Description of the NACC database
The NACC database is made up of three main research data sets:
From 2005 to the present, ADCs have been contributing data to the Uniform Data Set (UDS), using a prospective, standardized, and longitudinal clinical evaluation of the subjects in the National Institute on Aging's ADC Program.
In 2012, a new module was added to the UDS to collect detailed clinical information related to frontotemporal lobar degeneration (FTLD). The FTLD Module is voluntarily completed by ADCs.
Beginning in 1984 and ending with the 2005 implementation of the UDS, brief, single-record descriptions of ADC subjects were collected retrospectively to form the Minimum Data Set (MDS).*
The Neuropathology Data Set (NP) contains autopsy data for a subset of both MDS and UDS subjects. Please note that changes in diagnostic criteria and staining methods may limit the available data for certain analyses.
Data collection activities are ongoing for the UDS, FTLD Module, and NP Data Sets. Please refer to the table below for more detailed information.
*Because of the lack of detailed, longitudinal, and standardized clinical data in the MDS, the utility of the MDS for research is limited, and combining the clinical data in the MDS with the UDS is generally not recommended.
More information about NACC data:
- About the NACC database
- Demographics, diagnoses, and follow-up summary tables
- The UDS study population
- The UDS data collection protocol
Table: An overview of the NACC database
|Uniform Data Set (UDS) (LONGITUDINAL)||Neuropathology Data Set (NP)||Minimum Data Set (MDS)|
|UDS||FTLD Module||Data with associated UDS visit(s)||Data with no associated UDS visit (MDS only)|
|Years covered||Sep 2005 – present||Feb 2012 – present||2005 – present||1984 – 2005||1984 – 2005|
|Study subjects||Enrollees followed at ADCs
(with or without dementia)
who died and underwent autopsy
|MDS-only subjects who died and underwent autopsy||Enrollees followed at ADCs (with or without dementia)|
|Approx # of subjects**||34,748||1,354||4,425||11,041||74,397|
|Approx # of variables||725||379||85||67|
of data collection
|Collected prospectively by clinicians, neuro-psychologists, and other ADC research personnel, using up to 18 standardized forms at each visit. Some forms also have Spanish-language and telephone versions.||Collected prospectively by clinicians, neuro-psychologists, and other ADC research personnel, using up to 13 standardized forms at each FTLD Module visit.||Standardized neuropathology form, completed by neuropathologist||Mainly abstracted retroactively from ADC medical records|
|Time period covered for each subject||Initial visit and each annual follow-up visit, plus milestones such as death or dropout||Initial FTLD Module visit and annual follow-up visit||Status of brain at autopsy||Mainly status on last ADC visit; some variables also capture initial-visit status|
|Topics covered (brief list)||
|Publications describing data set||Beekly 2004||Beekly 2004|
data forms, guidebooks, and DEDs
|UDS data forms, guidebooks, and data element dictionaries||FTLD data forms, guidebooks, and data element dictionaries||NP data form, guidebook, and
data element dictionary
data form, guidebook, and data element dictionary
**as of the December 1, 2016 data freeze