Data structure | Type of test | Power (%) | ||
---|---|---|---|---|
a | GPD | Normally distributed | One-way ANOVA | 6 |
b | GPN | Normally distributed | One-way ANOVA | 20 |
c | TMT | Normally distributed | One-way ANOVA | 8 |
d | GPD RM time | Normally distributed | RM ANOVA | 100 |
e | GPD*group | Normally distributed | RM ANOVA | 9 |
f | GPN RM time | Normally distributed | RM ANOVA | 100 |
g | GPN*group | Normally distributed | RM ANOVA | 13 |
h | TMT RM time | Normally distributed | RM ANOVA | 100 |
i | TMT*group | Normally distributed | RM ANOVA | 9 |
j | Δ GPD | Normally distributed | One-way ANOVA | 9 |
k | Δ GPN | Normally distributed | One-way ANOVA | 13 |
l | Δ TMT | Normally distributed | One-way ANOVA | 15 |
m | Δ GPD (sham and control) | Normally distributed | One-way ANOVA | 81 |
n | Δ GPN (sham and control) | Normally distributed | One-way ANOVA | 99 |
o | Δ TMT (sham and control) | Normally distributed | One-way ANOVA | 12 |
p | Corr all | Non-normally distributed | Partial Pearson correlation, two-tailed | 65 |
q | Corr active | Non-normally distributed | Partial Pearson correlation, two-tailed | 25 |
r | Regression all | Non-normally distributed* | Linear multiple regression | 97 |
s | Regression active | Non-normally distributed* | Linear multiple regression | 41 |
Lines refer to the alphabetical value provided in the Results section. Post hoc power calculations were performed on the sampled data in G*Power for Windows. For one-way and RM ANOVA, the n and SDs from the data with desired alpha level of 0.05 were used. For the correlation analysis, a hypothetical regression value of 0.03 against a zero correlation were used. For regression analysis, the observed R2 values were used. Deviations from normal distribution in the sample containing all participants were significantly non-normal: head circumference, D(60) = 0.15, p < 0.01; age, D(60) = 0.22, p < 0.01; doses of nicotine in last 2 h before undergoing stimulation, D(60) = 0.33, p < 0.01; doses of caffeine in last 2 h before undergoing stimulation, D(60) = 0.29, p < 0.01; hours awake, D(60) = . , p = 0.02; and hours of sleep, D(60) = 0.15, p < 0.01. Deviations from normal distribution in the sample containing participants from the active group were significantly non-normal: age, D(20) = 0.21, p = 0.02; doses of nicotine in last 2 h before undergoing stimulation, D(20) = 0.40, p < 0.01; doses of caffeine, D(20) = 0.32, p < 0.10; and hours of sleep, D(20) = 0.21, p = 0.02.
*The assumptions for regression regarding homoscedasticity, independent errors and normally distributed errors were met.