The effect of modified night lighting on sleep characteristics, and activity levels among admitted inpatients.

In this study, we intend to observe the patient-level effects of a night lighting intervention being implemented as part of a separate study, a stepped wedge cluster randomised controlled trial across six wards at the Royal Brisbane and Women's Hospital (RBWH) - ANZ trial registration ID: ACTRN12614000615684. The cluster RCT examines the effect of the intervention on ward level inpatient fall rates. The observational study described here will additionally examine the effect of the modified environment on other patient level effects, specifically sleep and activity levels. Here, we will recruit one patient per ward per month across the 14 month period of the cluster RCT (84 patients in total to be recruited). It is anticipated that across the 14 month trial period, 42 patients will be exposed to the modified environment. At the initial interview (baseline) we will ask participants to rate their visual impairment, hearing impairment, pre-admission sleepiness and sleep behaviour, current levels of sleepiness, sleep behaviour and insomnia, causes of current sleep disruption and current functional status. After the initial interview, we will follow-up participants on day three, seven and twelve (+/- one day) unless discharged from hospital or transferred out of the room earlier,. We will ask patients to rate current levels of sleepiness, sleep behaviour and insomnia, current functional status, and causes of sleep disruption over preceding days. We will also ask participants to rate their satisfaction with the physical environment and suggestions for improvements in the physical environment to support patient sleep and mobility. In addition to the above measures, we will collect continuous data on patient activity levels and light exposure through the use of a wrist worn actigraph (maximum of 12 days from initial interview). Over the same period, we will collect continuous data on environmental light variation in the room and bathroom through the use of a wall-mounted light sensing data logger. Opening and closing of the toilet door will be collected using a simple state change data logger.