Interactive effect of individual factors on nurses' health and sleep

There is a tendency in studies concerning individual diferences in shiftwork tolerance to analyse the moderating effect of individual factors separately as if they acted independently. The aim of this study was to examine the interactive effect of individual factors (i.e. morningness, flexibility, languidity, neuroticism, extroversion) on nurses' health and sleep. A hundred female nurses (mean age 25.9 years, SD = 3.7 years) working a 2 × 12-h shift system were chosen from a larger study conducted among Intensive Care Unit staff. All subjects completed the Standard Shiftwork Index. Multiple regression analyses show that interactions of neuroticism and other factors (languidity, morningness) predict the majority of health and sleep complaints rather than neuroticism itself. Correlation analyses revealed that the interaction of neuroticism and languidity correlates higher with some indices of impaired health and sleep disturbances than when these factors are taken separately. The contribution of flexibility together with extroversion in interactions with neuroticism, and with neuroticism and languidity weaken the relations of languidity and neuroticism with health and sleep indices. The results show that some individual features tend to strengthen or counteract one another in relation to symptoms of shiftwork intolerance.     

Is tolerance to shiftwork predictable from individual difference measures?

Abstract

This study was aimed at evaluating the most important relations between individual characteristics of shiftworkers and their subjective health complaints, obtained by cross-sectional and longitudinal procedures. A total of 604 shiftworkers and 185 young subjects who were going to enter shiftwork were examined by means of individual difference and subjective health questionnaires. The questionnaires were administered concurrently to the group of workers already involved in shiftwork. In the other group studied, the questionnaires were administered before they entered shiftwork, and subjective health was re-examined after the first and third year of work on shifts. More health complaints were reported by the group of older workers and those with longer shiftwork experience, with higher scores of neuroticism, hard-driving and competitiveness, speed and impatience, and rigidity of sleeping habits, and lower scores on relaxedness, efficiency and vigorousness. However, the correlations between these dimensions, when taken before entering shiftwork, and subjective health complaints obtained after a few years working on shifts were small or absent, indicating low validity of the individual difference measures for predicting subsequent health problems in shiftworkers.     

Shiftwork locus of control: Scale development

Abstract

Shiftwork is a significant feature of occupational life for many people. It can have disruptive effects on sleep, health, social activity and performance. It is likely that beliefs about personal control will influence the individual-shiftwork relationship. This paper has two aims; first, to put forward the thesis that shiftwork-specific personal control expectancies may moderate the disruptive impact of shiftwork, and second, to report the development and preliminary validation of a shiftwork-specific locus of control scale. The scale demonstrated satisfactory psychominary qualities in terms of factor structure, internal reliability, construct validity and test-retest reliability. Variables associated with better coping with shiftwork such as alertness, flexibility of sleeping habits and the structured use of time correlated positively with shiftwork locus of control. In contrast, shiftwork locus of control was found to be inversely related to shiftwork problems such as sleep disturbance, poor mental well-being and work stress.     

Is tolerance to shiftwork predictable from individual difference measures?

This study was aimed at evaluating the most important relations between individual characteristics of shiftworkers and their subjective health complaints, obtained by cross-sectional and longitudinal procedures. A total of 604 shiftworkers and 185 young subjects who were going to enter shiftwork were examined by means of individual difference and subjective health questionnaires. The questionnaires were administered concurrently to the group of workers already involved in shiftwork. In the other group studied, the questionnaires were administered before they entered shiftwork, and subjective health was re-examined after the first and third year of work on shifts. More health complaints were reported by the group of older workers and those with longer shiftwork experience, with higher scores of neuroticism, hard-driving and competitiveness, speed and impatience, and rigidity of sleeping habits, and lower scores on relaxedness, efficiency and vigorousness. However, the correlations between these dimensions, when taken before entering shiftwork, and subjective health complaints obtained after a few years working on shifts were small or absent, indicating low validity of the individual difference measures for predicting subsequent health problems in shiftworkers.     

Shiftwork locus of control: Scale development

Shiftwork is a significant feature of occupational life for many people. It can have disruptive effects on sleep, health, social activity and performance. It is likely that beliefs about personal control will influence the individual-shiftwork relationship. This paper has two aims; first, to put forward the thesis that shiftwork-specific personal control expectancies may moderate the disruptive impact of shiftwork, and second, to report the development and preliminary validation of a shiftwork-specific locus of control scale. The scale demonstrated satisfactory psychominary qualities in terms of factor structure, internal reliability, construct validity and test-retest reliability. Variables associated with better coping with shiftwork such as alertness, flexibility of sleeping habits and the structured use of time correlated positively with shiftwork locus of control. In contrast, shiftwork locus of control was found to be inversely related to shiftwork problems such as sleep disturbance, poor mental well-being and work stress.     

Sleep and napping in young shiftworkers: A 5-year follow-up

Abstract

The present study examined sleep characteristics in young workers who entered rapidly rotating shiftwork for the first time and stayed on shifts for 5 years. Data were collected when the subjects had shiftwork experience of approximately 1.5, 3.5 and 5.5 years and a mean age of 22, 24 and 26 years. Data are presented showing significant differences in the main sleep durations between situations within the shift cycle and a small reduction in overall sleep over the observed period, primarily due to a sleep reduction on afternoon shift days. Data on sleep quality did not show any change over this early period of shiftwork exposure. In addition, napping strategies did not change, with the exception of a small increase in those taking naps on night-shift days between 1.5 years and 3.5 years of shiftwork exposure. At all the observed phases there were more young shiftworkers taking a nap on the morning shift days than on the night-shift days. The data suggested that reduced sleeps on morning and night-shift days were not compensated by taking a nap, but rather with an increase in main sleep duration on afternoon shift days and days off. A weak tendency for individuals to be relatively long or short sleepers irrespective of sleep conditions could be seen.     

Changes in the structure of health complaints as related to shiftwork exposure

Abstract

Factor analyses of health complaints in groups with different length of shiftwork exposure show that the structure of these complaints changes with increasing shift experience, indicating the emergence of a shift-specific pattern of health complaints. After about 15 years of shiftwork, complaints related to disturbances of circadian-controlled functions can be found in the first factor whereas other complaints have their dominant loadings on a separate factor, representing general, non-shift-specific impairments. The results indicate that in this way shift-specific components of health impairment can be separated from other non-shift related components.     

The mediating role of work-to-family conflict in the relationship between shiftwork and depression

Abstract

With significant segments of the working population involved in shiftwork, there is the possibility of serious health outcomes. There are two possible pathways to ill health. In the biological pathway the body's circadian rhythms are affected, leading to physiological disturbances and the inability to cope. By contrast, the aim of this study is to elucidate a social pathway by which shiftwork may lead to mental ill health. It examines the mediating influence of work-to-family conflict in the association between shiftwork and depression. Gender differences are also investigated. The sample included 2,931 Canadian respondents with a spouse and at least one child living at home. Close to 28% of respondents were involved in some form of shiftwork. Structural equation modelling supported partial mediation through work-to-family conflict. Further analyses found that mediation was supported in sub-samples of male and female respondents. The results, however, suggest that the experience of shiftwork is quite similar for men and women as no significant differences were found between mediating models. Overall, the findings support the social explanation of the effect of shiftwork on mental health, but they do not rule out other social or biological pathways.     

Personality factors predicting changes in shift work tolerance: A longitudinal study among nurses working rotating shifts

Abstract

The aim of the present study was to investigate the relationship between personality factors (hardiness, morningness, flexibility, and languidity) and longitudinal changes on different measures of shift work tolerance (fatigue, sleepiness, anxiety and depression) over one year among nurses working rotating shifts. A total of 642 female Norwegian nurses working in a rotating three-shift schedule participated in the study. The cohort was established by age-stratified selection among members of the Norwegian Nurses Association in 2008. Questionnaires were administered in 2008/2009 (T1) and in 2009/2010 (T2). The results showed that hardiness was negatively related to fatigue, anxiety and depression at T2 when controlling for the scores on these constructs at T1. Morningness was not related to any indicators of shift work tolerance at T2 when controlling for shift work tolerance at T1. Flexibility was negatively related to anxiety at T2 when controlling for anxiety at T1. Languidity was positively related to sleepiness and fatigue at T2 when controlling for sleepiness and fatigue at T1. The findings indicate that personality factors, especially hardiness, can predict changes related to shift work tolerance over a period of one year.     

Machine Pacing and Shiftwork

Machine-paced work and shiftwork are highly prevalent working conditions commonly believed to have adverse individual and organizational consequences. This article examines the empirical evidence for such effects, and acknowledges the conceptual and methodological problems which have clearly plagued pacing and shiftwork researchers. The literature on pacing while suggestive of overall health and performance effects indicates that the magnitude of such effects are in all likelihood situationally and invididually determined. Very little is known, however, about such interactions. Similarly, the shiftwork literature is contradictory and inconclusive. Shiftwork appears to affect both the quality and quantity of sleep and to disrupt a wide range of physiological and behavioral circadian rhythms. The long-term consequences of these effects are still not known.     

Psychophysical conditions of air traffic controllers evaluated by the standard shiftwork index

Abstract

In the ambit of a large epidemiological survey on the Italian population of air traffic controllers, an evaluation of their health conditions was carried out using the Standard Shiftwork Index (SSI). The study took into consideration 572 male air traffic controllers, aged between 23 and 59 years, of whom 301 were engaged in three large Regional Centres, 189 in thirteen Airport Towers and 82. formerly active controllers, were working in administrative offices. The former controllers showed worse health levels, in particular minor psychological disorders and chronic fatigue. Sixteen of them had been transferred to administrative jobs because of health impairment, owing to severe diseases of the nervous, gastrointestinal and cardiovascular systems. Such disorders, and musculoskeletal ones, were mostly reported by the active controllers. The controllers engaged in Regional Centres showed more sleep disturbances than those engaged in towers. Beside age, some personal characteristics appeared to influence health and well-being. Neuroticism was correlated with chronic fatigue, digestive and cardiovascular complaints, minor psychological disorders, cognitive and somatic anxiety. On the other hand, morningness was correlated negatively with sleep disturbances on morning shift, and positively with sleep duration both on morning shift and rest days.     

Health, well-being and burnout of ICU nurses on 12- and 8-h shifts

It is generally agreed that some features of shift systems can influence the extent of well-being and health problems experienced by the workers involved. Extended working days (9-12 h) have been found to aggravate some problems associated with shiftwork, especially when the work is mentally and emotionally demanding. The aim of the study was to compare measures of health, sleep, psychological and social well-being, job satisfaction and burnout of ICU nurses on 12- and 8-h shifts. The groups of subjects were matced for age, length of shiftwork experience, marital status and number of hours worked. the 12-h shift nurses, when compared to their 8-h shift colleagues, experienced more chronic fatigue, cognitive anxiety, sleep disturbance and emotional exhaustion. Job satisfaction seems to be independent of the shift duration. The nurses on 12-h shifts reported less social and domestic disruption than those on 8-h shifts. The 12-h shift nurses showed worse indices of health, well-being and burnout tan the 8-h shift nurses. It is suggested that this may be associated with their longer daily exposure to the stress of work. The increased number of rest days of 12-h shift nurses seems tobe insufficient to dissipate the adverse health and well-being effects that built up over their longer shifts.     

Working shifts—different effects for women and men?

Abstract

Results are reported of a survey on the effects of shiftwork on women and men working rotating shifts under comparable job conditions. Discriminant analyses revealed that gender-related effects of shiftwork could not be found. However, off-the-job work stress, e.g. a gender-related unequal division of domestic duties, clearly differentiated between women and men and the presence or absence of children in the house. The ‘double burden’ for women, in particular for those with children, did not result in more severe psychosocial or subjective health impairments.     

Increasing flexibility in shiftwork arrangements

Abstract

Renewed interest in increasing flexibility in working time arrangements derives from both social and economic changes. The dominant reasons for greater flexibility in shiftwork arrangements relate to diverse business demands resulting from competitive pressures and rapid technological change, modern workers' personal preferences about the timing of work, and the reduction in hours of work. Many new patterns are applied to meet these demands. A review of innovative patterns reveals their close link with shorter working hours and diversifying career needs. Typical patterns include (a) hours averaging schemes, (b) flexible daily hours, (c) individualized free time schemes. (d) flexitime plus shift systems, (e) a combination of full-time and part-time systems, (f) job sharing, (g) temporary transfer to day work, and (h) career break schemes. Attention is drawn to multi-skilling of workers associated with more independent responsibility and closer communication. Changes to a flexible pattern are usually a result of consultations that respond to the conflicting interests of employers and workers. Support is necessary for a process of informed joint planning. Particularly useful are: (1) identification of operational demands and individual preferences about increasing flexibility in work schedules; (2) presentation of available options with information on implications for workers' health and social life; and (3) facilitating training and group consultation. The adjustments required depend greatly on how the tasks of individual workers are reorganized. In increasing the flexibility of shift schedules, it is important to learn from positive experiences of joint optimization of work content and working time arrangements.     

Does 'hardiness' predict adaptation to shiftwork?

This longitudinal study examined whether the dimensions of hardiness (commitment, control and challenge) predicted psychological symptoms and dissatisfaction with shiftwork, and whether or not the relationships identified were confounded with neuroticism and extraversion. Female nurses were studied during their first 15 months of shiftwork. Thirty-six nurses worked on a 2-shift (day and evening) schedule throughout and 66 transferred from the 2-shift schedule to a 3-shift (day, evening and night) schedule after 6 months. Hardiness, neuroticism, extraversion and symptoms were measured before the respondents began shiftwork (Stage 1). Symptoms and dissatisfaction were measured after 6 months (Stage 2) and 15 months (Stage 3). Multiple regressions indicated that the hardiness dimensions did not predict dissatisfaction at Stages 2 or 3, or symptoms at Stage 3. They also failed to buffer the effect of night-work on symptoms. However, commitment did predict symptoms at Stages 1 and 2 and challenge predicted symptoms at Stage 2. Although these effects were confounded with neuroticism, commitment showed weak evidence of independent prediction. In general, hardiness was a very poor predictor of shiftwork tolerance.     

Changes in the structure of health complaints as related to shiftwork exposure

Factor analyses of health complaints in groups with different length of shiftwork exposure show that the structure of these complaints changes with increasing shift experience, indicating the emergence of a shift-specific pattern of health complaints. After about 15 years of shiftwork, complaints related to disturbances of circadian-controlled functions can be found in the first factor whereas other complaints have their dominant loadings on a separate factor, representing general, non-shift-specific impairments. The results indicate that in this way shift-specific components of health impairment can be separated from other non-shift related components.     

Changes in the structure of health complaints as related to shiftwork exposure

Factor analyses of health complaints in groups with different length of shiftwork exposure show that the structure of these complaints changes with increasing shift experience, indicating the emergence of a shift-specific pattern of health complaints. After about 15 years of shiftwork, complaints related to disturbances of circadian-controlled functions can be found in the first factor whereas other complaints have their dominant loadings on a separate factor, representing general, non-shift-specific impairments. The results indicate that in this way shift-specific components of health impairment can be separated from other non-shift related components.     

Is there an optimum number of night shifts? Relationship between sleep,health and well-being

Abstract

By concentrating on the impact of a specific shift-system feature on the well-being of those concerned, rather than on the impact of the shift system as a whole, one might be able to offer more meaningful suggestions as to what constitutes a better form of shift system. The present study focused on the impact of the number of consecutive night shifts worked on the health and well-being of two groups of nurses (permanent night and rotating shift). All nurses completed a copy of the Standard Shiftwork Index, which is a set of questionnaires designed for comparing the effects of different types of shift system on large groups of workers. It includes measurements of psychological ill-health, physical ill-health, chronic fatigue, social and domestic disruption, attitudes towards shiftwork, sleep quality and sleep habits. Results showed clearly the impact of the number of consecutive nights worked on health and well-being, not directly, but indirectly through the impact on sleep duration and sleep quality. Sleep duration was shown to increase with more consecutive nights worked. This in turn was found to predict sleep quality, which in turn was found to be the stronger direct predictor of psychological and physical ill-health: i.e. better health was associated with longer and better quality sleeps. Explanations in terms of circadian adaptation are discussed.