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Selected Filters
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The filters you have selected from various query interfaces will be stored here, in the 'Filter Cart'. The database will be queried using filters added to your 'Filter Cart', when multiple filters are defined, each will be executed using 'AND' logic, so with each filter that is applied the result set gets smaller.

From the 'Filter Cart' you can inspect each of the filters that have been defined, and you also have the option to remove filters. The 'Filter Cart' itself will display the number of filters applied along with the number of subjects that are identified by the combination of those filters. For example a GUID filter with two subjects, followed by a GUID filter for just one of those subjects would return only data for the subject that is in both GUID filters.

If you have a question about the filter cart, or underlying filters please contact the help desk at The NDA Help Desk

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Data Structures with shared data
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Knee X-Ray Joint Space Width Measurements



Download Definition as
Download Submission Template as
Element NameData TypeSizeRequiredDescriptionValue RangeNotesAliases
subjectkeyGUIDRequiredThe NDAR Global Unique Identifier (GUID) for research subjectNDAR*
src_subject_idString20RequiredSubject ID how it's defined in lab/project
interview_dateDateRequiredDate on which the interview/genetic test/sampling/imaging/biospecimen was completed. MM/DD/YYYYRequired field
interview_ageIntegerRequiredAge in months at the time of the interview/test/sampling/imaging.0 :: 1260Age 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.
genderString20RequiredSex of the subjectM;FM = Male; F = Female
visitString50RecommendedVisit nameCharacter description of each type of visit
sideIntegerRecommendedside0::30= neither;1=left; 2=right; 3=bilateral
versionString20RecommendedVersion/code of assessment
file_sourceString1,024RecommendedFile name/location
barcdbuString20Recommendedbarcode of image analyzedbarcdjd
cfwdthFloatRecommendedwidth of femoral condyles used to define x=1.0 [mm]
mcmjswFloatRecommendedkXR reading (JD): medial minimum JSW [mm]
jsw175FloatRecommendedmedial JSW at x=0.175 [mm]
jsw200FloatRecommendedmedial JSW at x=0.200 [mm]
jsw250FloatRecommendedmedial JSW at x=0.250 [mm]
jsw300FloatRecommendedmedial JSW at x=0.300 [mm]
jsw225FloatRecommendedmedial JSW at x=0.225 [mm]
tpcfdsFloatRecommendeddistance from tibial plateau to tibial rim closest to femoral condyle [mm]
bmangFloatRecommendedx- ray beam angle from Synaflexer phantom [degrees]
jsw150FloatRecommendedmedial JSW at x=0.150 [mm]
jsw275FloatRecommendedmedial JSW at x=0.275 [mm]
ljsw850FloatRecommendedlateral JSW at x=0.850 [mm]
ljsw900FloatRecommendedlateral JSW at x=0.900 [mm]
ljsw700FloatRecommendedlateral JSW at x=0.700 [mm]
ljsw825FloatRecommendedlateral JSW at x=0.825 [mm]
ljsw750FloatRecommendedlateral JSW at x=0.750 [mm]
ljsw875FloatRecommendedlateral JSW at x=0.875 [mm]
ljsw725FloatRecommendedlateral JSW at x=0.725 [mm]
ljsw775FloatRecommendedlateral JSW at x=0.775 [mm]
ljsw800FloatRecommendedlateral JSW at x=0.800 [mm]
xmjswFloatRecommendedx coordinate of minimum JSW
incpllIntegerRecommendedincomplete delineation of lateral compartment - some JSW(x) set to .T0;10=No; 1=Yes
incplmIntegerRecommendedincomplete delineation of medial compartment - some JSW(x) set to .T0;10=No; 1=Yes
nommjswIntegerRecommendedmedial mJSW cannot be measured due to poor positioning, image quality or other reason0;10=No; 1=Yes
noljswxIntegerRecommendedlateral JSW(x) cannot be measured due to poor positioning or poor image quality0;10=No; 1=Yes
mjswbbIntegerRecommendedmJSW is set to zero, used when reader judges bone on bone in medial compartment0;10=No; 1=Yes
incstpsIntegerRecommendedinconsistent positioning at one or more visits based on rim distance0;10=No; 1=Yes
ltpmebeIntegerRecommendedlateral tibial plateau margin is the same as the bone edge0;10=No; 1=Yes
nomjswxIntegerRecommendedmedial JSW(x) cannot be measured due to poor positioning or poor image quality0;10=No; 1=Yes
nolminIntegerRecommendedmedial mJSW measured but there is no local minimum0;10=No; 1=Yes
impixszFloatRecommendedpixel size used for convertion from pixel units to millimetres (uncorrected for magnification of knee) [mm]
ageyearsIntegerRecommendedAge in years
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:

  • Use the search bar to filter the elements displayed. This will not filter on the Size of Required columns
  • 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

Please email the The NDA Help Desk with any questions.

Distribution for DataStructure: kxrqjsw01 and Element:
Chart Help

Filters enable researchers to view the data shared in NDA before applying for access or for selecting specific data for download or NDA Study assignment. For those with access to NDA shared data, you may select specific values to be included by selecting an individual bar chart item or by selecting a range of values (e.g. interview_age) using the "Add Range" button. Note that not all elements have appropriately distinct values like comments and subjectkey and are not available for filtering. Additionally, item level detail is not always provided by the research community as indicated by the number of null values given.

Filters for multiple data elements within a structure are supported. Selections across multiple data structures will be supported in a future version of NDA.