Table 1.
Sociodemographic and clinical characteristics of the study sample by data sources
| Combined legacy dataset (N = 966) |
NACC (N = 3675) |
ADNI (N = 714) |
|
|---|---|---|---|
| Age | |||
| N | 966 | 3675 | 714 |
| Mean (SD) | 72.56 (8.44) | 70.92 (9.86) | 75.34 (6.71) |
| Median [range] | 74.0 [45.00–90.00] | 71.0 [22.00–100.0] | 75.6 [55.10–90.90] |
| Missing, n (%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) |
| Sex (n, %) | |||
| Male | 566 (58.6%) | 1687 (45.9%) | 416 (58.3%) |
| Female | 400 (41.4%) | 1988 (54.1%) | 298 (41.7%) |
| Missing | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) |
| Education (years) | |||
| N | 312 | 3667 | 714 |
| Mean (SD) | 14.75 (3.09) | 15.41 (3.31) | 15.66 (2.96) |
| Median [range] | 15.0 [5.00–35.00] | 16.0 [0.00–30.00] | 16.0 [6.00–20.00] |
| Missing, n (%) | 654 (67.7%) | 8 (0.2%) | 0 (0.0%) |
| Global CDR | |||
| N | 208 | 3675 | 714 |
| Mean (SD) | 0.50 (0.00) | 0.44 (0.51) | 0.41 (0.30) |
| Median [range] | 0.5 [0.50–0.50] | 0.5 [0.00–3.00] | 0.5 [0.00–1.00] |
| Missing, n (%) | 758 (78.5%) | 0 (0.0%) | 0 (0.0%) |
| CDR-SOB | |||
| N | 966 | 3675 | 714 |
| Mean (SD) | 1.64 (0.89) | 2.17 (2.97) | 1.72 (1.76) |
| Median [range] | 1.5 [0.50–5.00] | 1.0 [0.00–18.00] | 1.5 [0.00–9.00] |
| Missing, n (%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) |
| MMSE | |||
| N | 966 | 3674 | 714 |
| Mean (SD) | 27.14 (1.93) | 26.09 (4.67) | 26.85 (2.58) |
| Median [range] | 27.0 [18.00–30.00] | 28.0 [0.00–30.00] | 27.0 [20.00–30.00] |
| Missing, n (%) | 0 (0.0%) | 1 (0.0%) | 0 (0.0%) |
| ADAS-Cog | |||
| N | 963 | – | 714 |
| Mean (SD) | 11.02 (4.54) | – | 11.43 (6.27) |
| Median [range] | 10.7 [0.83–27.67] | – | 10.7 [0.00–42.67] |
| Missing, n (%) | 3 (0.3%) | – | 0 (0.0%) |
| ADCOMS | |||
| N | 966 | 3675 | 714 |
| Mean (SD) | 0.22 (0.10) | 0.29 (0.34) | 0.25 (0.21) |
| Median [range] | 0.2 [0.03–0.58] | 0.1 [0.04–2.01] | 0.2 [0.00–1.17] |
| Missing, n (%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) |
| Clinician diagnosis of cognitive status, n (%) | |||
| Normal cognition | 0 (0.0%) | 1619 (44.1%) | 206 (28.9%) |
| Impaired-not-MCI | 0 (0.0%) | 117 (3.2%) | 0 (0.0%) |
| MCI | 966 (100.0%) | 686 (18.7%) | 349 (48.9%) |
| Dementia | 0 (0.0%) | 1253 (34.1%) | 159 (22.3%) |
| APOE | |||
| APOE ε4 carrier | 406 (42.0%) | 1419 (38.6%) | 352 (49.3%) |
| APOE ε4 non-carrier | 401 (16.5%) | 1952 (53.1%) | 362 (50.7%) |
| Missing | 159 (16.5%) | 304 (8.3%) | 0 (0.0%) |
ADCOMS Alzheimer’s Disease Composite Score, ADAS-Cog Alzheimer’s Disease Scale-Cognitive Subscale, ADNI Alzheimer’s Disease Neuroimaging Initiative, CDR-SOB Clinical Dementia Rating Scale Sum of Boxes, MCI mild cognitive impairment, MMSE Mini Mental State Examination, NACC National Alzheimer’s Coordinating Center, SD standard deviation