Light in Healthcare Environment (Ljus i sjukhusmiljö)

The aim of this study is to examine the impact of different daylight lighting conditions in the radiographer's workplace environment. Will alertness, energy levels, well-being, and sleep quality increase in the personnel at the radiology department when the lighting is differed? Which light recipe is the most beneficial for the personnel at the radiology department? Method Design: In order to ascertain the light level that yields the desired effect, an quasi-experimental study design will be employed to identify the optimal light recipe with the appropriate light intensity. A crossover design is intended for implementation. This design approach offers the advantage of having each participant serve as their own control, thereby minimizing the potential impact of inter-group differences on the results. Furthermore, it enhances statistical efficiency, even with a reduced number of study participants (Lim \& In, 2021).

Context/recruitment: Recruitments of personnel from various radiology departments at Skåne University Hospital (SUS) in Lund are planned to be conducted. A total of 18 the personnel at the radiology department will be included during the darker months of the year. At 10 to 20 workstations, a floor lamp equipped with an adjusted light prescription will be installed. Participants will be assigned to conditions in which the lamp will either be activated with the specified light recipe or remain turned off. After a duration of two weeks, the conditions will be reversed for an additional two-week period. This process will be repeated using four different light recipes to evaluate their effects on the energy levels, activity, and sleep quality of the staff. The objective is to gather insights from each season that can be implemented in the subsequent winter to determine the optimal light level.

Data collection: Subjective Measurement Methods - Staff Surveys

General Survey Participants will be asked questions regarding their typical age and gender. Additionally, a modified version of the Morningness-Eveningness Questionnaire (MEQ) will be utilized to determine each individual;s chronotype (Adan \& Almirall, 1991). A Swedish translation of this questionnaire has proven effective in assessing chronotype and is appropriate for use when a shorter assessment tool is needed (Danielsson et al., 2019).

Karolinska Sleepiness Scale (KSS) To assess the level of alertness and energy among study participants, the KSS will be utilized. This scale employs a 9-point Likert format to evaluate perceived fatigue and energy levels (Åkerstedt \& Gillberg, 1990). The KSS has been utilized in various research studies to examine the impact of lighting conditions on perceived alertness.

Patient-Reported Outcomes Information System Short Form Sleep Disturbance 8a(PROMIS) The Patient-Reported Outcomes Measurement Information System (PROMIS) is an assessment tool designed to measure self-reported sleep disturbances, including sleep quality, difficulty falling asleep, and staying asleep. It consists of 8 items rated by patients to evaluate the frequency and severity of sleep issues, supporting clinical insights into sleep-related health impacts.

Furthermore, participants \& well-being will be quantified utilizing the WHO-5 Well-Being Index.

Objective Measurement Methods: Sleep Data via Activity Bands - Actiwatch

The employment of activity monitors allows for the objective measurement of sleep. The actigraphy device is worn on the non-dominant wrist and is non-invasive (Weiss et al., 2010). It continuously tracks the participant's movements and records sleep parameters including duration and quality. These measurements can subsequently be analyzed (Ancoli-Israel et al., 2015). Due to the impracticality of wearing these wristbands during working hours, participants will attach them to their clothing at work and wear them on their wrist after work hours.

Additionally, saliva samples will be collected to measure cortisol and melatonin levels in the study participants. Cortisol secretion is stimulated by dawn light or, in winter, often by office lighting. This secretion level provides an objective parameter for assessing activation. Conversely, melatonin secretion is suppressed by the light of dawn, and the extent of this inhibition serves as an indicator of the lights effectiveness.