Figure 1
Total Tremor Score (y-Axis) by Age (x-Axis) Across the Three Diagnostic Groups.
Essential tremor (ET), green diamonds; borderline ET, blue squares, and normals, red circles. A total tremor score ≥10 (horizontal line) separated the borderline ET cases from normals with a sensitivity of 77.8% and a specificity of 94.7% (correct classification, 84.7%). One borderline ET did not have a total tremor score and two others had identical total tremor scores and ages.
Table 1
Clinical and Demographic Characteristics of Enrollees
| Characteristic | ET (N = 160) | Borderline ET (N = 28) | Normal (N = 19) | Significance (p) |
|---|---|---|---|---|
| Age (years) | 60.0 ±18.0* | 48.0±12.5 | 49.3±17.9 | <0.0011 |
| Female gender | 82 (51.3)* | 16 (57.1) | 15 (78.9) | 0.072 |
| Education (years) | 16.3±3.7 | 16.6±2.0 | 16.5±3.5 | 0.901 |
| Tremor duration (years) | 32.8±19.3 | 17.8±12.8 | Not applicable | <0.0011 |
| Relationship | <0.0012 | |||
| Proband | 50 (31.3)* | 2 (7.1) | 0 (0.0) | |
| Child | 37 (23.1) | 18 (64.3) | 8 (42.1) | |
| Sibling | 38 (23.8) | 5 (17.9) | 5 (26.3) | |
| Other | 35 (21.9) | 3 (10.7) | 6 (31.6) | |
| “Other people tell me that I have tremor” | 126 (78.8)** | 12 (42.9)*** | 3 (15.8) | <0.0012 |
| “I sometimes have tremor that I can't control” | 154 (96.3)** | 21 (75.0)*** | 8 (42.1) | <0.0012 |
| Total tremor score | 20.1±5.2** | 11.4±2.6* | 7.3±1.8 | <0.0011 |
| Spiral axis score | 2.2±1.3 (2.0)** | 1.1 ± 1.0 (1.0)*** | 0.4 ± 0.5 (0.0) | <0.0013 |
| Any kinetic tremor score ≥1.5 | 160 (100)** | 27 (96.4)** | 10 (52.6) | <0.0012 |
| Any kinetic tremor score ≥1.5 in dominant arm | 157 (98.1)** | 25 (89.3)** | 7 (36.8) | <0.0012 |
| Spiral score ≥1.5 | 126 (78.8)** | 8 (28.6)* | 0 (0.0) | <0.0012 |
| Rest tremor | 16 (10.0) | 0 (0.0) | 0 (0.0) | 0.082 |
| Head tremor | 72 (45.0)** | 4 (14.3)*** | 0 (0.0) | <0.0012 |
| Voice tremor | 26 (16.4)*** | 1 (3.6) | 0 (0.0) | <0.0012 |
| Intention tremor | 62 (38.8)* | 1 (3.6) | 2 (10.5) | <0.0012 |