The RADC's variables are organized by research domain categories. Browse the listing below for more information on those categories, or find descriptions for specific variables through the index or search functions. Example data dictionaries that document the collection forms of requested datasets are also available.

Combine using:
All categories and variables:
Include study cohorts:

Currently filtering using: All categories and variables


Actigraphy Activity measured with portable actigraph
Affect and Personality Emotional affect and personality measures
ApoE and TOMM40 ApoE and TOMM40 genetic variants
Blood Measures Measures derived from blood samples
Brain Proteins Measures of brain proteins
Clinical Diagnosis Clinical diagnoses including dementia, Alzheimer's dementia, and mild cognitive impairment
Cognition Cognitive function
Cultural Experiences Measures related to cultural experiences
Decision Making and Behavioral Economics Measures of decision making, neuroeconomics, and behavioral economics
Demographics Basic demographic information including age, sex, race and education
Depression Depressive symptomatology
Digital Pen Device Digital capture of behavior
Disabilities Measures of disability
Female Reproductive History Measures of female reproductive history
Frailty Measures of frailty
Lifestyle Measures of lifestyle, behavior, and activity
Medical Conditions Chronic medical conditions and risk factors
Medicare Claims Research Identifiable Files requested from CMS
Medications Participants' current prescription medications, vitamins, supplements, and over-the-counter remedies and medicines documented at interview
Metabolism Measures of metabolism
Metabolomics Metabolomics data
Motor and Gait Measures of motor function and gait from performance-based tests and devices
Neck, Low Back and Joint Pain Measures of neck, low back and joint pain
Neuroimaging In vivo magnetic resonance imaging
Nutrition Measures of nutrition
Olfaction Measures of ability to smell
Pathology Post-mortem neuropathologic evaluation
Pulmonary Function Measures of pulmonary function
Sleep and Circadian Rhythms Measures of sleep and circadian rhythms
SES and Cognitive Resources Measures of socioeconomic status and cognitive resources
Vision Measures of vision
Well-being Measures of well-being


The variable index page provides a listing of all available variables in one table, organized by category.

Category and Variable Text Search

Search documentation for phrase.

Standard Dataset Variables

View Standard Dataset Variables

Data Dictionaries

Data dictionaries are documents describing data collection forms used to conduct participant interviews, cognitive testing, clinical evaluations, and diagnoses. Several examples of these data dictionaries are available for review.

NACC UDS Compatible Data

Some of the data collected in RADC cohort studies are directly compatible with data collected by other ADC's on NACC Uniform Data Set (UDS) forms. The compatible variables have been documented and prepared as standard datasets for distribution through data requests.