Sleep hygiene was assessed using the modified checklist reported by Tamura and Tanaka [35].

・Being bathed in sunlight after getting up
・Eating breakfast every morning
・Not taking a nap after 15:00
・Not going out to bright places after 21:00
・Avoiding the use of electronic devices just before bed time
・Not drinking alcohol to induce sleep
・Not thinking about troubles in bed
・Keeping the bedroom quiet and comfortable
・Using a comfortable mattress and bedclothing
・Preventing an irregular getting up time (within 2 h)