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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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Multimodal Continuous Performance Test – AX version



Cues are displayed on a screen and probes are played through the headphones

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/projectursi
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.
interview_dateDateRequiredDate on which the interview/genetic test/sampling/imaging/biospecimen was completed. MM/DD/YYYYRequired field
genderString20RequiredSex of the subjectM;FM = Male; F = Female
overall_accFloatRecommendedaccuracy (reported as decimal) of responses for the entire task
overall_rtFloatRecommendedmedian reaction time for the entire task
overall_cnt_hitIntegerRecommendedCount of the correct responses across all tasks
overall_cnt_missIntegerRecommendedCount of the number of times no response was detected across all tasks
overall_cnt_incorrIntegerRecommendedCount of the number of incorrect responses across all tasks
cue_a_accFloatRecommendedaccuracy of the responses to "A" cues (target cues)
cue_a_rtFloatRecommendedmedian reaction time for A cues
cue_a_cnt_hitIntegerRecommendedNumber of responses to A cues
cue_a_cnt_missIntegerRecommendedNumber of missed A cues
cue_a_cnt_incorrIntegerRecommendedNumber of inccorect responses to A cues
probe_ax_accFloatRecommendedaccuracy of X probes following A cues (IE target cue followed by the target probe)
probe_ax_rtFloatRecommendedMedian reaction time to X probes following A cues
probe_ax_cnt_hitIntegerRecommendedcount of correct responses to AX probescpt_right_xa
probe_ax_cnt_missIntegerRecommendedCount of missed AX probescpt_missed_xa
probe_ax_cnt_incorrIntegerRecommendedCount of inccorect responses to AX probescpt_wrong_xa
probe_ay_accFloatRecommendedaccuracy of Y probes following A cues (IE target cue followed by a non-target probe)
probe_ay_rtFloatRecommendedMedian reaction time to Y probes following A cues
probe_ay_cnt_hitIntegerRecommendedcount of correct responses to AY probes
probe_ay_cnt_missIntegerRecommendedCount of missed AY probes
probe_ay_cnt_incorrIntegerRecommendedCount of inccorect responses to AY probes
cue_b_accFloatRecommendedaccuracy of the responses to "B" cues (non-target cues)
cue_b_rtFloatRecommendedmedian reaction time for B cues
cue_b_cnt_hitIntegerRecommendedNumber of responses to B cues
cue_b_cnt_missIntegerRecommendedNumber of missed B cues
cue_b_cnt_incorrIntegerRecommendedNumber of inccorect responses to B cues
probe_bx_accFloatRecommendedaccuracy of X probes following B cues (IE non-target cue followed by target probe)
probe_bx_rtFloatRecommendedMedian reaction time to X probes following B cues
probe_bx_cnt_hitIntegerRecommendedcount of correct responses to BX probes
probe_bx_cnt_missIntegerRecommendedCount of missed BX probes
probe_bx_cnt_incorrIntegerRecommendedCount of inccorect responses to BX probes
probe_by_accFloatRecommendedaccuracy of Y probes following B cues (IE non-target cue followed by non-target probe)
probe_by_rtFloatRecommendedMedian reaction time to Y probes following B cues
probe_by_cnt_hitIntegerRecommendedcount of correct responses to BY probes
probe_by_cnt_missIntegerRecommendedCount of missed BY probes
probe_by_cnt_incorrIntegerRecommendedCount of inccorect responses to BY probes
cpt_absolute_percent_xaIntegerRecommendedAX absolute percent
cpt_relative_percent_xaFloatRecommendedAX relative percent
visitString50RecommendedVisit nameCharacter description of each type of visitassessment_number
version_formString100RecommendedForm used/assessment name
nc_dpFloatRecommendedCPT d Prime Scoredprime
completedIntegerRecommendedChecks if completed0::30=No; 1=Yes; 2=Yes, lost; 3=Unverifiedcompleted_ax_cpt
mean_rtFloatRecommendedMean RT across all trials - BEFORE FILTER
std_popFloatRecommendedStandard Deviation of RT
std_3FloatRecommended3 Standard Deviations of RT
lo_stdFloatRecommendedMean RT - 3 SDs
hi_stdFloatRecommendedMean RT + 3 SDs
ax_countIntegerRecommendedTotal AX trials completed
ay_countIntegerRecommendedTotal AY trials completed
bx_countIntegerRecommendedTotal BX trials completed
by_countIntegerRecommendedTotal BY trials completed
ax_rtFloatRecommendedAX Correct RT probe Trials
ay_rtFloatRecommendedAY Correct RT probe Trials
bx_rtFloatRecommendedBX Correct RT probe Trials
by_rtFloatRecommendedBY Correct RT probe Trials
pbsi_errorrateString10RecommendedPBSI for Errors
pbsi_rtString10RecommendedPBSI for RT
pbsi_sumString10RecommendedPBSI Errors + RT
erp_axFloatRecommendedERPs for AX trials
erp_ayFloatRecommendedERPs for AY trials
erp_bxFloatRecommendedERPs for BX trials
erp_byFloatRecommendedERPs for BY trials
a_cue_biasFloatRecommendedAX and AY signal detection bias
bx_int_rtString50RecommendedRT: BX and BY performance (behavioral interference)
bx_int_accString50RecommendedAccuracy: BX and BY performance (behavioral interference)
pb_index_rtFloatRecommendedRT: Proactive Behavioral Index
pb_index_accFloatRecommendedAccuracy: Proactive Behavioral Index
pb_index_sumFloatRecommendedSum of RT + Accuracy: Proactive Behavioral Index
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: ax_cpt01 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.