Fig. 4

Time (weeks) to a first response and b first response sustained for at least 3 consecutive weeks. Kaplan–Meier curves showing a time-to-first response and b time-to-first sustained response for at least consecutive 3 weeks. A patient was defined as a ‘responder’ if decrease from baseline in IDSIQ total score at a given timepoint was ≥ 20–points. IDSIQ, Insomnia Daytime Symptoms and Impacts Questionnaire