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NDAR provides a single access to de-identified autism research data. For permission to download data, you will need an NDAR account with approved access to NDAR or a connected repository (AGRE, IAN, or the ATP). For NDAR access, you need to be a research investigator sponsored by an NIH recognized institution with federal wide assurance. See Request Access for more information.

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This is a U.S. Government computer system, which may be accessed and used only for authorized Government business by authorized personnel. Unauthorized access or use of this computer system may subject violators to criminal, civil, and/or administrative action. All information on this computer system may be intercepted, recorded, read, copied, and disclosed by and to authorized personnel for official purposes, including criminal investigations. Such information includes sensitive data encrypted to comply with confidentiality and privacy requirements. Access or use of this computer system by any person, whether authorized or unauthorized, constitutes consent to these terms. There is no right of privacy in this system.

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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

Value Range
Data Structures with shared data
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Letter Comparison Test



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
lct1IntegerRecommendedYCX __YMX1;21=Same; 2=Different
lct2IntegerRecommendedHTRBDP __HTRBDP1;21=Same; 2=Different
lct3IntegerRecommendedLNDPRSKQB __LNDPRSJQB1;21=Same; 2=Different
lct4IntegerRecommendedHCF __RCF1;21=Same; 2=Different
lct5IntegerRecommendedQTPRJX __QTPNJX1;21=Same; 2=Different
lct6IntegerRecommendedMZDYGVGKQ __MZDYGLBKQ1;21=Same; 2=Different
lct7IntegerRecommendedFQTNMK __JQTNMK1;21=Same; 2=Different
lct8IntegerRecommendedCLJ __CLJ1;21=Same; 2=Different
lct9IntegerRecommendedJGDMNSVPW __JGZMNSVPW1;21=Same; 2=Different
lct10IntegerRecommendedFPTVHKCBJ __FPTVHKCBJ1;21=Same; 2=Different
lct11IntegerRecommendedXRPZBS __ZRPZBH1;21=Same; 2=Different
lct12IntegerRecommendedZSQ __ZSP1;21=Same; 2=Different
lct13IntegerRecommendedMPZRXL __MPZRXL1;21=Same; 2=Different
lct14IntegerRecommendedKJH __KRH1;21=Same; 2=Different
lct15IntegerRecommendedSMNHVTFCB __SMNHVTFCB1;21=Same; 2=Different
lct16IntegerRecommendedKJWTQF __KJWTQF1;21=Same; 2=Different
lct17IntegerRecommendedCHDKQGLMB __CHDKQGLMB1;21=Same; 2=Different
lct18IntegerRecommendedGHQ __GHQ1;21=Same; 2=Different
lct19IntegerRecommendedGFVMRH __GFVMRH1;21=Same; 2=Different
lct20IntegerRecommendedRSM __RSM1;21=Same; 2=Different
lct21IntegerRecommendedBSRJTRMLG __BSFJTRMLG1;21=Same; 2=Different
lct22IntegerRecommendedNBGFSM __NBGFSM1;21=Same; 2=Different
lct23IntegerRecommendedJQKBPLXGY __JQKBPLXGY1;21=Same; 2=Different
lct24IntegerRecommendedRNV __FNV1;21=Same; 2=Different
lct25IntegerRecommendedPRDBZTYFN __PRDBZTYFN1;21=Same; 2=Different
lct26IntegerRecommendedNCWJDZ __NCMJDZ1;21=Same; 2=Different
lct27IntegerRecommendedKHW __KBW1;21=Same; 2=Different
lct28IntegerRecommendedZRBGMF __ZRBCMF1;21=Same; 2=Different
lct29IntegerRecommendedBTH __BYH1;21=Same; 2=Different
lct30IntegerRecommendedXWKQRYCNZ __XWKQRYCNZ1;21=Same; 2=Different
lct31IntegerRecommendedHNPDLK __HNPDLK1;21=Same; 2=Different
lct32IntegerRecommendedWMQTRSGLZ __WMQTRZGLZ1;21=Same; 2=Different
lct33IntegerRecommendedJPN __JPN1;21=Same; 2=Different
lct34IntegerRecommendedQLXSVT __QLNSVT1;21=Same; 2=Different
lct35IntegerRecommendedYXHKZVFPB __YXHKZVFPD1;21=Same; 2=Different
lct36IntegerRecommendedRJZ __RJZ1;21=Same; 2=Different
lct37IntegerRecommendedCLNPZD __CLNPZD1;21=Same; 2=Different
lct38IntegerRecommendedDCBPFHXYJ __DCBPFHXYJ1;21=Same; 2=Different
lct39IntegerRecommendedMWR __ZWR1;21=Same; 2=Different
lct40IntegerRecommendedLPKXZW __LPKXZW1;21=Same; 2=Different
lct41IntegerRecommendedTZL __TZQ1;21=Same; 2=Different
lct42IntegerRecommendedCSDBFPHXZ __CSDBFPHXZ1;21=Same; 2=Different
lct43IntegerRecommendedQHZXPC __QHZWPC1;21=Same; 2=Different
lct44IntegerRecommendedGZN __GZN1;21=Same; 2=Different
lct45IntegerRecommendedJNWXHPFBD __JNWXHPFMD1;21=Same; 2=Different
lct46IntegerRecommendedTotal number of correct items
evt_totalIntegerRecommendedTotal Number of incorrect items
lct48IntegerRecommendedLetter Comparison Test score
letter_total_pg1IntegerRecommendedLetter total pg1letter1
letter_total_pg2IntegerRecommendedLetter total pg2letter2
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: lct01 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.