Table 5.
Subtest performance and frequency of low performance across CU and MCI biomarker subgroups.
| CU A−T− (n = 146) |
MCI A+T+ (n = 15) |
p-value CU A−T− and MCI A+T+ |
MCI A−T− (n = 14) |
p-value MCI A−T− and MCI A+T+ |
|
|---|---|---|---|---|---|
| OCL accuracy Mean (SD) (Transf)) | 0.987 (0.101) | 0.848 (0.082) | < 0.001a | 0.925 (0.081) | 0.017a |
| OCL accuracy Mean (SD) (Untransf, %) | 69.3 (9.3) | 56.2 (8.0) | < 0.001a | 63.6 (7.7) | 0.017a |
| OCL accuracy (z score) Mean (SD) | 0.285 (0.795) | −0.670 (0.629) | < 0.001a | −0.173 (0.634) | 0.043a |
| OCL accuracy | < 0.001b | 0.122b | |||
| Normal z > −1 | 138 (94.5%) | 9 (60.0%) | 12 (85.7%) | ||
| z ≤ −1 | 8 (5.5%) | 6 (40.0%) | 2 (14.3%) | ||
|
| |||||
| ONB accuracy Mean (SD) (Transf) | 1.369 (0.166) | 0.996 (0.237) | < 0.001a | 1.310 (0.185) | <0.001a |
| ONB accuracy Mean (SD) (Untransf, %) | 93.6 (8.2) | 68.7 (21.2) | < 0.001a | 90.6 (9.4) | 0.001a |
| ONB accuracy (z score) Mean (SD) | 0.134 (1.214) | −2.314 (1.626) | < 0.001a | −0.216 (1.284) | <0.001a |
| ONB accuracy | < 0.001b | 0.016b | |||
| Normal z > −1 | 125 (86.2%) | 4 (26.7%) | 10 (71.4%) | ||
| z ≤ −1 | 20 (13.8%) | 11 (73.3%) | 4 (28.6%) | ||
|
| |||||
| DET Mean (SD) (Transf) | 2.618 (0.135) | 2.737 (0.145) | 0.002a | 2.722 (0.147) | 0.797a |
| DET Mean (SD) (Untrans; ms) | 437.55 (162.75) | 575.326 (204.507) | 0.003a | 558.19 (208.37) | 0.825a |
| DET (z score) Mean (SD) | −0.631 (1.233) | −1.383 (1.370) | 0.027a | −1.516 (1.394) | 0.798a |
| DET | 0.056b | 0.87ba | |||
| Normal z > −1 | 95 (65.1%) | 6 (40.0%) | 6 (42.9%) | ||
| z ≤ −1 | 51 (34.9%) | 9 (60.0%) | 8 (57.1%) | ||
|
| |||||
| IDN Mean (SD) (Transf) | 2.787 (0.105) | 2.855 (0.099) | 0.017a | 2.860 (0.145) | 0.919a |
| IDN Mean (SD) (Untransf, ms) | 630.81 (164.06) | 734.555 (176.678) | 0.022a | 764.40 (276.79) | 0.730a |
| IDN (z score) Mean (SD) | −0.793 (1.226) | −1.129 (1.180) | 0.313a | −1.560 (1.850) | 0.458a |
| IDN | 0.405b | 0.096b | |||
| Normal z > −1 | 81 (55.5%) | 10 (66.7%) | 5 (35.7%) | ||
| z ≤ −1 | 65 (44.5%) | 5 (33.3%) | 9 (64.3%) | ||
|
| |||||
| Platform/Location | 0.071b | 0.292b | |||
| Home (PC) | 1 (0.7%) | 0 | 0 | ||
| PC Clinic | 38 (26.0%) | 0 | 1 (7.1%) | ||
| iPad Clinic | 107 (73.3%) | 15 (100%) | 13 (92.9%) | ||
a
p-values represent linear model ANOVAs for mean comparisons.
b
p-values represent Pearson’s Chi-squared test for frequency comparisons.
Note. CU = cognitively unimpaired; A = amyloid; T = tau; MCI = mild cognitive impairment; OCL = One Card Learning; ONB = One Back; DET = Detection; IDN = Identification; transf = transformed; untransf = untransformed (raw value), % = percentage correct (ONB, OCL), ms = milliseconds.