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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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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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Alzheimer's Disease Assessment Scale Cognitive Subscale



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Element NameData TypeSizeRequiredDescriptionValue RangeNotesAliases
subjectkeyGUIDRequiredThe NDAR Global Unique Identifier (GUID) for research subjectNDAR*
src_subject_idString20RequiredSubject ID how it's defined in lab/projectcatieid
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
adas01aIntegerRecommendedWorld Recall Trial 10::10number of errors
adas01bIntegerRecommendedWorld Recall Trial 20::10number of errors
adas01cIntegerRecommendedWorld Recall Trial 30::10number of errors
adas02IntegerRecommendedNaming Objects0::50 = 0-2 items, 1 = 3-5 items, 2 = 6-8 items, 3 = 9-11 items, 4 = 12-14 items, 5 = 15-17 items
adas03IntegerRecommendedCommands Score0::51 = 1 command incorrect / 4 commands correct 2 = 2 commands incorrect / 3 commands correct 3 = 3 commands incorrect / 2 commands correct 4 = 4 commands incorrect / 1 command correct 5 = all 5 commands incorrect
adas04IntegerRecommendedConstructional Praxis Score0::50 = all 4 drawn correctly 1 = 1 form drawn incorrectly 2 = 2 forms drawn incorrectly 3 = 3 forms drawn incorrectly 4 = 4 forms drawn incorrectly 5 = no figures, scribbles; parts of forms; words
adas05IntegerRecommendedIdeational Praxis Score0::50 = all components performed correctly 1 = failure to perform 1 component 2 = failure to perform 2 components 3 = failure to perform 3 components 4 = failure to perform 4 components 5 = failure to perform 5 components
adas06IntegerRecommendedOrientation Score0::8Number of incorrect responses
adas07aIntegerRecommendedWorld Recognition Trial 10::12number of errors
adas07bIntegerRecommendedWorld Recognition Trial 20::12number of errors
adas07cIntegerRecommendedWorld Recognition Trial 30::12number of errors
adas08IntegerRecommendedRemembering Test Instructions0::50 = patient never needs reminders of instructions 1 = very mild � forgets once 2 = mild � must be reminded 2 times 3 = moderate � must be reminded 3 or 4 times 4 = moderately severe � must be reminded 5 or 6 times 5 = severe � must be reminded 7 or more times
adas09IntegerRecommendedSpoken Language Ability0::50 = no instances where it is difficult to understand patient 1 = very mild � one instance of lack of understandability 2 = mild � patient has difficulty less than 25% of the time 3 = moderate � patient has difficulty less than 25-50% of the time 4 = moderately severe � patient has difficulty less than 50% of the time 5 = severe � one or two word utterance; fluent, but empty speech; mute
adas10IntegerRecommendedWord-Finding Difficulty in Spontaneo0::50 = no evidence of word finding difficulty in spontaneous speech 1 = very mild � 1 or 2 instances, not clinically significant 2 = mild � noticeable circumlocution or synonym substitution 3 = moderate � loss of words without compensation on occasion 4 = moderately severe � frequent loss of words without compensation 5 = severe � nearly total loss of content of words; speech sounds empty; 1-2 word utterances
adas11IntegerRecommendedComprehension of Spoken Language0::50 = no evidence of poor comprehension 1 = very mild � 1 or 2 instances of misunderstanding 2 = mild � 3-5 instances of misunderstanding 3 = moderate � requires several repetitions and rephrasing 4 = moderately severe � patient only occasionally responds correctly; i.e., yes/no 5 = severe � patient rarely responds to questions appropriately, not due to poverty of speech
adas12IntegerRecommendedConcentration/ Distractibility0::100 = none, no evidence of poor concentration or distractibility 1 = very mild, one instance of poor concentration 2 = mild, 2-3 instances of poor concentration/distractibility; signs of restlessness and inattentiveness 3 = moderate, 4-5 instances during interview 4 = moderately severe, poor concentration/distractibility throughout much of interview 5 = severe, extreme difficulty in concentration and extremely distractible, unable to complete tasks; 6 = Is goal-oriented, can maintain interest in tasks; 7 = Slightly distractible, but is goal-oriented and can finish tasks with minimal pressure; 8 = Quite distractible; finishes tasks only with considerable pressure; shows minimal goal-oriented behavior; 9 = Extremely distractible, cannot sustain attention for more than a few seconds, regardless of external pressure; 10 = Never starts or gets involved in anything presented to him and therefore cannot be rated.
adas13IntegerRecommendedNumber Cancellation:0::40number of targets hit
adas14IntegerRecommendedExecutive Function(maze)0::240in seconds
adas_tsFloatRecommendedADAS Total Score0::5000Created variable with 20% missing data rule applied: First, we created 2 intermediate variables: M_RECALL (mean number of words not recalled in the 3 trials): Average of (10-ADAS01A), (10-ADAS01B), (10- ADAS01C). M_RECOG (mean number of words not recognized in the 3 trials): Average of ADAS07A, ADAS07B, ADAS07C. Total score is calculated as follows: Sum of M_RECALL, ADAS02, ADAS03, ADAS04, ADAS05, ADAS06, M_RECOG, ADAS08, ADAS09, ADAS10, ADAS11
visitidIntegerRecommendedMetaTrial Visit IDSystem variable: unique code for each type of visit -use to merge files
visitString50RecommendedVisit nameCharacter description of each type of visit
visnumFloatRecommendedNumeric Visit Number-1.5 = Pre-Screening; -1 = Screening; 0 = Baseline; ## = Visit ## (from 1 to 10); Whole numbers = standard monthly visits; #.001 - #.009 = Unscheduled; #.1 = End of Phase 1; #.2 = End of Phase 2; #.3 = End of Phase 3; #.4 = End of Open Choice Phase; #.5 = End of Study; #.6 = Genetic Analysis; 1000=all visits
phase_ctString20RecommendedCurrent Phase. Phase patient was in at the time of the assessment Phase 4 refers to the follow-up phase.Pre-Rand; Phase 1/1A; Phase 2; Phase 3; Phase 4; Phase 1B; Open-Choice Phase; Screening; Phase 1
last1IntegerRecommendedFlag Last Phase 1/1A Visit1=Yes for all records meeting this criteria
base1IntegerRecommendedFlag Baseline Phase 1/1A Visit1=Yes for all records meeting this criteria
base_tsFloatRecommendedBaseline Total ScoreScare at Phase 1 baselline
c_tsFloatRecommendedChanged from Baseline ADAS Total ScoreChange from Phase 1 baseline
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: adas_cog01 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.