{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T22:08:50Z","timestamp":1792188530815,"version":"4.4.0"},"reference-count":5,"publisher":"Elsevier BV","issue":"1","license":[{"start":{"date-parts":[[2021,8,10]],"date-time":"2021-08-10T00:00:00Z","timestamp":1628553600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2021,8,10]],"date-time":"2021-08-10T00:00:00Z","timestamp":1628553600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/100000090","name":"Congressionally Directed Medical Research Programs","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100000090","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Military Med Res"],"published-print":{"date-parts":[[2021,12]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    Service members are at risk for sleep and psychological conditions affecting their readiness. Chronotype (\u201cmorningness\u201d or \u201ceveningness\u201d) is strongly associated with sleep, health and performance. The objective of this study was to examine associations between validated measures of chronotype and sleep quality, daytime functioning, alertness, and symptoms of depression, anxiety, and post-traumatic stress disorder (PTSD) in US service members (\n                    <jats:italic>n<\/jats:italic>\n                    \u2009=\u2009298). Although predominantly young males (who skew toward eveningness in civilian populations), these Sailors skewed toward morningness (35.6% morning, 51.3% intermediate). Eveningness was associated with symptoms of depression and post-traumatic stress disorder (PTSD) (\n                    <jats:italic>P<\/jats:italic>\n                    \u2009&lt;\u20090.01), less time in bed (\n                    <jats:italic>P<\/jats:italic>\n                    \u2009&lt;\u20090.05), more sleep disruption (\n                    <jats:italic>P<\/jats:italic>\n                    \u2009&lt;\u20090.01), and poorer daytime functioning and alertness (\n                    <jats:italic>P<\/jats:italic>\n                    \u2009&lt;\u20090.05). Evening types were less likely to consider sleep important for performance (\n                    <jats:italic>P<\/jats:italic>\n                    \u2009&lt;\u20090.05). To maximize service member readiness, schedules should be aligned with endogenous rhythms, whenever possible, and evening chronotypes may benefit from targeted interventions. Chronotype should be examined alongside health and readiness in service members.\n                  <\/jats:p>","DOI":"10.1186\/s40779-021-00335-2","type":"journal-article","created":{"date-parts":[[2021,8,10]],"date-time":"2021-08-10T05:03:38Z","timestamp":1628571818000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Chronotype and self-reported sleep, alertness, and mental health in U.S. sailors"],"prefix":"10.1016","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0482-589X","authenticated-orcid":false,"given":"Elizabeth M.","family":"Harrison","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandra P.","family":"Easterling","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emily A.","family":"Schmied","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suzanne L.","family":"Hurtado","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gena L.","family":"Glickman","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"78","published-online":{"date-parts":[[2021,8,10]]},"reference":[{"issue":"4","key":"335_CR1","doi-asserted-by":"publisher","first-page":"515","DOI":"10.1016\/j.cbpra.2017.12.007","volume":"25","author":"KE Pruiksma","year":"2018","unstructured":"Pruiksma KE, Fina B, Dietch JR, Dondanville KA, Williams J, Wright EC, et al. Special considerations in the adaptation of cognitive behavioral therapy for insomnia with active-duty U.S. Army personnel. Cogn Behav Pract. 2018;25(4):515\u201330.","journal-title":"Cogn Behav Pract"},{"issue":"6","key":"335_CR2","doi-asserted-by":"publisher","first-page":"429","DOI":"10.1016\/j.smrv.2007.07.005","volume":"11","author":"T Roenneberg","year":"2007","unstructured":"Roenneberg T, Kuehnle T, Juda M, Kantermann T, Allebrandt K, Gordijn M, et al. Epidemiology of the human circadian clock. Sleep Med Rev. 2007;11(6):429\u201338.","journal-title":"Sleep Med Rev"},{"issue":"2","key":"335_CR3","doi-asserted-by":"publisher","first-page":"94","DOI":"10.1007\/s40675-018-0113-8","volume":"4","author":"L Kivel\u00e4","year":"2018","unstructured":"Kivel\u00e4 L, Papadopoulos MR, Antypa N. Chronotype and psychiatric disorders. Curr Sleep Med Rep. 2018;4(2):94\u2013103.","journal-title":"Curr Sleep Med Rep"},{"issue":"5","key":"335_CR4","doi-asserted-by":"publisher","first-page":"504","DOI":"10.1001\/jamapsychiatry.2014.28","volume":"71","author":"RC Kessler","year":"2014","unstructured":"Kessler RC, Heeringa SG, Stein MB, Colpe LJ, Fullerton CS, Hwang I, et al. Thirty-day prevalence of DSM-IV mental disorders among nondeployed soldiers in the US Army: results from the army study to assess risk and resilience in servicemembers (Army STARRS). JAMA Psychiat. 2014;71(5):504\u201313.","journal-title":"JAMA Psychiat"},{"issue":"3","key":"335_CR5","doi-asserted-by":"publisher","first-page":"241","DOI":"10.1016\/0191-8869(91)90110-W","volume":"12","author":"A Adan","year":"1991","unstructured":"Adan A, Almirall H. Horne & \u00d6stberg morningness-eveningness questionnaire: a reduced scale. Pers Individ Differ. 1991;12(3):241\u201353.","journal-title":"Pers Individ Differ"}],"container-title":["Military Medical Research"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1186\/s40779-021-00335-2.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1186\/s40779-021-00335-2\/fulltext.html","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1186\/s40779-021-00335-2.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T20:52:30Z","timestamp":1772830350000},"score":1,"resource":{"primary":{"URL":"https:\/\/mmrjournal.biomedcentral.com\/articles\/10.1186\/s40779-021-00335-2"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,8,10]]},"references-count":5,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2021,12]]}},"alternative-id":["335"],"URL":"https:\/\/doi.org\/10.1186\/s40779-021-00335-2","relation":{},"ISSN":["2054-9369"],"issn-type":[{"value":"2054-9369","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,8,10]]},"assertion":[{"value":"25 January 2021","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"29 July 2021","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"10 August 2021","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Ethics approval and consent to participate are noted in the manuscript above. The study protocol was approved by the Naval Health Research Center Institutional Review Board in compliance with all applicable federal regulations governing the protection of human subjects. Research data were derived from an approved Naval Health Research Center study, Institutional Review Board Protocol Number NHRC.2017.0010.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"EMH, APE, EAS, SLH, and GLG have no conflicts of interest to disclose. SLH and GLG are employees of the U.S. Government, respectively. This work was prepared as part of their official duties. The views expressed in this article are those of the authors and do not necessarily reflect the official policy or position of the Department of the Navy, Department of Defense, or U.S. Government.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"43"}}