Table 2.
Frequency of clock error types in subjects with ≥5 years of education (n = 364)
| NO DEMENTIA* (N = 138) | WITH DEMENTIA (N = 226) | RATIO (WD/ND) | X2 | P VALUE | |
|---|---|---|---|---|---|
| Discriminating errors | |||||
| Time incorrect | 9 | 55 | 6.11 | 75.4 | 0.001 |
| No hands | 2 | 30 | 15 | 42.5 | 0.001 |
| Missing numbers | 4 | 30 | 7.5 | 34.2 | 0.001 |
| Repeated numbers | 1 | 16 | 16 | 22.4 | 0.001 |
| Substitution | 2 | 18 | 9 | 19.8 | 0.001 |
| Number orientation | 1 | 13 | 13 | 16.6 | 0.001 |
| Number order | 0 | 9 | NA | 12.9 | 0.001 |
| Numbers outside circle | 3 | 13 | 4.33 | 10.9 | 0.001 |
| Clock-like figure | 0 | 7 | NA | 10.2 | 0.001 |
| Number spacing (major) | 6 | 17 | 2.83 | 9.4 | 0.003 |
| Refusal to do | 0 | 5 | NA | 7.6 | 0.01 |
| Non-discriminating errors | |||||
| Shape incorrect | 1 | 7 | 7 | 5.98 | NS |
| Extra marks | 11 | 21 | 1.91 | 5.6 | NS |
| Number perseveration | 1 | 6 | 6 | 5 | NS |
| Hands in center | 38 | 29 | 0.76 | 2.8 | NS |
| Number of hands | 7 | 11 | 1.57 | 1.74 | NS |
| Hand length | 44 | 36 | 0.82 | 1.4 | NS |
| Number rotation | 17 | 13 | 0.76 | 1.03 | NS |
| Face geometry | 53 | 57 | 1.08 | 0.28 | NS |
| Number distance | 51 | 50 | 0.98 | 0.12 | NS |
| Number spacing (all) | 44 | 45 | 1.02 | 0.10 | NS |
| Second try | 21 | 22 | 1.09 | 0.06 | NS |
| Military time | 0 | 0 | N/A | N/A | NS |
| Anchoring | 0 | 1 | 1 | N/A | NS |
*
Subjects with subsyndromal cognitive impairment were excluded.