Table 1.

Statistical table

Data structureType of testPower (95% C.I.)
Memory accuracy (beta distribution)
• Double vs singleMixed-model ANOVA, Bonferroni’s testCI: 1.712, 10.260
• Sham vs singleCI: −2.924, 5.765
• Double vs shamCI: 0.221, 8.910
Mathematical accuracy (beta distribution)

  • Double vs single

Mixed-model ANOVA, Bonferroni’s testCI: −2.316, 1.836

  • Sham vs single

CI: −3.674, 0.547

  • Double vs sham

CI: −0.787, 3.434
Time of memorizing and calculation (gamma distribution)

  • Double vs single

Mixed-model ANOVA, Bonferroni’s testCI: −1.468, −0.544

  • Sham vs single

CI: −0.338, 0.586

  • Double vs sham

CI: −1.336, −0.428
Recall response time (gamma distribution)

  • Double vs single

Mixed-model ANOVA, Bonferroni’s testCI: −0.960, 1.710

  • Sham vs single

CI: 0.877, 3.591

  • Double vs sham

CI: −0.502, 3.216

  • C.I. indicates confidence interval. Detailed information about assumption testing of mixed-model ANOVA are presented in Extended Data Table 1-1.