{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T03:19:15Z","timestamp":1782962355585,"version":"3.54.5"},"reference-count":50,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,11,5]],"date-time":"2025-11-05T00:00:00Z","timestamp":1762300800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>This study examined the impact of a shift schedule change on firefighter sleep and health outcomes (n = 24). Firefighters from a U.S. department transitioned from a 24 h on, 48 h off (24\/48) schedule to a 48 h on, 96 h off (48\/96) schedule. Wrist actigraphy and self-reported health outcomes were assessed at three time points: baseline (24\/48), 3 months post-transition, and 6 months post-transition. Objective sleep measures included total sleep time (TST), sleep efficiency (SE), sleep onset latency (SOL), and wake after sleep onset (WASO). Self-reported health outcomes included the Insomnia Severity Index (ISI), Beck Depression Inventory\u2013II (BDI-II), Beck Anxiety Inventory (BAI), Multidimensional Assessment of Fatigue (MAF), and the Alcohol Use Disorders Identification Test (AUDIT). Linear mixed-effects models (LMMs) with random intercepts were used to evaluate changes over time, adjusting for age, years of service, and individual night-time call volume. Results showed significant improvements in TST, SE, SOL, and WASO at the 3-month follow-up, which were sustained but did not further increase at 6 months. ISI and BDI-II scores also improved, while BAI, MAF, and AUDIT remained stable. These findings suggest that the 48\/96 schedule may provide short-term improvements in sleep and psychological health for firefighters in low call-volume settings. Additional research is needed in higher-volume departments and over longer timeframes.<\/jats:p>","DOI":"10.3390\/ijerph22111678","type":"journal-article","created":{"date-parts":[[2025,11,5]],"date-time":"2025-11-05T13:19:29Z","timestamp":1762348769000},"page":"1678","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Effects of a 24\/48 to 48\/96 Shift Schedule Change on Firefighter Sleep and Health: Short-Term Improvements and Six-Month Stability"],"prefix":"10.3390","volume":"22","author":[{"given":"Joel M.","family":"Billings","sequence":"first","affiliation":[{"name":"Department of Emergency, Disaster and Global Security Studies, Embry-Riddle Aeronautical University, Daytona Beach, FL 32114, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sara A.","family":"Jahnke","sequence":"additional","affiliation":[{"name":"Center for Fire, Rescue & EMS Health Research, NDRI-USA, Leawood, KS 66224, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Duncan, D.T., Kawachi, I., and Redline, S. (2019). The Social Epidemiology of Sleep, Oxford University Press.","DOI":"10.1093\/oso\/9780190930448.001.0001"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"292","DOI":"10.1016\/j.patbio.2014.08.001","article-title":"Impacts of shift work on sleep and circadian rhythms","volume":"62","author":"Boivin","year":"2014","journal-title":"Pathol. Biol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"174","DOI":"10.1016\/j.ssci.2015.09.024","article-title":"Sound the alarm: Health and safety risks associated with alarm response for salaried and retained metropolitan firefighters","volume":"82","author":"Paterson","year":"2016","journal-title":"Saf. Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"150","DOI":"10.4103\/1463-1741.181998","article-title":"The acute physiological stress response to an emergency alarm and mobilization during the day and at night","volume":"18","author":"Hall","year":"2016","journal-title":"Noise Health"},{"key":"ref_5","first-page":"762","article-title":"Firefighters\u2019 Reaction to Alarm, an ECG and Heart Rate Study","volume":"23","author":"Kuorinka","year":"1981","journal-title":"J. Occup. Med. Off. Publ. Ind. Med. Assoc."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"580","DOI":"10.1097\/JOM.0000000000003115","article-title":"The Influence of Emergency Call Volume on Occupational Workload and Sleep Quality in Urban Firefighters","volume":"66","author":"Jelmini","year":"2024","journal-title":"J. Occup. Environ. Med."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Wahl, C.A., Marciniak, R.A., Meyer, B.B., and Ebersole, K.T. (2025). Association Between Call Volume and Perceptions of Stress and Recovery in Active-Duty Firefighters. Fire, 8.","DOI":"10.3390\/fire8070268"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1","DOI":"10.3390\/merits4010001","article-title":"Workloads of Emergency Call Types in Active-Duty Firefighters","volume":"4","author":"Marciniak","year":"2024","journal-title":"Merits"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Hunnicutt, L.E., Corgan, M., Brown, S.R., Nygaard, A., Meares, G.L., and Collier, S.R. (2024). Sleep Differences in Firefighters: Barracks vs. Home. Int. J. Environ. Res. Public Health, 21.","DOI":"10.3390\/ijerph21091155"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1002\/ajim.23194","article-title":"Interactions between home, work, and sleep among firefighters","volume":"64","author":"Watkins","year":"2020","journal-title":"Am. J. Ind. Med."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1080\/15402002.2021.2021912","article-title":"Intra-Tour Variation of Firefighter Sleep Duration and Sleep-Wake Cycle within the 24\/48 and 48\/96 Shift Schedules","volume":"21","author":"Billings","year":"2022","journal-title":"Behav. Sleep Med."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"2248","DOI":"10.1177\/1359105320909861","article-title":"Sleep disturbance and cognitive functioning among firefighters","volume":"26","author":"Stout","year":"2021","journal-title":"J. Health Psychol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1171","DOI":"10.2147\/NDT.S156501","article-title":"The impact of total sleep deprivation upon cognitive functioning in firefighters","volume":"14","author":"Kujawski","year":"2018","journal-title":"Neuropsychiatr. Dis. Treat."},{"key":"ref_14","first-page":"2662","article-title":"Examining the impact of occupational stress and shift work schedules on the cognitive functions among firefighters in normal condition","volume":"81","author":"Askari","year":"2025","journal-title":"WORK"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1016\/j.sleh.2014.12.008","article-title":"Duration, timing and quality of sleep are each vital for health, performance and safety","volume":"1","author":"Czeisler","year":"2015","journal-title":"Sleep Health J. Natl. Sleep Found."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1108\/S1479-3555(2009)0000007009","article-title":"Sleep and recovery","volume":"Volume 7","author":"Sonnentag","year":"2009","journal-title":"Current Perspectives on Job-Stress Recovery"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"294","DOI":"10.1016\/j.pcad.2008.10.003","article-title":"Cardiovascular, Inflammatory and Metabolic Consequences of Sleep Deprivation","volume":"51","author":"Mullington","year":"2009","journal-title":"Prog. Cardiovasc. Dis."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"202","DOI":"10.1097\/CRD.0b013e318215c105","article-title":"Cardiovascular Disease in US Firefighters: A Systematic Review","volume":"19","author":"Soteriades","year":"2011","journal-title":"Cardiol. Rev."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"928","DOI":"10.1097\/JOM.0b013e318225898f","article-title":"Sleep Problems, Depression, Substance Use, Social Bonding, and Quality of Life in Professional Firefighters","volume":"53","author":"Carey","year":"2011","journal-title":"J. Occup. Environ. Med."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"e150","DOI":"10.1097\/JOM.0000000000001559","article-title":"Sleep, obesity, and injury among US male career firefighters","volume":"61","author":"Kaipust","year":"2019","journal-title":"J. Occup. Environ. Med."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"233","DOI":"10.5664\/jcsm.4534","article-title":"Common sleep disorders increase risk of motor vehicle crashes and adverse health outcomes in firefighters","volume":"11","author":"Barger","year":"2015","journal-title":"J. Clin. Sleep Med."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1097\/JOM.0000000000000912","article-title":"Physiological Load and Psychological Stress During a 24-hour Work Shift Among Finnish Firefighters","volume":"59","author":"Kaikkonen","year":"2017","journal-title":"J. Occup. Environ. Med."},{"key":"ref_23","unstructured":"Elliot, D., and Kuehl, K. (2007). The Effects of Sleep Deprivation on Fire Fighters and EMS Responders. Int. Assoc. Fire Chiefs, Available online: https:\/\/www.iafc.org\/docs\/default-source\/1safehealthshs\/progssleep_sleepdeprivationreport.pdf."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/s40171-023-00366-9","article-title":"Embracing Flexibility Post-COVID-19: A Systematic Review of Flexible Working Arrangements Using the SCM-TBFO Framework","volume":"25","author":"Vohra","year":"2024","journal-title":"Glob. J. Flex. Syst. Manag."},{"key":"ref_25","unstructured":"Brynjolfsson, E., Horton, J.J., Ozimek, A., Rock, D., Sharma, G., and TuYe, H.-Y. (2020). COVID-19 and Remote Work: An Early Look at US Data, National Bureau of Economic Research."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"299","DOI":"10.5271\/sjweh.3307","article-title":"Systematic review on the association between employee worktime control and work-non-work balance, health and well-being, and job-related outcomes","volume":"38","author":"Nijp","year":"2012","journal-title":"Scand. J. Work. Environ. Health"},{"key":"ref_27","unstructured":"Koen, S. (2005). 24\/48 VS. 48\/96 Work Schedules: A Comparative Analysis, Round-The-Clock Systmes."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"294","DOI":"10.1097\/JOM.0000000000000624","article-title":"Firefighter Shift Schedules Affect Sleep Quality","volume":"58","author":"Billings","year":"2016","journal-title":"J. Occup. Environ. Med."},{"key":"ref_29","first-page":"53","article-title":"Does 24-48 or 48-96 Promote Better REM Sleep Within Firefighters?","volume":"2","author":"Balderrama","year":"2024","journal-title":"Int. J. Exerc. Sci. Conf. Proc."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"25","DOI":"10.22514\/SV101.042015.3","article-title":"The impact of changing work schedules on American firefighters\u2019 sleep patterns and well-being","volume":"10","author":"Caputo","year":"2015","journal-title":"Signa Vitae J. Intesive Care Emerg. Med."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1093\/sleep\/26.1.81","article-title":"Further Validation of Actigraphy for Sleep Studies","volume":"26","author":"Pires","year":"2003","journal-title":"Sleep"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"389","DOI":"10.1016\/S1389-9457(00)00098-8","article-title":"Comparison of actigraphic, polysomnographic, and subjective assessment of sleep parameters in sleep-disordered patients","volume":"2","author":"Kushida","year":"2001","journal-title":"Sleep Med."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"S4","DOI":"10.1080\/15402002.2015.1046356","article-title":"The SBSM Guide to Actigraphy Monitoring: Clinical and Research Applications","volume":"13","author":"Martin","year":"2015","journal-title":"Behav. Sleep Med."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"109","DOI":"10.5664\/jcsm.9566","article-title":"Firefighter sleep: A pilot study of the agreement between actigraphy and self-reported sleep measures","volume":"18","author":"Billings","year":"2022","journal-title":"J. Clin. Sleep Med."},{"key":"ref_35","unstructured":"Morin, C.M. (1993). Insomnia: Psychological Assessment and Management, Guilford Press."},{"key":"ref_36","first-page":"490","article-title":"Beck depression inventory-II","volume":"78","author":"Beck","year":"1996","journal-title":"San Antonio"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"893","DOI":"10.1037\/0022-006X.56.6.893","article-title":"An inventory for measuring clinical anxiety: Psychometric properties","volume":"56","author":"Beck","year":"1988","journal-title":"J. Consult. Clin. Psychol."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"791","DOI":"10.1111\/j.1360-0443.1993.tb02093.x","article-title":"Development of the Alcohol Use Disorders Identification Test (AUDIT): WHO Collaborative Project on Early Detection of Persons with Harmful Alcohol Consumption-II","volume":"88","author":"Saunders","year":"1993","journal-title":"Addiction"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"315","DOI":"10.1016\/0022-3999(94)00125-O","article-title":"The multidimensional Fatigue Inventory (MFI) psychometric qualities of an instrument to assess fatigue","volume":"39","author":"Smets","year":"1995","journal-title":"J. Psychosom. Res."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"357","DOI":"10.1249\/MSS.0b013e3181ed61a3","article-title":"Validation of accelerometer wear and nonwear time classification algorithm","volume":"43","author":"Choi","year":"2011","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"461","DOI":"10.1093\/sleep\/15.5.461","article-title":"Automatic sleep\/wake identification from wrist activity","volume":"15","author":"Cole","year":"1992","journal-title":"Sleep"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1935","DOI":"10.5665\/sleep.5244","article-title":"Benefits of Sleep Extension on Sustained Attention and Sleep Pressure Before and During Total Sleep Deprivation and Recovery","volume":"38","author":"Arnal","year":"2015","journal-title":"Sleep"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"106335","DOI":"10.1016\/j.ssci.2023.106335","article-title":"Daily variation in sleepiness among firefighters while working the 24\/48 and 48\/96 shift schedules","volume":"169","author":"Billings","year":"2024","journal-title":"Saf. Sci."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1093\/sleep\/26.2.117","article-title":"The Cumulative Cost of Additional Wakefulness: Dose-Response Effects on Neurobehavioral Functions and Sleep Physiology From Chronic Sleep Restriction and Total Sleep Deprivation","volume":"26","author":"Maislin","year":"2003","journal-title":"Sleep"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1037\/0021-9010.80.1.43","article-title":"Recovery from work shifts: How long does it take?","volume":"80","author":"Totterdell","year":"1995","journal-title":"J. Appl. Psychol."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"441","DOI":"10.1016\/j.sleep.2004.05.003","article-title":"The impact of extended sleep on daytime alertness, vigilance, and mood","volume":"5","author":"Kamdar","year":"2004","journal-title":"Sleep Med."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"423","DOI":"10.1111\/j.1741-3729.2005.00328.x","article-title":"Behind the Brotherhood: Rewards and Challenges for Wives of Firefighters","volume":"54","author":"Regehr","year":"2005","journal-title":"Fam. Relat."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"1059","DOI":"10.5665\/sleep.2810","article-title":"A Systematic Review Assessing Bidirectionality between Sleep Disturbances, Anxiety, and Depression","volume":"36","author":"Alvaro","year":"2013","journal-title":"Sleep"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"e12869","DOI":"10.1111\/jsr.12869","article-title":"Associations between sleep disturbances, mental health outcomes and burnout in firefighters, and the mediating role of sleep during overnight work: A cross-sectional study","volume":"28","author":"Wolkow","year":"2019","journal-title":"J. Sleep Res."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"e15843","DOI":"10.14814\/phy2.15843","article-title":"Familiarization with ambulatory sleep and blood pressure monitoring is necessary for representative data collection","volume":"11","author":"Kleiber","year":"2023","journal-title":"Physiol. Rep."}],"container-title":["International Journal of Environmental Research and Public Health"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1660-4601\/22\/11\/1678\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,11,5]],"date-time":"2025-11-05T13:30:12Z","timestamp":1762349412000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1660-4601\/22\/11\/1678"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,11,5]]},"references-count":50,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2025,11]]}},"alternative-id":["ijerph22111678"],"URL":"https:\/\/doi.org\/10.3390\/ijerph22111678","relation":{},"ISSN":["1660-4601"],"issn-type":[{"value":"1660-4601","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,11,5]]}}}