Participants
psychiatric disorders
CHRONIC INSOMNIA
A total of 211 adults with chronic insomnia were recruited from the community through media advertisements and physician referrals. All participants included in the study met the following criteria: (1) aged 21 years or older, (2) persistent (>1 month) difficulties initiating or maintaining sleep despite adequate opportunity for sleep, (3) sleep onset latency or wake time after sleep onset of 30 minutes or more for 3 or more nights per week during 2 weeks of sleep diary monitoring, (4) ISI total score more than 10, (5) score of 2 or more on either the interference or distress item of the screening ISI. Participants were excluded if they had untreated psychiatric disorders or uncontrolled medical conditions or had conditions that interfered with sleep quality and sleep continuity. Additional details about exclusion criteria can be found in a previous publication.