| Visits | Months since baseline visit, start year, current status of participant, and year of death (if deceased) | NIH, JHU | All |
| Diagnosis | Consensus diagnosis, clinician judgment of symptoms (and symptom onset date) | NIH, JHU | All |
| Demographics and Study Status | Birth year, sex, race, Hispanic origin, education, handedness, primary language, marital status, baseline visit year, death year (if deceased) | NIH, JHU | All |
| Family History of Dementia – 1 | Family history of dementia (yes/no) | NIH | All |
| Family History of Dementia – 2 | Detailed information about family members with a history of dementia | JHU | Not yet available |
| Health History | Health history (cardiovascular, lung, thyroid, cerebrovascular, neurologic, psychiatric), cigarette smoking, substance use | NIH, JHU | All |
| Medications | Medication use | NIH, JHU | All |
| Vital Signs, Sensory Status and Anthropometry | Height, weight, BMI, blood pressure, vision, hearing, waist, hip and neck circumference | NIH, JHU | Not yet available |
| Neurologic Evaluation | UPDRS, ocular motility, strength, reflexes, neuropathy, neurologic summary | JHU | Not yet available |
| Cognitive Assessment | Neuropsychological test scores | NIH, JHU | All |
| Neuropsychiatric Symptoms | NPI-Q, GDS, HAM-D | NIH, JHU | All |
| Functional Evaluation | CDR rating, CDR-Sum of Boxes, FAQ | NIH, JHU | All |
| Physical function | Chair stands, standing balance, 4 meter walk, grip strength | JHU | All |
| Leisure activities | CHAMPS questionnaire, LAQ questionnaire | JHU | All |
| Actigraphy | Actigraphy measures of physical activity and circadian rhythm | JHU | Not yet available |
| Audiometry | Hearing history, hearing health care utilization, audiometry results | JHU | Not yet available |
