Table 2.
Neuropsychology Test Scores and Missing Data
| Domain | Test | Posterior cortical atrophy | Alzheimer disease | |||
| Mean (SD) [min–max] | Missing data % | Mean (SD) [min–max] | Missing data % | p Value | ||
| Visuoperceptual | Usual views | 63.5 (30.8) [0.0–100.0] | 22.6 | 91.8 (10.4) [65.0–100.0] | 13.8 | <0.001a |
| Unusual views | 21.7 (23.6) [0.0–95.0] | 22.6 | 55.4 (25.5) [5.0–95.0] | 13.8 | <0.001 | |
| VOSP object decision | 54.3 (22.1) [25.0–100.0] | 0.0 | 81.6 (11.8) [55.0–100.0] | 1.7 | <0.001a | |
| VOSP fragmented letters | 26.3 (27.8) [0.0–100.0] | 11.8 | 71.1 (30.6) [0.0–100.0] | 3.4 | <0.001 | |
| Early visual | CORVIST hue discrimination | 69.1 (32.7) [0.0–100.0] | 8.6 | 81.8 (25.2) [0.0–100.0] | 5.2 | 0.011a |
| Crowding (time) | 80.2 (21.7) [0.0–95.3] | 26.9 | 85.1 (13.4) [0.0–93.0] | 10.3 | 0.127a | |
| VOSP figure/ground | 81.3 (15.2) [50.0–100.0] | 4.3 | 91.8 (8.2) [70.0–100.0] | 3.4 | <0.001a | |
| Efron shape discrimination | 74.2 (17.1) [50.0–100.0] | 4.3 | 88.6 (15.3) [50.0–100.0] | 5.2 | <0.001 | |
| Episodic memory | Recognition (words) | 74.4 (16.8) [48.0–100.0] | 29.0 | 74.9 (18.8) [48.0–100.0] | 36.2 | 0.891 |
| Recognition (faces) | 81.9 (13.1) [48.0–100.0] | 1.1 | 64.2 (13.3) [48.0–100.0] | 34.5 | <0.001 | |
| Language | Graded difficulty naming | 70.5 (27.5) [0.0–100.0] | 0.0 | 64.4 (29.6) [0.0–100.0] | 0.0 | 0.197 |
| Concrete synonyms | 82.1 (15.7) [0.0–100.0] | 11.8 | 82.7 (12.4) [48.0–100.0] | 15.5 | 0.821 | |
| Baxter spelling | 51.7 (31.9) [0.0–100.0] | 6.5 | 58.5 (29.7) [0.0–100.0] | 10.3 | 0.219 | |
| Executive/calculation | Graded difficulty arithmetic | 45.3 (18.3) [0.0–88.5] | 9.7 | 54.0 (19.3) [0.0–88.5] | 44.8 | 0.027 |
| Digit span (forwards) | 55.5 (21.3) [8.3–100.0] | 23.7 | 52.7 (17.4) [16.7–100.0] | 3.4 | 0.411 | |
| Digit span (backwards) | 28.3 (14.9) [0.0–100.0] | 24.7 | 33.0 (19.9) [0.0–100.0] | 1.7 | 0.130a | |
| Cognitive estimates | 35.2 (22.4) [0.0–90.0] | 4.3 | 34.8 (20.8) [0.0–90.0] | 3.4 | 0.910 | |
| Visuospatial | Cancellation (N correct) | 76.8 (25.7) [0.0–100.0] | 3.2 | 95.6 (7.4) [68.4–100.0] | 5.2 | <0.001a |
| Cancellation (time) | 63.9 (13.9) [0.0–89.3] | 5.4 | 52.1 (22.8) [0.0–82.2] | 5.2 | 0.001a | |
| VOSP number location | 30.4 (30.3) [0.0–100.0] | 4.3 | 53.5 (40.2) [0.0–100.0] | 5.2 | <0.001a | |
| VOSP dot count (N correct) | 49.2 (33.3) [0.0–100.0] | 2.2 | 82.9 (26.3) [0.0–100.0] | 5.2 | <0.001a | |
| VOSP dot count (time) | 74.7 (16.0) [0.0–95.7] | 49.5 | 72.2 (18.6) [0.0–88.7] | 36.2 | 0.523 | |
Abbreviations: CORVIST = Cortical Vision Screening Test; N correct = number of items correct; VOSP = Visual Object and Space Perception.
Neuropsychology test scores are shown as percentage of maximum score per group (higher percentage corresponds to less impairment, less errors, faster time to complete). Missing data are shown as percentage missing per group. Significant differences between diagnostic groups on each test assessed through independent t tests.
a
Mann-Whitney U statistic reported because of heterogeneity of variance.