Endpoint

Insomnia Severity Index (ISI) total score

CAT:outcome/insomnia-severity-index-total-scorereported in points

How it is measured

Total score on the Insomnia Severity Index, a 7-item self-report questionnaire rating the severity of sleep-onset, sleep-maintenance and early-waking problems, satisfaction, interference, noticeability and distress over the past two weeks, each item scored 0 to 4, total 0 to 28. Higher is more severe insomnia.