Light is a fundamental part of our daily lives, shaping human perception of the world and vision and playing a crucial role in numerous aspects of well-being and the environment. This is influenced by various factors, including circadian rhythms, which means the best activity times, age, and sport-related characteristics.
Numerous research groups in various fields and laboratory studies investigate the phenomena in light research and light therapy. Unfortunately, there is still a lack of international consensus regarding the degree of standardization, making it difficult to compare the various studies. This leads to a kind of "butterfly collection" in the scientific debate on light and its effects on humans.
Prof. Dr. Manuel Spitschan, Head of the Assistant Professorship of Chronobiology & Health, has developed a checklist as the responsible leader of a research group within the NETIAS (Network of European Institutes for Advanced Study) on how (clinical) studies should deal with light stimuli. The study was published under the title: "ENLIGHT Consensus Checklist and Guidelines for reporting laboratory studies on the non-visual effects of light in humans" in the journal "eBioMedicine" as an open access document. The journal has an impact factor of 11.1.
"The checklist, which we developed with international experts, is intended to make study results more comparable in the long term. If I know which light, intensity, or brightness was used in the studies, then it makes the research more robust and reproducible," says Prof Spitschan, explaining the approach.
A six-stage consensus process, including expert interviews and focus groups, resulted in a checklist with 25 items, nine of which are categorized as essential. The items include basic information on the conduct of the study. This includes details about the setting (e.g., whether the study took place in a room or laboratory), the type of light source used, and how the light was used. However, the timing of experiments, the illuminance, and its effects on the human circadian system also play a role. Information on the light source, including the type (LEDs, fluorescent lights, monitor), provides a clear guide for future replications of a study. The NETIAS research group "Light and Human Health" which includes Prof Spitschan, Dr. Raymond Najjar (National University of Singapore, Singapore), Dr. Elise McGlashan (Monash University, Australia), Dr. Laura Kervezee (Leiden University Medical Center, Netherlands) and Dr. Renske Lok (Stanford University, USA), acted as the steering committee for the work.
Various scientists from the fields of chronobiology, psychology, neuroscience, lighting technology, and clinical medicine contributed their expertise. The different items were discussed regarding potential problems and opportunities for improvement: "This is the first consensus checklist to comprehensively describe lighting interventions for scientific studies. We must work transparently and robustly to make evidence-based decisions. For example, if I want to make a lighting recommendation for the workplace, it is essential to have a precise vocabulary and clear language to describe this effectively. Using the checklist ensures precisely this: creating such precise language," adds the neuroscientist.
The use of the checklist is not limited to laboratory studies. In the future, it could be extended to other applications to support specific study questions. "This approach creates a solid basis for further developing and deepening our understanding of light and its diverse biomedical effects on humans," says Prof. Spitschan.
To the publication "ENLIGHT Consensus Checklist and Guidelines for reporting laboratory studies on the non-visual effects of light in humans"
To the homepage of the ENLIGHT project
To the homepage of the Rudolf Mößbauer Assistant Professorship of Chronobiology & Health
To the homepage of the joint TUM/MPI group
To the homepage of the NETIAS research group "Light and human health"
Prof. Dr. Manuel Spitschan
Rudolf Mößbauer Assistant Professorship of Chronobiology & Health
phone: 089 289 24544
Text: Bastian Daneyko