Table 1.
Characteristics of the data sets used for development and validation
| Characteristic | ADNI |
AIBL |
MCSA |
||||||
|---|---|---|---|---|---|---|---|---|---|
| Feature selection and probability development |
Feature selection and semi-independent validation |
Validation |
|||||||
| Aβ+ | Aβ− | Total | Aβ+ | Aβ− | Total | Aβ+ | Aβ− | Total | |
| Participants, n | 311 | 307 | 618 | 152 | 108 | 260 | 352 | 359 | 711 |
| SCD, n (%) | 49 (15.7) | 95 (30.9) | 144 (23.3) | 35 (23.0) | 46 (42.6) | 81 (31.1) | 204 (57.9) | 286 (79.7) | 490 (68.9) |
| MCI, n (%) | 262 (84.2) | 212 (69.1) | 474 (76.7) | 117 (77.0) | 62 (57.4) | 179 (68.9) | 148 (42.1) | 73 (20.3) | 221 (31.1) |
| Female, n (%) | 147 (47.3) | 143 (46.6) | 290 (46.9) | 63 (41.4) | 44 (40.7) | 107 (41.2) | 156 (44.3) | 141 (39.3) | 297 (41.8) |
| Mean age, y (SD) | 72.9 (6.9) | 70.1 (7.2) | 71.6 (7.2) | 76.0 (6.5) | 72.5 (7.5) | 74.5 (7.1) | 79.6 (7.9) | 70.6 (10.4) | 75.1 (10.3) |
| Higher education, n (%)∗ | 201 (64.6) | 216 (70.4) | 417 (67.5) | 44 (28.9) | 35 (32.4) | 79 (30.4) | 132 (37.5) | 138 (38.4) | 270 (38.0) |
| APOE ε4 status, n (%) | |||||||||
| Noncarrier | 113 (36.3) | 234 (76.5) | 347 (56.1) | 62 (40.8) | 89 (82.4) | 151 (58.1) | 181 (51.4) | 285 (79.4) | 466 (65.5) |
| Carrier, heterozygous | 154 (49.5) | 64 (20.9) | 218 (35.3) | 61 (40.1) | 13 (12.0) | 74 (28.5) | 146 (41.5) | 64 (17.8) | 210 (28.3) |
| Carrier, homozygous | 43 (13.8) | 8 (2.6) | 51 (8.3) | 15 (9.9) | 0 | 15 (5.8) | 18 (5.1) | 1 (0.3) | 19 (2.7) |
| Missing APOE ε4 data | 1 (0.3) | 1 (0.3) | 2 (0.3) | 14 (9.2) | 6 (5.6) | 20 (7.7) | 7 (2.0) | 9 (2.5) | 16 (2.3) |
Abbreviations: Aβ, amyloid β; ADNI, Alzheimer's Disease Neuroimaging Initiative; AIBL, Australian Imaging, Biomarker and Lifestyle Flagship Study of Ageing; APOE, apolipoprotein E; MCSA, Mayo Clinic Study of Aging; SCD, subjective cognitive decline; MCI, mild cognitive impairment.
∗
Higher education was defined as years of education ≥16 in ADNI and MCSA and ≥15 in AIBL.