Participants
Insomnia
DISORDERS, DISORDERS
Inclusion criteria were: (1) individuals aged ≥18 years, (2) ability to communicate in English; (3) regular access to internet, smartphone, and email, and (4) score ≥10 on the Insomnia Severity Index (ISI) [Exclusion criteria were: (1) shift work (fixed night shift working between 12am-5am and rotating work schedules involving night shift) during the study period, (2) significant symptoms of the following sleep disorders based on Duke Structured Clinical Interview for Sleep Disorders (DSISD) [