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ABCD Youth Snellen Vision Screener (SVS)

11,877 Shared Subjects

Vision screening
Clinical Assessments
Phys Exam
View Change History
Query Element Name Data Type Size Required Condition Description Value Range Notes Aliases
subjectkey GUID Required The NDAR Global Unique Identifier (GUID) for research subject NDAR*
src_subject_id String 20 Required Subject ID how it's defined in lab/project
interview_date Date Required Date on which the interview/genetic test/sampling/imaging/biospecimen was completed. MM/DD/YYYY
interview_age Integer Required Age in months at the time of the interview/test/sampling/imaging. 0 :: 1260 Age is rounded to chronological month. If the research participant is 15-days-old at time of interview, the appropriate value would be 0 months. If the participant is 16-days-old, the value would be 1 month.
sex String 20 Required Sex of subject at birth M;F; O; NR M = Male; F = Female; O=Other; NR = Not reported gender
eventname String 60 Required The event name for which the data was collected
Query snellen_aid_y Integer Recommended Do you wear any necessary corrective aids (glasses, contacts)? 1 ; 0 1 = Yes; 0 = No; Starting from the top of the chart, please read aloud one row at a time from left to right until I tell you to stop. If needed, say Keep going. snellen_aid
Query snellen_aidpres_y Integer Recommended snellen_aid_y == 1 Are you wearing them now? Ensure subject is wearing them) 1 ; 0 1 = Yes; 0 = No; Starting from the top of the chart, please read aloud one row at a time from left to right until I tell you to stop. If needed, say Keep going. snellen_aidpres
Query snellen_va_y Integer Recommended 1. Ensure that the chart is located in a well lit area and readily readable. 2. Verify if the child has corrective lenses and if so, whether he or she is wearing them. 3. Ascertain whether h/she can appropriately respond to stimuli on an iPad screen. Smallest line subject was able to see without error? Line numbers are represented on the right-most side of the chart. 0 ; 1 ; 2 ; 3 ; 4 ; 5 ; 6 ; 7 ; 8 ; 9 ; 10 ; 11 0 = Can't read line 1; 1 = Line 1; 2 = Line 2; 3 = Line 3; 4 = Line 4; 5 = Line 5; 6 = Line 6; 7 = Line 7; 8 = Line 8; 9 = Line 9; 10 = Line 10; 11 = Line 11 // Users should consider variations in visual status (Snellen) before analyzing the neurocognition data. Many children have scores indicating poor vision. snellen_va
Query vis_flg Integer Recommended snellen_va_y == 4 || snellen_va_y == 3 || snellen_va_y == 2 Can the participant read the stimuli on the iPad? 1 ; 2 1 = YES = proceed with testing; 2 = NO = stop testing snellen_flg
Data Structure

This page displays the data structure defined for the measure identified in the title and structure short name. The table below displays a list of data elements in this structure (also called variables) and the following information:

  • Element Name: This is the standard element name
  • Data Type: Which type of data this element is, e.g. String, Float, File location.
  • Size: If applicable, the character limit of this element
  • Required: This column displays whether the element is Required for valid submissions, Recommended for valid submissions, Conditional on other elements, or Optional
  • Description: A basic description
  • Value Range: Which values can appear validly in this element (case sensitive for strings)
  • Notes: Expanded description or notes on coding of values
  • Aliases: A list of currently supported Aliases (alternate element names)
  • For valid elements with shared data, on the far left is a Filter button you can use to view a summary of shared data for that element and apply a query filter to your Cart based on selected value ranges

At the top of this page you can also:

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  • Download a copy of this definition in CSV format
  • Download a blank CSV submission template prepopulated with the correct structure header rows ready to fill with subject records and upload

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