{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T04:23:02Z","timestamp":1772252582577,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2024,2,26]],"date-time":"2024-02-26T00:00:00Z","timestamp":1708905600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100004440","name":"Wellcome Trust","doi-asserted-by":"publisher","award":["204686\/Z\/16\/C"],"award-info":[{"award-number":["204686\/Z\/16\/C"]}],"id":[{"id":"10.13039\/100004440","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100004440","name":"Wellcome Trust","doi-asserted-by":"publisher","award":["204686\/Z\/16\/Z"],"award-info":[{"award-number":["204686\/Z\/16\/Z"]}],"id":[{"id":"10.13039\/100004440","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Clocks &amp; Sleep"],"abstract":"<jats:p>In humans, the nocturnal secretion of melatonin by the pineal gland is suppressed by ocular exposure to light. In the laboratory, melatonin suppression is a biomarker for this neuroendocrine pathway. Recent work has found that individuals differ substantially in their melatonin-suppressive response to light, with the most sensitive individuals being up to 60 times more sensitive than the least sensitive individuals. Planning experiments with melatonin suppression as an outcome needs to incorporate these individual differences, particularly in common resource-limited scenarios where running within-subjects studies at multiple light levels is costly and resource-intensive and may not be feasible with respect to participant compliance. Here, we present a novel framework for virtual laboratory melatonin suppression experiments, incorporating a Bayesian statistical model. We provide a Shiny web app for power analyses that allows users to modify various experimental parameters (sample size, individual-level heterogeneity, statistical significance threshold, light levels), and simulate a systematic shift in sensitivity (e.g., due to a pharmacological or other intervention). Our framework helps experimenters to design compelling and robust studies, offering novel insights into the underlying biological variability in melatonin suppression relevant for practical applications.<\/jats:p>","DOI":"10.3390\/clockssleep6010009","type":"journal-article","created":{"date-parts":[[2024,2,26]],"date-time":"2024-02-26T11:31:21Z","timestamp":1708947081000},"page":"114-128","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Power Analysis for Human Melatonin Suppression Experiments"],"prefix":"10.3390","volume":"6","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8572-9268","authenticated-orcid":false,"given":"Manuel","family":"Spitschan","sequence":"first","affiliation":[{"name":"Department of Health and Sport Sciences, TUM School of Medicine and Health, Technical University of Munich, 80992 Munich, Germany"},{"name":"TUM Institute for Advanced Study (TUM-IAS), Technical University of Munich, 85748 Garching, Germany"},{"name":"Max Planck Research Group Translational Sensory and Circadian Neuroscience, Max Planck Institute for Biological Cybernetics, 72076 T\u00fcbingen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3990-1047","authenticated-orcid":false,"given":"Parisa","family":"Vidafar","sequence":"additional","affiliation":[{"name":"Faculty of Medicine and Health, Central Clinical School, University of Sydney, Sydney, NSW 2006, Australia"},{"name":"Turner Institute for Brain and Mental Health, School of Psychological Sciences, Monash University, Clayton, VIC 3800, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8385-1550","authenticated-orcid":false,"given":"Sean W.","family":"Cain","sequence":"additional","affiliation":[{"name":"Turner Institute for Brain and Mental Health, School of Psychological Sciences, Monash University, Clayton, VIC 3800, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1156-7056","authenticated-orcid":false,"given":"Andrew J. K.","family":"Phillips","sequence":"additional","affiliation":[{"name":"Turner Institute for Brain and Mental Health, School of Psychological Sciences, Monash University, Clayton, VIC 3800, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4274-4158","authenticated-orcid":false,"given":"Ben C.","family":"Lambert","sequence":"additional","affiliation":[{"name":"Department of Statistics, University of Oxford, Oxford OX1 3LB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1007\/s11818-019-00215-x","article-title":"Effects of light on human circadian rhythms, sleep and mood","volume":"23","author":"Blume","year":"2019","journal-title":"Somnologie"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"387","DOI":"10.1080\/15502724.2021.1872383","article-title":"A review of human physiological responses to light: Implications for the development of integrative lighting solutions","volume":"18","author":"Vetter","year":"2021","journal-title":"Leukos"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"624861","DOI":"10.3389\/fneur.2021.624861","article-title":"The lighting environment, its metrology, and non-visual responses","volume":"12","author":"Schlangen","year":"2021","journal-title":"Front. 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