Table 8.
Mean within-subject difference in error rate for phonological fluency and category switching, compared to category fluency.
| Parkinson’s Disease (PD) (N = 63) | Essential Tremor (ET) (N = 53) | |||||
|---|---|---|---|---|---|---|
| Ma | 95% CI | P value | Ma | 95% CI | P value | |
| Phonological fluency | ||||||
| Total errors | 2.6 | [1.0, 4.3] | .002 | 2.5 | [0.8, 4.3] | .006 |
| Perseveration errors | 1.6 | [0.6, 2.6] | .003 | 1.1 | [−0.4, 2.5] | .14 |
| Set-loss errors | 1.0 | [−0.1, 2.2] | .08 | 1.5 | [0.2, 2.7] | .02 |
| Category switching | ||||||
| Total errors | 5.1 | [2.6, 7.7] | <.001 | 3.9 | [1.4, 6.4] | .003 |
| Perseveration errors | 1.0 | [−0.5, 2.4] | .18 | 0.3 | [−1.3, 1.8] | .74 |
| Set-loss errors | 4.1 | [2.4, 5.9] | <.001 | 3.9 | [2.2, 5.7] | <.001 |
Note. PD = Parkinson’s disease; ET = Essential Tremor; M = mean difference; CI = confidence interval.
a
M represents the mean within-patient difference in error percentage compared to category fluency. Null hypothesis of “mean difference equals zero” was investigated using paired t tests.
Signifiant levels are bolded.