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Purpose@#: This study aimed to identify the effects of a multifaceted pediatric delirium education program for pediatric intensive care unit (PICU) nurses on their delirium knowledge, confidence in delirium nursing, and delirium evaluation accuracy. @*Methods@#: This study used a one-group pretest-posttest design. The participants were 50 nurses in two units of the PICU at S General Hospital in Seoul. All participants took a 1-hour lecture with case-based practice for the first two weeks, and received feedback as they applied the program to clinical practice over the next two weeks. Test measures were completed before and after the four week intervention period for all participants. The delirium evaluation accuracy was measured using the Korean version of the Cornell Assessment of Pediatric Delirium. Data were analyzed using the chi-square and paired t-tests. @*Results@#: After the Pediatric Delirium Education Program, nurses’ delirium knowledge (x2 =11.65, p =.001), confidence in delirium nursing (t=9.71, p＜.001), and delirium evaluation accuracy (t=6.07, p＜.001) improved significantly. @*Conclusions@#: Pediatric delirium education programs for PICU nurses were effective. For active application of the program in clinical practice in the future, various cases of childhood delirium and specific strategies for each subject must be developed. To achieve this, long-term intervention and research for multiple organizations are required.
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Purpose@#This study aimed to investigate the nationwide intention to delegate clinical practice of medical specialists in accordance with the enactment of the scope of practice for advanced practice nurses (APNs). @*Methods@#Data were collected from October to December 2021 using Google Surveys. In total, 147 medical specialists from 12 provinces responded to the survey. The survey questionnaire was categorized into four legislative draft duties, according to the scope of practice (a total of 41 tasks): Twenty-nine tasks on treatments, injects, etc., performed under the guidance of a physician and other activities necessary for medical treatment (treatment domain); two tasks on collaboration and coordination; six tasks on education, counseling, and quality improvement; four regarding other necessary tasks. Participants were asked whether they were willing to delegate the tasks to APN. @*Results@#The intention to delegate tasks to APN was higher for non-invasive tasks such as blood sampling (97.3%) or simple dressing (96.6%). Invasive tasks such as endotracheal tube insertion (10.2%), sampling: bone marrow biopsy & aspiration (23.8%) showed low intention to delegate in the treatment domain. Participants who were older, male, and had more work careers with APN, showed a higher intention to delegate tasks. @*Conclusion@#To prevent confusion in the clinical setting, a clear agreement on the scope of APN practice as APN delegated by physicians should be established. Based on this study, legal practices that APN can perform legally should be established.
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Purpose@#: This study explores the professional status of Advanced Practice Nurses (APNs) in Korea, who, despite being legally certified, face instability in their professional standing, including their scope of practice and compensation.Method : The study uses Flexner’s professional characteristics as a framework to analyze and project the future trajectory of Korean APNs. @*Results@#: First, to ensure social accountability, professional bodies need to establish uniform nursing policies related to job roles, and healthcare institutions must adhere to these policies. Second, nursing leaders should spearhead the creation of nursing knowledge essential for the profession's advancement, aiming to establish it as the foundation for nursing practice through a consensus process within the nursing community. Third, the curriculum for APNs should enhance the quantitative and qualitative aspects of practice in response to societal needs. Fourth, professional bodies should formulate consistent nursing policies based on a thorough analysis of the healthcare environment and legal considerations, and guide their implementation in clinical practice through a consensus process within the nursing community. Lastly, guidelines should be established for professional standards suitable for the Korean context. @*Conclusion@#: Based on this review, it is recommended that all APNs adhere to the professional standards set by their respective organizations, actively participate in personal quality improvement initiatives, and fulfill their duties and roles as members of these professional bodies. Furthermore, these organizations should devise practical strategies to solidify the APN system and should spearhead a systematic consensus process that garners the agreement of all members within the nursing community.
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Purpose@#: This study aimed to identify and describe the leadership experience of advanced practice nurses (APN). @*Methods@#: Data were collected through five focus group interviews in 2022 with a total of 24 APNs in groups of 4-6 participants. All interviews were recorded, transcribed, and data were analyzed using qualitative content analysis. @*Results@#: Nine categories emerged from three main themes. First, “Roles of APN leadership” comprised a trusted clinical expert, a moderator for the entire team, a resource person for nurturing the next generation, and a change agent for improving clinical practice. Second, “Facilitators and barriers to APN leadership” included ambiguity of APN role, support system, and institutional backing. Third, “Strategies for strengthening APN leadership competencies” comprised systematic leadership education and speaking up for APNs. @*Conclusion@#: APNs are passionate about their expertise and practice, but lack the legal and organizational authority and support to provide successive leadership. Systematic education including leadership and organizational advocacy will enable APN to provide leadership that benefits patients, institutions, and the wider healthcare system.
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Purpose@#This study aimed to identify the early sedation depth in the first 48 hours of mechanical ventilation and its relationship to clinical outcomes to promote the transition to light sedation. @*Methods@#This retrospective single-center cohort study was conducted in two medical intensive care units (MICUs) at a general tertiary hospital, using a standardized sedation protocol. To investigate the early sedation depth, the Sedation Index was used, which can indicate changes over the first 48 hours. Patients were divided into three groups based on tertiles of Sedation Index. The primary outcome was mortality at 30, 90, and 180 days. The secondary outcomes included length of stay in the ICU and ventilator-free days. Kaplan-Meier analysis and multivariable Cox regression were conducted to compare factors influencing mortality. @*Results@#This study included 394 patients. The deepest sedation group showed more severe illness, delirium, and deeper sedation at admission (p < .001). The survival curve decreased as sedation increased, even within the light sedation levels. In the deepest sedation group, 30-day mortality (hazard ratio [HR] 2.11, 95% confidence interval [CI] 1.33–3.34), 90-day mortality (HR 2.00, 95% CI 1.31–3.06), and 180-day mortality (HR 1.77, 95% CI 1.17–2.67) increased. The length of stay in the ICU and ventilator-free days did not show statistical differences. @*Conclusions@#These results indicate that early deep sedation is a modifiable factor that can potentially affect mortality. The protocol for inducing the transition into light sedation must comply with recommendations to improve clinical outcomes.
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Poly Adenylate Binding Protein Interacting protein 1 (PAIP1) plays a critical role in translation initiation and is associated with the several cancer types. However, its function and clinical significance have not yet been described in oral squamous cell carcinoma (OSCC) and its associated features like lymph node metastasis (LNM). Here, we used the data available from Gene Expression Omnibus (GEO), The Cancer Genome Atlas (TCGA), and Clinical Proteomic Tumor Analysis Consortium (CPTAC) to analyze PAIP1 expression in oral cancer. The publicly available data suggests that PAIP1 mRNA and protein levels were increased in OSCC. The high PAIP1 expression was more evident in samples with advanced stage, LNM, and worse pattern of invasion. Moreover, the in vitro experiments revealed that PAIP1 knockdown attenuated colony forming, the aggressiveness of OSCC cell lines, decreasing MMP9 activity and SRC phosphorylation. Importantly, we found a correlation between PAIP1 and pSRC through the analysis of the IHC scores and CPTAC data in patient samples. Our findings suggest that PAIP1 could be an independent prognostic factor in OSCC with LNM and a suitable therapeutic target to improve OSCC patient outcomes.
Subject(s)
Humans , Carcinoma, Squamous Cell/genetics , Head and Neck Neoplasms , Lymphatic Metastasis , Mouth Neoplasms/pathology , Peptide Initiation Factors/metabolism , Prognosis , Proteomics , RNA-Binding Proteins/metabolism , Squamous Cell Carcinoma of Head and NeckABSTRACT
Purpose@#: The purpose of this study was to identify the mediating effect of role clarity in the relationship between clinical decision-making abilities and job stress among advanced practice nurses at tertiary hospitals. @*Methods@#: The participants were 137 advanced practice nurses. The assessment tools were clinical decisionmaking in nursing scale, role ambiguity scale, and Korean occupational stress scale (KOSS-26). Data were analyzed with the SPSS/24.0 program and mediation analysis was performed according to the Baron and Kenny methods. @*Results@#: There were significant relationships between clinical decision-making abilities and job stress (r=-.33, p<.001), and role clarity and job stress (r=-.29, p=.001). Role clarity showed partial mediating effects in the relationship between clinical decision-making abilities and job stress (Z=2.02, p=.043). @*Conclusion@#: Therefore, to reduce advanced practice nurses’ job stress, it is necessary to develop a program and strategies to increase their clinical decision-making abilities.
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This study aims to examine the clinical differences between objective short sleep insomniacs (OSSI) and subjective short sleep insomniacs (SSSI). Methods: We enrolled 79 patients (aged 27–74 years) with chronic insomnia disorder (CID) who underwent overnight polysomnography (PSG) and completed sleep-related questionnaires as well as habitual sleep time. All of them completed actigraphy (ACT) recording for one week prior to the PSG study. Objective sleep duration for one-week average sleep was calculated by ACT, and subjective sleep duration was counted through self-reported habitual sleep time. We divided the subjects into three groups; OSSI (<6 hight), SSSI (objective sleep ≥6 hight and subjective sleep <6 h/ night), and normal sleep duration insomniacs (NSDI, subjective sleep ≥6 hight). Results: The three groups namely OSSI, SSSI, and NSDI had 25 (31.6%), 36 (45.6%), and 18 (22.8%) subjects, respectively. The SSSI were significantly older and had higher daytime sleepiness than the OSSI. According to the PSG results, the OSSI showed shorter sleep latency (11.86 min vs. 39.69 min) and N2 sleep % (59.43% vs. 67.96%), and longer rapid eye movement sleep % (20.79% vs. 15.47%) than that in the NSDI. There was no difference in treatment response between groups. Conclusions: 45.6% of CID patients underestimated their sleep relative to objective sleep. However, there were no differences in total sleep time on PSG between groups. The OSSI showed younger age and more daytime sleepiness, and the SSSI showed poorer sleep quality than the NSDI. These findings suggest that long-term ACT recording in a casual environment would be useful to monitor objective sleep in patients with CID, particularly, in subjectively short sleep insomniacs.
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This study aimed to investigate the prevalence of symptoms of shift work disorder (SSWD) and its related factors in rapidly rotating three-shift nurses. Methods: We enrolled 344 nurses (mean age, 28.7 years) without prior history of sleep disturbance before starting shift work in a university-affiliated hospital. SSWD were defined using self-reported sleep questionnaires (insomnia severity index >14 and/or Epworth Sleepiness Scale ≥10) and without any sleep problem before shift work. Sleep pattern in each of the three shifts was measured using the Munich Chronotype Questionnaire for Shift-Workers. Mood (anxiety, depression) and job stress were also measured using self-reported questionnaires. Results: Our results showed that 62.2% of the participants presented SSWD. Compared to the non-SWD group, the SSWD group showed worse sleep hygiene, lower total sleep time (TST) during workdays, higher anxiety and depressive mood, and higher job stress. In the SSWD group, the evening chronotype individuals presented the shortest TST during day shifts, while the morning chronotype individuals presented the shortest TST during evening shifts. Conclusions: SSWD is highly prevalent in fast rotating three-shift nurses. This study suggests that intensive education on sleep hygiene and appropriate scheduling of shift work while considering individual chronotypes may improve sleep patterns and sleep quality of shift workers and minimize SSWD.
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Purpose@#The purpose of this study was to apply patient-engaged bedside handoffs in comprehensive care units, and to evaluate the effects of bedsides to nurses and patients. @*Methods@#This study employed a cluster randomized cross-over design.Electrical Medical Record (EMR)-based handoffs and patient-engaged bedside handoffs were alternatively applied to 104 patients, who were assigned to a total of 30 clusters (nursing handoff teams) in 4 comprehensive care units at the S medical center in Seoul, and the patients evaluated each type of handoffs. A total of 139 nurses were also participated in the same units and evaluated each type of handoffs. Data were analyzed using t-test, Wilcoxon rank sum test, ANOVA, and Kruskal-Walls test. @*Results@#The patient's satisfaction of the patient-engaged bedside handoffs was higher than that of the EMR-based handoffs (Z=-5.16, p<.001). On the other hand, the nurse's satisfaction of the patient-engaged bedside handoffs was significantly lower than that of the EMR-based handoffs (t=13.21, p<.001). There were no differences in length of the reporting time between two types of handoffs (t=-0.48, p=.634). @*Conclusion@#Patient satisfaction with the patient-engaged bedside handoffs was higher than that of EMR-based handoffs, and nurses' satisfaction with the patient-engaged bedside handoffs was significantly lower than that of EMR-based handoffs. Future studies are needed regarding the impacts of patient-engaged bedside handoffs on the quality of healthcare by identifying the benefits of the handoffs.
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Objectives@#Sleep issues are more prevalent in healthcare workers compared to workers in other industries. This study investigated sleep-wake pattern, sleep quality, and daytime status in hospital workers using a Galaxy Watch3 (GW3), a wrist-worn device that uses an accelerometer and heart rate sensor to distinguish sleep and wakefulness. @*Methods@#Multiple sleep parameters including total sleep time (TST) were obtained using a GW3. The Epworth sleepiness scale (ESS), insomnia severity index (ISI), Pittsburgh sleep quality index (PSQI), and bedtime procrastination scale (BPS) were used to assess participants’ status. @*Results@#A total of 70 daytime hospital workers (male, 45.7%; mean age, 35.66±7.79 yr) participated in the monitoring of their sleep-wake patterns for 30 consecutive days. Participants had a mean ESS of 8.14±3.62, ISI of 6.13±3.83, and PSQI of 4.86±2.14. The mean TST was 5.75±0.74 hr (range: 3.42–6.88) during workdays and 5.92±0.92 hr (range: 2.87–8.25) during free days. Chronotype (mid-sleep on freedays corrected for sleep debt accumulated over the work week) was 3.60±1.03 clock hr (range: 1.84–6.69). BPS was negatively correlated with age (rho=-0.27, p=0.022), TST of workdays (rho=-0.53, p<0.001), and TST of free days (rho=-0.43, p<0.001). A higher BPS was associated with larger social jetlag (rho=0.28, p=0.018) and later chronotype (rho=0.41, p<0.001). @*Conclusions@#In this study, 91.5% of daytime hospital workers suffered from chronic sleep insufficiency (<7 hr during both workdays and free days) although their daytime sleepiness or subjective sleep were not poor. Individuals with a later chronotype had poorer sleep quality and worse sleep procrastination behavior.
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Objective@#Organic light-emitting diodes (OLEDs) emit less blue light than traditional light-emitting diodes (LEDs), and we previously found that early-night OLED light exposure (LE) delays the melatonin phase by less than LED at a color temperature of 4,000 K. As a follow-up study, we investigated the effects of OLED and LED at a different color temperature (3,000 K) on melatonin profile, sleep, and vigilance. @*Methods@#24 healthy subjects (27.5±5.1 years) were exposed to three light conditions [OLED, LED, and dim light (DL)] from 17:30 to 24:00, in a random order and with a 1-week interval. Saliva samples for melatonin were taken every hour from 18:00 to 24:00. Polysomnography (PSG) and a psychomotor vigilance test (PVT) were performed. @*Results@#Melatonin onset time was significantly delayed under OLED and LED compared with DL, with no significant difference between OLED and LED. The mean melatonin level at 24:00 under LED was lower than that under DL, but there was no significant difference between OLED LE and DL. The percentage of slow wave sleep (N3) in LED was significantly lower than in OLED. @*Conclusion@#Exposure to light in the evening can suppress melatonin secretion late at night and disturb deep sleep, and those effects are slightly worse under LED than OLED.
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Objectives@#Light at night (LAN) can suppress melatonin secretion and thus disturb normal sleep. The aim of this study was to investigate how the illumination of a smartphone at bedtime affects the circadian rhythm and sleep in patients with insomnia. @*Methods@#We recruited two middle-aged patients (one day worker and one shift worker) with insomnia. They used a smartphone more than 12 hours a day, particularly at bedtime. This was a crossover design study, and each patient spent a night at the light control unit twice at a one-week interval, with or without smartphone use. Patients were instructed to look at a smartphone (5–10 lux) under 150 lux of ceiling illumination from 18:00 until lights-off. During the night, without a smartphone, they read a book or newspaper. Saliva was collected every 30 minutes and analyzed for melatonin. Sleep was monitored by polysomnography. @*Results@#The day worker showed a delayed dim light melatonin onset time (DLMO) (21:30 vs. 22:00) and a 38.7% decrease in melatonin levels with smartphone use. For the shift worker, both melatonin and cortisol showed abnormal patterns, and thus DLMO was not determined in either condition. In the day worker, shorter rapid eye movement (REM) latency and increased REM were observed with smartphone use. @*Conclusions@#This study demonstrates that the use of smartphones at bedtime acutely suppresses melatonin secretion and delays the sleep-wake cycle. However, the effect of LAN on melatonin secretion was not apparent in the shift worker with already misaligned circadian rhythm.
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Purpose@#: The purpose of this study was to understand and describe the experiences of the advanced nurse practitioner (APN) system used by healthcare providers including APNs, doctors who worked with APNs, and APN master’s course professors at a graduate school. @*Methods@#: Qualitative data were collected via snowball sampling. The participants were nine APNs, six doctors, and three professors. They were divided into three focus groups, each of which consisted of all three types of healthcare providers. Data were collected via interviews with the three focus groups conducted from September to October 2019. All interviews were audiotaped and transcribed verbatim. The transcribed data then underwent qualitative content analysis. @*Results@#: Based on the data, we extracted four themes and 14 categories. The themes were “Role and system of APNs started according to healthcare environment changes”, “Optimal healthcare provider to ensure quality of care”, “Confused role and system of APNs due to incomplete medical law”, and “Tasks for the stable operation of the APN system.” @*Conclusion@#: For quality treatment and safety of patients, a legal basis must be established for the APN system. For its stable operation, social consensus regarding legislation about APNs’ scope of practice is required. Finally, a discussion is necessary about the integration of APNs’ 13 fields.
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Purpose@#The purpose of this study was to investigate the sleep duration, social jetlag (SJL), and subjective sleep disturbance according to the individual chronotype in rotating shift nurses. @*Methods@#A total of 344 rotating 3-shift nurses (mean age 28.67 years) were recruited at one university affiliated hospital. They completed the following questionnaires, which were used to assess their chronotype and sleep: the morningness-eveningness questionnaire (MEQ), self-reported sleep duration of work days (SDW shift) and free days (SDF shift) in each shift (day [D], evening [E], night [N]), and sleep disturbance (Insomnia severity index, ISI). SJL shift was calculated as the difference in midsleep (MS = sleep onset+1/2 sleep duration) between work days (MSW) and free days (MSF). @*Results@#Subjects were divided into 3 chronotype groups according to the MEQ; morning (MG, 4.4%) intermediate (IG, 57.8%), and evening groups (EG, 37.8%). SDW D was shortest (4.68 hr) and SDF E was longest (8.93 hr) in the EG. SJL D was longest in the EG (3.77 hr), and SJL N was longest in the MG (7.37 hr). The prevalence of sleep disturbance was 33.3% (MG), 29.6% (IG), and 40.0% (EG), respectively, without any statistical significance. @*Conclusion@#In order to improve the sleep of shift workers, it is recommended that the evening chronotypes should reduce the day shifts and the morning chronotypes should reduce the night shifts. We also propose a study to determine whether these shift assignments can improve the sleep in shift nurses.
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Objective@#Organic light-emitting diodes (OLEDs) emit less blue light than traditional light-emitting diodes (LEDs), and we previously found that early-night OLED light exposure (LE) delays the melatonin phase by less than LED at a color temperature of 4,000 K. As a follow-up study, we investigated the effects of OLED and LED at a different color temperature (3,000 K) on melatonin profile, sleep, and vigilance. @*Methods@#24 healthy subjects (27.5±5.1 years) were exposed to three light conditions [OLED, LED, and dim light (DL)] from 17:30 to 24:00, in a random order and with a 1-week interval. Saliva samples for melatonin were taken every hour from 18:00 to 24:00. Polysomnography (PSG) and a psychomotor vigilance test (PVT) were performed. @*Results@#Melatonin onset time was significantly delayed under OLED and LED compared with DL, with no significant difference between OLED and LED. The mean melatonin level at 24:00 under LED was lower than that under DL, but there was no significant difference between OLED LE and DL. The percentage of slow wave sleep (N3) in LED was significantly lower than in OLED. @*Conclusion@#Exposure to light in the evening can suppress melatonin secretion late at night and disturb deep sleep, and those effects are slightly worse under LED than OLED.
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Purpose@#: The purpose of this study was to understand and describe the experiences of the advanced nurse practitioner (APN) system used by healthcare providers including APNs, doctors who worked with APNs, and APN master’s course professors at a graduate school. @*Methods@#: Qualitative data were collected via snowball sampling. The participants were nine APNs, six doctors, and three professors. They were divided into three focus groups, each of which consisted of all three types of healthcare providers. Data were collected via interviews with the three focus groups conducted from September to October 2019. All interviews were audiotaped and transcribed verbatim. The transcribed data then underwent qualitative content analysis. @*Results@#: Based on the data, we extracted four themes and 14 categories. The themes were “Role and system of APNs started according to healthcare environment changes”, “Optimal healthcare provider to ensure quality of care”, “Confused role and system of APNs due to incomplete medical law”, and “Tasks for the stable operation of the APN system.” @*Conclusion@#: For quality treatment and safety of patients, a legal basis must be established for the APN system. For its stable operation, social consensus regarding legislation about APNs’ scope of practice is required. Finally, a discussion is necessary about the integration of APNs’ 13 fields.
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Purpose@#The purpose of this study was to investigate the sleep duration, social jetlag (SJL), and subjective sleep disturbance according to the individual chronotype in rotating shift nurses. @*Methods@#A total of 344 rotating 3-shift nurses (mean age 28.67 years) were recruited at one university affiliated hospital. They completed the following questionnaires, which were used to assess their chronotype and sleep: the morningness-eveningness questionnaire (MEQ), self-reported sleep duration of work days (SDW shift) and free days (SDF shift) in each shift (day [D], evening [E], night [N]), and sleep disturbance (Insomnia severity index, ISI). SJL shift was calculated as the difference in midsleep (MS = sleep onset+1/2 sleep duration) between work days (MSW) and free days (MSF). @*Results@#Subjects were divided into 3 chronotype groups according to the MEQ; morning (MG, 4.4%) intermediate (IG, 57.8%), and evening groups (EG, 37.8%). SDW D was shortest (4.68 hr) and SDF E was longest (8.93 hr) in the EG. SJL D was longest in the EG (3.77 hr), and SJL N was longest in the MG (7.37 hr). The prevalence of sleep disturbance was 33.3% (MG), 29.6% (IG), and 40.0% (EG), respectively, without any statistical significance. @*Conclusion@#In order to improve the sleep of shift workers, it is recommended that the evening chronotypes should reduce the day shifts and the morning chronotypes should reduce the night shifts. We also propose a study to determine whether these shift assignments can improve the sleep in shift nurses.
ABSTRACT
Objectives@#Light at night (LAN) can suppress melatonin secretion and thus disturb normal sleep. The aim of this study was to investigate how the illumination of a smartphone at bedtime affects the circadian rhythm and sleep in patients with insomnia. @*Methods@#We recruited two middle-aged patients (one day worker and one shift worker) with insomnia. They used a smartphone more than 12 hours a day, particularly at bedtime. This was a crossover design study, and each patient spent a night at the light control unit twice at a one-week interval, with or without smartphone use. Patients were instructed to look at a smartphone (5–10 lux) under 150 lux of ceiling illumination from 18:00 until lights-off. During the night, without a smartphone, they read a book or newspaper. Saliva was collected every 30 minutes and analyzed for melatonin. Sleep was monitored by polysomnography. @*Results@#The day worker showed a delayed dim light melatonin onset time (DLMO) (21:30 vs. 22:00) and a 38.7% decrease in melatonin levels with smartphone use. For the shift worker, both melatonin and cortisol showed abnormal patterns, and thus DLMO was not determined in either condition. In the day worker, shorter rapid eye movement (REM) latency and increased REM were observed with smartphone use. @*Conclusions@#This study demonstrates that the use of smartphones at bedtime acutely suppresses melatonin secretion and delays the sleep-wake cycle. However, the effect of LAN on melatonin secretion was not apparent in the shift worker with already misaligned circadian rhythm.
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Background@#and Purpose: Organic light-emitting diodes (OLEDs) emit less blue light than traditional light-emitting diodes (LEDs), but the effects of OLED light exposure (LE) on melatonin and sleep have not been evaluated. @*Methods@#Twenty-four healthy subjects (age 26.9±5.7 years; including 18 females) with the intermediate chronotype were exposed to three different light conditions [4,000 K 150 lux OLED LE, 4,000 K 150 lux LED LE, and dim light (DL) at <10 lux] for 6.5 h from 17:30 to 24:00, in a random order and with a 1-week interval. Participants entered the unit for the experiment at 16:00, and their daylight was measured by actigraphy from 8:00 to 16:00 during each session. Saliva samples for melatonin were taken every hour from 18:00 to 24:00. Sleep was monitored by polysomnography, and vigilance was evaluated by psychomotor vigilance test upon awakening. @*Results@#Melatonin onset occurred at 21:11±01:24, 21:20±01:19, and 21:36±01:16 in the DL, OLED, and LED conditions, respectively. Melatonin onset was significantly delayed under LED LE compared to DL (p=0.007) but did not differ under OLED LE (p=0.245). Melatonin suppression, sleep parameters, and vigilance were similar among the three light conditions. The accumulated amount of daytime light in each session was negatively correlated with the melatonin onset time under the DL (rho=-0.634, p=0.002) and OLED (rho=-0.447, p=0.029) conditions, not under the LED condition (p=0.129). @*Conclusions@#Melatonin onset under OLED LE was not significantly delayed compared to DL.Exposure to sufficient daylight may advance melatonin onset even when a subject is exposed to OLED LE in the evening.