Background: The 5-visual analogue scale Richards-Campbell Sleep Questionnaire subjective sleep measure is widely used in intensive care. A cut-off score indicative of good quality sleep has not been established and is required to guide the categorisa-tion of individual patient and unit wide sleep quality.

Design and Methods: The aim was to determine the global Richards-Campbell Sleep Questionnaire cut-off score for good to very good sleep during an intensive care unit stay in non-ventilated patients. The study was a secondary (cohort) retrospective analysis of patient self-report data (n=32) from an interventional study testing a sleep promotion bundle. The Standards for Reporting Diagnostic Accuracy studies statement were used to report the study. The study was conducted in two mixed adult 12 and 20-bed ICUs of a tertiary referral hospital in a metropolitan area. In the morning, eligible patients were administered the Richards-Campbell Sleep Questionnaire together with a 5-category item Likert scale in which patients rated their nocturnal sleep quality as ‘very poor’, ‘poor’, ‘fair’, ‘good’ and ‘very good’. Receiver Operator Curve analysis was performed.

Results: Thirty-seven per cent (n=32) of the total sample of 84 adult intensive care patients were females. The median age was 61.5 (51, 72) years. Self-reported median global Richards-Campbell Sleep Questionnaire score was 54.4 (30.1, 77.1) mm. A global score of ≥63.4 mm was the optimal cut-off for self- reported ‘good sleep’ (sensitivity: 87%, specificity: 81% and area under the curve: 0.896).

Conclusions: Although the study requires replication in ventilated patients and other ICU settings, the cut-off score (63 mm) could be used to guide the categorisation of individual patient and unit wide sleep quality.