Figure 2.

Comparison of effects of ACH administration duration on sleep efficiency. (a) Sleep diary showed constant improvement in sleep efficiency for ACH phase group compared with gradual deterioration for placebo group. Group difference in sleep efficiency over time became significant when ACH was administered for four weeks (p < 0.001, q < 0.001 for 0–4 weeks), which did not reach statistical significance after two weeks of use (p = 0.067 for 0–2 weeks). (b) Actigraphy revealed that sleep efficiency did not show clear differences between ACH and placebo phases; however, the significant improvement effect was only obvious after continuous use of ACH for four weeks (p = 0.066 for 0–2 weeks vs. p = 0.007, q = 0.016 for 0–4 weeks). * q-value < 0.05 and ** q-value < 0.01, pFDR was calculated for group × time difference by linear mixed-effects model to account for multiple testing.