Introduction
sleep disorders, fatigue, anxiety, CAU.dCBT-I, daytime sleepiness, depressive, insomnia, Insomnia
SECONDARY, DISORDERS
Insomnia is one of the most frequent sleep disorders and one of the most prevalent mental disorders in Europe, affecting approximately 6%–10% of the adult population [In October 2020, digital therapy was introduced to the German healthcare system in the form of so-called digital health applications (German: “digitale Gesundheitsanwendungen,” DiGA) and can since be prescribed by practitioners and psychotherapists to people affected, with costs being covered by the statutory health insurance system. With regard to insomnia, little is known about the feasibility and effects of dCBT-I in pragmatic study settings in Germany. However, emerging evidence from real-world studies and large-scale RCTs across different countries demonstrates promising results in the short [In this study, we compared dCBT-I as an add-on to care as usual (CAU) to a waitlist control group (WLC + CAU) while limiting exclusion criteria to an absolute minimum. With the unique situation of digital care in Germany in mind, the following primary and secondary clinical hypotheses were tested:dCBT-I + CAU reduces self-reported insomnia severity relative to WLC + CAU.dCBT-I + CAU reduces fatigue and daytime sleepiness relative to WLC + CAU.dCBT-I + CAU reduce dysfunctional beliefs and attitudes about sleep relative to WLC + CAU.dCBT-I + CAU improves well-being and quality of life relative to WLC + CAU.dCBT-I + CAU reduces depressive and anxiety symptoms relative to WLC + CAU.dCBT-I + CAU reduces dream recall frequency relative to WLC + CAU.dCBT-I + CAU reduces nightmare frequency relative to WLC + CAU.Additionally, we investigated whether potential improvements are stable over time by comparing follow-up data at 6- and 12-months follow-up in the intervention group and conducted explorative analysis on application-reported sleep diary variables.