Comparison of subjective symptoms associated with exposure to low levels of formaldehyde between students enrolled and not enrolled in a gross anatomy course.

OBJECTIVES: This study aimed to evaluate students' subjective symptoms associated with exposure to low levels of formaldehyde (FA) during a gross anatomy course and to survey how the risk of subjective symptoms was affected by exposure to FA. METHODS: We conducted three questionnaire surveys of 125 students enrolled in an anatomy course (FA exposure group) and 124 students not enrolled in the course (FA nonexposure group) before, during, and 6 months after the course. The questionnaire included questions inquiring about subjective symptoms, sex, age, and allergies. We analyzed differences in the prevalence of subjective symptoms in distinct survey periods. Furthermore, we analyzed the relationship between the subjective symptoms and exposure to FA after adjusting for allergy, sex, and age using multiple logistic regression analysis. RESULTS: The prevalence of some of the ocular, nasal, and nonspecific symptoms in the FA exposure group was low before the course, increased during the course and decreased 6 months after the course. A significant positive relationship was observed between exposure to FA and some symptoms after adjusting for allergy, sex, and age. CONCLUSIONS: We identified some concrete symptoms associated with exposure to FA. We suggest that the exposure to low levels of FA influences students' subjective symptoms.

Investigation of the relationship between convenient visits and doctors' fatigue using burnout and work engagement scales.

OBJECTIVES: Fatigue caused by high workload is often responsible for the high attrition among doctors, and has contributed to a disruption in community medicine. In order to address this problem, institutional mechanisms at the hospital level are required. Previous studies have shown that systemic measures at the hospital level and a change in the mindset of patients can help manage the problem. "Convenient visits" refer to emergency visits for non-emergency problems. It is an avoidable cause of high workload on doctors. Convenient visits also refer to emergency consultation for non-emergency symptoms. As this is a new phenomenon, its relationship with doctors' fatigue needs further research. We investigated the relationship between convenient visits and doctors' fatigue using burnout and work engagement scales. METHODS: We selected 44 hospitals, with >200 beds each, in provincial cities of prefectures with a doctor-population ratio lower than the national average. These cities were considered likely to manifest the phenomenon of 24-hour society and include overworked doctors. Ordinance-designated cities were excluded from this study owing to wide population variability. Three doctors from each hospital were randomly selected from among physicians, surgeons, and pediatricians. We distributed questionnaires (a questionnaire concerning convenient visits, Maslach Burnout Inventory-Human Services Survey, and Utrecht Work Engagement Scale) to 132 doctors. RESULTS: Forty-two doctors responded to the survey. The median proportion of convenient visits among emergency visits was 50%. Sixty percent of the doctors surveyed were annoyed by convenient visits. Other doctors indicated good collaboration between the hospitals and communities or that they were not currently annoyed by convenient visits, although they had been annoyed previously. The emotional exhaustion in doctors, who worked in hospitals that did not restrict convenient visits, was significantly higher than in those who worked in hospitals that restricted these visits. A significant risk of serious burnout was found via crude and multiple logistic regression analysis (adjusted for age and gender, or adjusted for age, gender, clinical department, frequency of work shifts, and sleep duration during work shifts). CONCLUSION: Doctors working in hospitals that do not protect them against convenient visits are more prone to burnout. Although the number of convenient visitors is increasing, many hospitals lack systemic measures to manage them. This contributes to doctors' burnout. We suggest that hospitals control convenient visits for preventing doctors' burnout. Collaboration between hospitals and communities is required to help alleviate this problem.

Advantages of the Variable Shift System, and Effective Use of Break Time to Better Support the Work Engagement of Nurses on Extended Day Shifts.

OBJECTIVES: The aim of this study is to clarify factors that support the work engagement of nurses, who bear the burden of extended day shifts, by focusing on the advantages of the variable shift system and workday break activities. METHODS: Nurses who were working under a variable shift system were asked to complete a self-report questionnaire to examine the workload, work engagement, work stressors, stress-coping strategies, and stress-coping break time activities, as well as the advantages and disadvantages of the variable shift system. Nine break activities were classified into the following four categories: social activities, rest/relaxation, entertainment, and cognitive activities. The advantages or disadvantages of the variable shift system were scored by developing composite variables using principal component analysis. These variables were used to perform a multiple regression analysis with work engagement as the dependent variable. RESULTS: The advantage score was the variable most strongly correlated with work engagement. In contrast, "Quantitative workload" was negatively correlated with work engagement. Among break activities, in the social activities category correlations were observed in "Both conversation and Email/SNS" and "Conversation only". Although in fact most nurses chose conversation as one of the break options, more than half of the nurses selected rest/relaxation as their ideal break activity. CONCLUSION: Our study suggested that the variable shift system supported the work engagement of nurses who worked extended day shifts. The results also suggested that it would be useful to arrange the employee lounge environment so that employees could freely choose between "conversation" or "taking a rest" depending on the circumstances.

The relationship of sleep complaints risk factors with sleep phase, quality, and quantity in Japanese workers.

Numerous studies have determined that lifestyle factors (smoking, drinking, snacking, etc.) and the bedroom environment can influence sleep. We developed a new sleep scale-the 3-Dimensional Sleep Scale (3DSS)-which measures three elements of sleep: phase, quality, and quantity. The purpose of this study is to determine which risk factors of sleep complaints are associated with these sleep elements. Data were obtained from 366 Japanese day workers (302 men and 64 women). Sleep condition was assessed with the 3DSS, and we also assessed various habits within 2 h of going to bed, including smoking, drinking, snacking, caffeine intake, mobile phone use, and working. We also asked about bedroom environmental conditions (noise, lighting, and temperature and humidity). Multivariate logistic regression analysis using the backward selection method (likelihood ratio) was used, with 3DSS scores as the outcome (i.e., over or under the cutoff). The results showed that smoking was associated with significantly greater odds ratio [2.71 (1.65-4.44)] of disordered sleep phase, while lighting as well as temperature and humidity led to greater odds [3.67 (1.55-8.68), 1.93 (1.20-3.11)] of poor sleep quality. Finally, only noise was significantly related to greater odds [1.98 (1.13-3.46)] of low sleep quantity. These findings indicated the various risk factors of sleep complaints could be associated with different sleep elements. This might help in the effective treatment of sleep complaints.

Day workers suffering from a wider range of sleep problems are more likely to experience suicidality.

Both a higher suicide rate and widespread sleep problems are serious health concerns in Japan when compared with those of other countries. We investigated the relationship between suicidal ideation and sleep problems in Japanese day workers using the 3-dimensional sleep scale (3DSS), which measures three sleep elements (phase, quality, and quantity). Data from 635 Japanese day workers (461 mens and 174 womens) were included. The 3DSS was used to assess participants' sleep condition. Participants were classified into eight sleep types based on scores of phase, quality, and quantity: All Good Sleep, Owl (poor phase), Inefficient (poor quality), Short (poor quantity), Owl + Inefficient (poor phase and quality), Owl + Short (poor phase and quantity), Inefficient + Short (poor quality and quantity), and All Poor Sleep. We assessed participants' suicidal ideation using question 19 of the self-rating depression scale (SDS); 119 cases (18.7 %) had ratings of 2-4 for this question and were considered to have suicidal ideation. The higher the number of sleep problems, the higher the risk of suicidal ideation compared to sleep types not indicative of problems. All Poor Sleep had the highest risk of the eight sleep types. Individuals with Owl + Short, Inefficient + Short, or All Poor Sleep had a significant risk of suicidal ideation even after adjusting for hopelessness and nightmares. Our findings suggested that sleep problems assessed by the 3DSS were related to suicidal ideation. Analysis of various aspects of sleep could be helpful for suicide prevention.

[Reliability and validity of the 3 Dimensional Sleep Scale (3DSS)--day workers version--in assessing sleep phase, quality, and quantity].

OBJECTIVES: Most sleep scales assess sleep quantity (e.g., sleep duration and daytime sleepiness) or sleep quality (e.g., sleep latency and maintenance); the Pittsburgh Sleep Quality Index (PSQI) is an exceptional example. However, the prevalence of 24-hour operations presents the need for a scale that can also measure sleep phase (e.g., sleep onset and offset). Furthermore, we have to assess the phase, quality and quantity respectively to understand which of them has a problem. Thus, the 3 Dimensional Sleep Scale (3DSS) - day workers version - was developed to assess each of them related to sleep, and this study attempted to verify its reliability and validity. METHODS: Subjects were 635 day workers (461 men, 174 women; average age = 40.5 years) from the manufacturing and service industries. A scale was created based on a pre-study and discussions with specialists. The scale consisted of 17 sleep-related items. The skew of the data was assessed, and the construct validity and reliability were verified using exploratory and confirmatory factor analysis and Cronbach's alpha, respectively. The scale was scored and G-P analysis was performed. The items measuring phase, quality, and quantity of sleep were selected from the PSQI and SDS, and their correlation with the three scales of 3DSS were measured to verify the convergent and discriminant validity. In addition, the total scores obtained on the PSQI were compared with each scale of the 3DSS. RESULTS: No skew was found in the data. Exploratory factor analysis revealed a three-factor structure--quality, quantity, and phase. Each factor consisted of five items, therefore two items were excluded. The fitness of the 15-item model was better than that of the 17-item model according to confirmatory factor analysis. Cronbach's alpha for phase, quality and quantity score were 0.685, 0.768 and 0.716, respectively. The hypothesis tests were almost accepted, therefore convergent and discriminant validity were sufficiently established. CONCLUSIONS: The present study established the reliability and validity of the 3DSS; however, further studies using larger samples are needed to standardize the test and to establish a cut-off value.

Development of a Scale for Assessing Three Aspects of Sleep: Regularity, Quality, and Quantity.

Objectives: It is difficult to assess sleep habits using one factor (i.e., sleep duration) alone. Regularity and quality of sleep have to be considered to assess sleep accurately. However, to our knowledge there is no scale which scores the three factors simultaneously. The purpose of this study was to inspect the reliability and validity (content, construct, and discriminant validity) of a scale we developed to screen for poor sleep habits. This scale was constructed to assess three aspects of sleep: regularity, quality, and quantity. Methods: Subjects were 563 day workers (370 men and 193 women; average age = 40.4 yr) from the manufacturing and service industries. We created a 21-item questionnaire (7 items for each of 3 factors) based on earlier studies and discussions with specialists. Reliability and construct validity of the questionnaire were assessed through item and factor analyses and Cronbach's alpha. In addition, subjects' scores were using principal component analysis, and subjects were classified according to their scores through a cluster analysis. We compared lifestyles, daytime sleepiness, stress, and chronic disease among the subjects to examine the instrument's discriminant validity. Results: Although our analysis revealed 6 items were invalid, the questionnaire assessed the three factors (regularity, quality and quantity) as expected: Cronbach's alpha was 0.744, 0.757, and 0.548, respectively. Two of the 7 quantity items were identified as assessing regularity instead, but all other items performed as expected. Four items measuring insomnia (disturbance of sleep induction, disturbance of sound sleep, nocturnal awakening, and early morning awakening) included constant burden as a quality factor. Chi-squared tests showed that the ratio of participants who took good care of their health and had less stress and daytime sleepiness was significantly high in the highest-scoring group, while the ratio of people reporting stress and chronic disease was significantly high in the lowest-scoring group. Conclusions: The questionnaire we developed for assessing three factors of sleep (regularity, quality and quantity) was determined to have construct validity. However, since some items were excluded and some assessed into another factor, sufficient reliability and content validity were not found. Revision is needed to improve the scale's accuracy, and we also have to examine detailed discriminant validity controlling for factors such as age and sex.