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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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After Study Knowledge Questionnaire



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Element NameData TypeSizeRequiredDescriptionValue RangeNotes
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
siteString100RecommendedSiteStudy Site
daysrzIntegerRecommendeddays since randomization
visitString50RecommendedVisit nameCharacter description of each type of visit
completedIntegerRecommendedChecks if completed0::30=No; 1=Yes; 2=Yes, lost; 3=Unverified
ci_enrolledIntegerRecommendedParticipant enrolled0;10=No; 1=Yes
relationshipIntegerRecommendedRelationship of respondent to individual
1::88; 90;-999
1 = Biological mom; 2 = Biological dad; 3 = Grandparent; 4 = Special education (sped) teacher; 5 = General education teacher; 6 = Occupational therapist; 7 = Speech and language therapist; 8 = Behavioral therapist; 9 = Paraprofessional; 10 = Aide; 11 = Principal; 12 = Administrator; 13 = Other; 14 = Content teacher; 15 = Parent center director; 16 = Self; 17=Adoptive mother; 18=Adoptive father; 19=Foster mother; 20 = Foster father; 21=Grandmother; 22=Grandfather; 23=Step-mother; 24 = Step-father; 25=Aunt; 26=Uncle; 27=Missing Data; 28=Both parents;31= Grandmother from mother side; 32= Grandfather from mother side; 33= Grandmother from father side; 34= Grandfather from father side; 36= Brother; 37= Sister; 38= Cousin; 39= female caregiver; 40=male caregiver; 41=Female child; 42=Male child; 43=Spouse/Mate; 44=Friend; 45=Parent; 46=Significant other; 47=Sibling; 48=Son/Daughter; 49=Son-in-law/Daughter-in law; 50=Other Relative; 51=Paid caregiver; 52=Friends; 53=Roommate; 54=Supervisor; 55=mother's boyfriend; 56=other parental figure; 57=Summary; 58=counselor ; 59 = other female relative; 60 = other male relative; 61 = non-relative ; 62=Maternal Aunt; 63=Maternal Uncle; 64=Maternal Cousin; 65 = Paternal Aunt; 66=Paternal Uncle; 67=Paternal Cousin ; 68=Biological/Adoptive Mother and Grandmother; 69=Biological/Adoptive Mother and Stepmother and Grandmother; 70=Biological/Adoptive Mother and Grandmother and Foster Father; 71=Biological/Adoptive Mother and Stepmother and Foster Mother; 72=Biological/Adoptive Mother and Foster Mother; 73=Biological/Adoptive Mother and Biological/Adoptive Father; 74=Biological/Adoptive Mother and Stepmother and Biological/Adoptive Father; 75=Biological/Adoptive Mother and Other; 76=Biological/Adoptive Mother and Stepmother and Stepfather; 77=Biological/Adoptive Mother and Stepfather; 78=Biological/Adoptive Mother and Grandfather; 79=Biological/Adoptive Mother and Stepmother and Foster Father; 80=Biological/Adoptive Mother and Stepmother; 81=Guardian, female; 82=Other female; 83=Guardian, male; 84=Other male; 85=Other/Grandparent/Nanny; 86 = Mother, Father, Guardian; 87 = Daughter, son, grandchild; 88 = Professional (e.g., social worker, nurse, therapist, psychiatrist, or group home staff); 90=Other; -999=Missing
bkgrnd_educationString1,020RecommendedSubject's education (school and preschool)
afterstdy_q05IntegerRecommendedMain goal of doctors1::5;91 = To find out if a certain medication helps children with autism; 2 = To give free care to children with autism; 3 = To give a medication that is available only in research studies.; 4 = To see if Parent Management Training will produce gains over and above those seen with [medication]; 5 = To find out if medication only helps children with autism
stpnm1String250RecommendedStudy med name1
afterstdy_q07IntegerRecommendedInformed before child received med.1::4;91 = I was informed by the study doctor(s) and/or other staff of what this study is about and my questions were adequately answered; 2 = There was no information available on the study; 3 = The study doctor(s) or other staff didn't inform me, but I found information elsewhere; 4 = I was told that the purpose needed to be a secret for the study to "work right
afterstdy_q08IntegerRecommendedPermission before child received med.1::4;91 = Nobody asked me permission to start the study; 2 = I gave only verbal permission to the study staff to enter him/her into the study; 3 = I gave written permission to the study staff to enter him/her into the study; 4 =The study staff members said that permission was assumed, because I would not have to come ...
afterstdy_q09IntegerRecommendedIn this study...1::4;91 = Some children were given "real" medication and other children "inactive" medication (also called placebo) for 2 months; 2 = All children were given "real" medication for 2 months; 3 = All children were given "inactive" medication for 2 months before they could receive "real medication" ; 4 = no medication is involved
afterstdy_q10IntegerRecommended...the chance of being assigned placebo1::4;91 = 0%; 2 = 50%; 3 = 75%; 4 = 100%
afterstdy_q11IntegerRecommendedWhen the study started...1::4;91 = Some children were given "real" medication and other children "inactive" medication (also called placebo) for 2 months; 2 = All children were given "real" medication for 2 months; 3 = All children were given "inactive" medication for 2 months before they could receive "real medication" ; 4 = no medication is involved
afterstdy_q12IntegerRecommendedBefore start, risks/benefits...1::4;91 = I understood that there were only advantages and benefits, but no risks at all, in participation in the study; 2 = I understood that there were both possible advantages (benefits) and risks, and the doctors told me which the main risks were.; 3 = I was not informed of any benefits or risks possibly associated with this study; 4 = I was told that there were no possible benefits for my child
afterstdy_q13IntegerRecommendedSide effects1::5;91 = Dizziness, abnormal movements of the head or neck, weight gain; 2 = Hair loss, anemia, weight loss; 3 = Diarrhea, vomiting, and heart problems; 4 = Ringing in the ears and coldness in the extremitites (hands and feet); 5 = Craving for salt, reduced appetite, and sweating
afterstdy_q14IntegerRecommendedAt the time I agreed, study med1::4;91 = I was informed of the possible alternatives for treatment; 2 = I understood that there were no alternatives besides the study; 3 = The study medicine was not available yet outside the study; 4 = Parent Management Training has already been proven effective to cure autism
afterstdy_q15IntegerRecommendedAfter consent, drop out was...1::4;91 = It was not possible for my child to drop out of the study before it was completed, even if I wanted him to stop; 2 = I could have taken my child off the study at any time, if I wanted, even if the study was yet not finished; 3 = My child could have stopped the study but only with the permission of the study doctors; 4 = Leaving the study would have resulted in loss of all services at this Medical Center
afterstdy_q16IntegerRecommendedIf dropout, treatment would...1::91 = My child would have to wait for medical care until the study is completed; 2 = My child could not have been treated with the type of medication that is given in this study; 3 = My child would have continued treatment with another doctor; 4 = My child would have to wait for Parent Management Training until the study is completed; 5 = My child could not receive the treatments that are given in this study; 6 = My child could have received these treatments with other therapists in the community; 7 = Parent Management Training would be made available free
afterstdy_q17IntegerRecommendedStudy treatment assignment1::5;91 = Randomly (that is by the tossing of a coin); 2 = By the child; 3 = Based on the individual needs of each child to ensure that each child received the best possible treatment for his/her condition; 4 = Based on the child's age; 5 = Based on the Treatment Preference Form that I completed at the beginning
relation_specifyString20RecommendedRelation Other Specify
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
ques6IntegerRecommendedWhen I agreed to my child's participation in this study, the chance of his/her being assigned to receive only medication (no Parent Management Training) for the 6-month duration of the study was:1::4;91 = 0%; 2 = 33%; 3 = 50%; 4 = 100%
ques10IntegerRecommendedA possible risk or disadvantage of the Parent Management Training is:1::4;91 = that it would result in punishment to my child; 2 = that it would require a lot of time and effort; 3 = that it would involve spoiling my child with bribes; 4 = I would have to spend a lot of money to make it work
ques15IntegerRecommendedBefore I stated in this study, I knew that, If I were assisgned to the medication + therapy group:1::4;91 = his/her teacher would have to give rating every two weeks for my child to stay in the study; 2 = I would have homework to do most weeks; 3 = The behavior therapist would visit out home whenever we needed him/her; 4 = Even if the medicine does not help, my child would have to continue it
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: askq01 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.