Table 1

Simple mediation analyses of the relationships between acupuncture/waitlist, changes in dysfunctional cognition from baseline to post-treatment and Insomnia Severity Index score at the 4-week follow-up

Mediator (M)Effect of IV on M (a)Effect of M on DV (b)Total effect (c)Direct effect (c’)Indirect effect (ab) †
Consequences−2.560.14**−4.07***−3.72***−0.35 [−1.01 to 0.04]
Worry/helplessness−3.17 0.14***−4.09***−3.64***−0.45* [−1.31 to −0.02]
Sleep expectations0.210.06−4.07***−4.08***0.01 [−0.14 to 0.35]
Medication−0.690.15*−4.15***−4.04***−0.11 [−0.69 to 0.17]
  • Baseline Insomnia Severity Index score, gender, age and education level are included as covariates.

  • Acupuncture (1=treatment, 0=control) and gender (1=male, 0=female) are dummy coded.

  • *p<0.05; **p<0.01; ***p<0.001.

  • †Bias-corrected 95% confidence intervals with 1000 bootstrap resamples are generated to test the significance of the conditional indirect effects and indices of moderation.

  • DV, dependent variable; IV, independent variable.