{Have you/Has SP} ever been told by an eye doctor

that {you have/s/he has} age-related macular (mac-u-

lar) degeneration?

1 Yes

2 No

7 Refused

9 Don't know

Eye Health

Conditions

Self-report

diabetic

retinopathy

DIQ080 1999-2014

(2005-2008

merged)

Has a doctor ever told {you/SP} that diabetes has

affected {your/his/her} eyes or that {you/s/he} had

retinopathy (ret-in-op-ath-ee)?

1 Yes

2 No

7 Refused

9 Don't know

Eye Health

Conditions

Exam-based

glaucoma

OPXDGLAU,

OPXSGLAU

2005-2008

(2005-2008

merged)

Calculated based on patient’s retinal image in right or

left eye has features suggestive of glaucoma

Yes

Eye Health

Conditions

Exam-based

age related

macular

degeneration

Opduarm,

opdud125,

opduga,

opduexu

2005-2008

(2005-2008

merged)

This field is coded for the presence or absence of any

retinopathy, Left, Right or Worse Eye

Yes

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

NHANES

Topic Category

Variable

Name

Years

Available

(analyzed) Question Response Options

Eye Health

Conditions

Exam-based

diabetic

retinopathy

diq010, lbxgh,

diq080,

opduret

2005-2008

(2005-2008

merged)

Calculated based among patients with self-report or

exam diagnosed diabetes, and levels of retinopathy

severity, Left, Right or Worse eye.

Yes

Visual Acuity

Measures

Visual acuity

vidrova

vidlova

1999-2008

(2005-2008

merged)

Best-corrected visual acuity Normal vision

Any vision loss (≤20/32 in better eye)

Visual impairment (20/32 - 20/160 in

better eye)

Visual impairment (20/32 - 20/63 in

better eye)

Visual impairment (20/70 - 20/160 in

better eye)

US blind (≤20/200 in better eye)

Monocular vision loss (≤20/70 in either

eye)

Missing acuity

Visual Acuity

Measures

Visual acuity

vidrova

vidlova

1999-2008

(2005-2008

merged)

Best-corrected visual acuity Normal vision

Any vision loss (≤20/32 in better eye)

Visual impairment (20/32 - 20/160 in

better eye)

Visual impairment (20/32 - 20/63 in

better eye)

Visual impairment (20/70 - 20/160 in

better eye)

US blind (≤20/200 in better eye)

Monocular vision loss (≤20/70 in either

eye)

Missing acuity

Visual Acuity

Measures

Visual acuity

vidrova

vidlova

vidrova

vidlova

1999-2008

(2005-2008

merged)

Uncorrected Refractive Error (URE) Yes

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

NHIS

(NOTE: Years Available are based on IPUMS database)

Topic Category

Variable

Name

Years

Available

(analyzed) Question Response Options

Adult Questionnaire

Visual

Function

Blind or Severe

Difficulty Seeing

ABLIND

1999-2016

(2014-2015

merged)

Are you blind or unable to see at all?

1 Yes

2 No

7 Refused

9 Don't know

Visual

Function

Difficulty Seeing

with Glasses

AVISION

1999-2016

(2014-2015

merged)

Do you have any trouble seeing, even when wearing

glasses or contact lenses?

1 Yes

2 No

7 Refused

8 Not ascertained

9 Don't know

Functioning and Disability Questionnaire

Visual

Function

Difficulty Seeing

with Glasses

VIS_SS

2011-2016

(2014-2015

merged)

Do you have difficulty seeing, even when wearing

glasses?

1 No difficulty

2 Some difficulty

3 A lot of difficulty

4 Cannot do at all/unable to do

7 Refused

9 Don't know

Visual

Function

Vision

Correction

VIS_0

2012-2016

(2014-2015

merged)

Do you wear glasses? 1 Yes

2 No

7 Refused

9 Don't know

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

NHIS

(NOTE: Years Available are based on IPUMS database)

Topic Category

Variable

Name

Years

Available

(analyzed) Question Response Options

Child Questionnaire

Visual

Function

Blind or Severe

Difficulty Seeing

CBLIND

1999-2016

(2014-2015

merged)

Is [fill: S.C. name] blind or unable to see at all? 1 Yes

2 No

7 Refused

8 Not ascertained

9 Don't know

Visual

Function

Difficulty Seeing

with Glasses

CVISION

1999-2016

(2014-2015

merged)

Does [fill1: S.C. name] have any trouble seeing [fill2: ,

even when wearing glasses or contact lenses]?

1 Yes

2 No

7 Refused

8 Not ascertained

9 Don't know

NSCH

Topic Category

Variable

Name

Years

Available Question Response Options

Visual

Function

Difficulty Seeing

with Glasses

K2Q44A

2007,

2011/2012

(2007/2011/201

2 merged)

Has a doctor or other health care provider ever told

you that [CHILD] had vision problems that cannot be

corrected with glasses or contact lenses?

1 Yes

2 No

NORC | Survey Analysis Plan: Vision & Eye Health Surveillance System

Appendix B. VEHSS Uniform Data Table Template

Table 5. VEHSS Uniform Data Table Template

Source Column Description Data Type

YearStart

Starting Year for year range number

YearEnd

Ending Year for year range, same as starting year if single year used in evaluation. number

LocationAbbr

State Abbreviation plain text

LocationDesc

State Name plain text

DataSource

Abbreviation of Data Source plain text

Topic

Topic description plain text