Norbert K. Semmer

A meta-analysis of work-family conflict and various outcomes with a special emphasis on cross-domain versus matching-domain relations.

A literature review of studies analyzing work-family conflict and its consequences was conducted, and 427 effect sizes were analyzed meta-analytically. Work-family conflict was analyzed bidirectionally in terms of work interference with family (WIF) and family interference with work (FIW). We assessed 3 categories of potential outcomes: work-related outcomes, family-related outcomes, and domain-unspecific outcomes. Results show that WIF and FIW are consistently related to all 3 types of outcomes. Both types of interrole conflict showed stronger relationships to same-domain outcomes than to cross-domain outcomes. Thus, WIF was more strongly associated with work-related than with family-related outcomes, and FIW was more strongly associated with family-related than with work-related outcomes. In moderator analyses, parenthood could not explain variability in effect sizes. However, time spent at work did moderate the relationships between WIF and family-related outcomes, as well as FIW and domain-unspecific outcomes.

The diagnostic accuracy of magnetic resonance imaging, work perception, and psychosocial factors in identifying symptomatic disc herniations

Study Design This was a prospective study of patients (study group) with symptomatic disc herniations and asymptomatic volunteers (control group) matched for age, sex, and work-related risk factors. Objective To determine the prevalence of disc herniation in a matched group of asymptomatic volunteers and to access the diagnostic accuracy of magnetic resonance imaging, work perception, and psychosocial factors in identifying symptomatic disc herniations. Summary of Background Data Disc herniations have been reported to occur in 20–36% of asymptomatic volunteers. A valid comparison of asymptomatic individuals and patients with disc herniations has not been performed. Methods Forty-six patients with low back pain and sciatica severe enough to require a disceclomy were compared with 46 age-, sex-, and risk factor-matched (heavy lifting, twisting and bending, vibration, and sedentary activity) asymptomatic voluteers. Both groups had a complete clinical and magnetic resonance imaging examination and completed a questionnaire to assess differences in the psychosocial and work perception profiles. The prevalence and the severity of morphologic alterations (disc herniation, disc degeneration, and neural compromise) was analyzed by two independent radiologists in a blinded fashion. Differences between both groups regarding MRI findings, work perception (occupational mental stress, intensity of concentration, job satisfaction, and job-related resignation) and psychosocial factors (anxiety, depression, self-control, social support, and marital status) were compared using multivariate techniques. Stepwise discriminate analysis was used to identify the best discriminating variables within the magnetic resonance image, work perception, and psychosocial categories in terms of the diagnostic accuracy to predict group membership (study [pain] or control [no pain] group). Results Matched controls had significantly more risk factors than a group of normal individuals. The present study has presented evidence that an age-, gender-, and occupational risk factors-matched group of asymptomatic patients shows a high incidence rate of disc herniations (76%). Although significantly less than the symptomatic group incidence of 96%, this represents a much higher prevalence rate than generally expected and reported in other studies of unmatched asymptomatic volunteers. Patients had more severe disc herniations (disc extrusions) than asymptomatic volunteers (35% vs. 13%). There was no significant differences regarding disc degeneration between both groups (96% vs. 85%). The only substantial morphologic difference between both groups was the presence of a neural compromise (83% vs. 22%), which was highly significant (P < 0.0001). There were significant differences between both groups regarding work perception (occupational mental stress, intensity of concentration, job satisfaction, and resignation; P<0.027) and psychosocial factors (anxiety, depression, self-control, marital status; P<0.0001). The best single predictor of a group membership was the extent of neural compromise. A combination of this factor with occupational mental stress, depression, and marital status was the best predictive model. With this model, the false-negative rate (potential overtreatment of disc morphology) was reduced by more than half compared with morphologic factors (nerve root compression) alone (22% vs. 11%). Conclusions. In an age-, sex-, and risk factormatched group of asymptomatic individuals, disc herniation had a substatially higher prevalence (76%) than previously reported in an unmatched group. Individuals with minor disc herniations (i.e., protrusion, contained discs) are at a very high risk that their magnetic resonance images are not a causal explanation of pain because a high rate of asymptomatic subjects (63%) had comparable morphologic findings. The only highly significant difference between the study group and control group regarding morphologic findings was the criteria of a nerve root compromise. Work perception and psychosocial factors were helpful in discriminating between symptomatic and asymptomatic disc herniations.

Young Investigator Award 2001 Winner : Risk Factors for Lumbar Disc Degeneration : A 5-Year Prospective MRI Study in Asymptomatic Individuals

Study Design. A longitudinal magnetic resonance imaging investigation of lumbar disc degeneration in asymptomatic individuals was conducted. Objective. To investigate risk factors for the development or deterioration of lumbar disc degeneration. Summary of Background Data. Numerous studies have explored the significance of certain risk factors for the development or progression of disc degeneration, but no comprehensive longitudinal magnetic resonance imaging–based study has been reported that simultaneously considers clinical, morphologic, physical, psychosocial, and occupational risk factors. Methods. In the 5-year follow-up evaluation of 41 asymptomatic individuals, the risk factors for the development of lumbar disc degeneration and its progression were investigated. All 41 individuals had a magnetic resonance imaging scan at baseline and at the minimum 5-year follow-up assessment using the same scanner and protocol. The magnetic resonance images were analyzed independently by two radiologists with regard to disc degeneration. Various predictor variables were assessed both at baseline and follow-up, with special emphasis on physical job characteristics, sports activities, and magnetic resonance image–based morphologic findings. Results. Of the 41 individuals, 17 (41%) exhibited a deterioration of the disc status. In 10 individuals, the progression of disc degeneration was one grade or more. Only a weak correlation existed between progressive disc degeneration and low back pain development during a 5-year follow-up period. Multiple logistic regression analysis demonstrated that the extent of disc herniation (odds ratio [OR], 12.63; confidence interval [CI], 1.24–128.49), the lack of sports activities (OR, 2.71; CI, 1.04–7.07), and night shift work (OR, 23.01; CI, 1.26–421.31) were significant predictors for disc degeneration during follow-up evaluation when control was used for the number of degenerated discs at baseline, gender, age, and body mass index. Conclusions. The results indicate that the extent of disc herniation, the lack of sports activities, and night shift work are significant risk factors for the development of lumbar disc degeneration and its progression.

Natural History of Individuals With Asymptomatic Disc Abnormalities in Magnetic Resonance Imaging : Predictors of Low Back Pain-Related Medical Consultation and Work Incapacity

Study Design. Prospective study on individuals with asymptomatic lumbar disc abnormalities detected in magnetic resonance imaging. Objectives. To determine the natural history of asymptomatic disc abnormalities in magnetic resonance imaging and to identify predictors of future low back pain–related medical consultation and work incapacity. Summary of Background Data. The natural history of individuals with asymptomatic disc herniations has not been well established, but the high rate of lumbar disc alterations recently detected in asymptomatic individuals by magnetic resonance imaging demands reconsideration of a pathomorphology-based explanation of low back pain and sciatica. Methods. Forty-six asymptomatic individuals who had a high rate of disc herniations (73%) were observed for an average of 5 years (range, 54–72 months). Four classes of variables (medical data including magnetic resonance imaging–identified disc abnormalities, general psychological factors, physical job characteristics, and psychosocial aspects of work) were assessed at baseline and follow-up. Results. Disc herniations and neural compromise did not significantly worsen at follow-up, whereas disc degeneration progressed in 17 individuals (41.5%). Minor episodes of low back pain occurred in 19 individuals (41.3%), 6 of whom had to seek medical treatment and 5 of whom had to stop work temporarily. The requirement for low back pain–related medical consultation was predicted with high accuracy by listlessness, job satisfaction, and working in shifts (P < 0.001). Work incapacity was best predicted by physical job characteristics, job disaffection, and working in shifts (P < 0.01). Conclusion. Physical job characteristics and psychological aspects of work were more powerful than magnetic resonance imaging–identified disc abnormalities in predicting the need for low back pain–related medical consultation and the resultant work incapacity. However,the conclusions are still preliminary, and replication of the findings in larger and more representative study samples is needed.

The impact of clinical, morphological, psychosocial and work-related factors on the outcome of lumbar discectomy

In a prospective controlled trial on 46 patients undergoing lumbar discectomy, three classes of variables (medical data including MRI-identified morphological abnormalities, general psychological factors and psychosocial aspects of work) were analyzed with regard to their predictive value for the outcome of lumbar disc surgery at 2 year follow-up. Multiple regression analyses were used to identify the best predictor variables of four different outcome measures (i.e. pain relief, reduction of disability in daily activities, return to work and surgical outcome). MRI-identified nerve root compromise and social support from the spouse were independent predictors of pain relief 2 years after surgery (R2 = 0.40, P < 0.01). Return to work 2 years after surgery was best predicted by depression and occupational mental stress (R2 = 0.36, P < 0.001). MRI-identified extent of herniation and depression were significant predictors of a good surgical outcome after lumbar discectomy (R2 = 0.61, P < 0.001). This study has demonstrated that the outcome of discectomy is critically dependent on which outcome variables are selected and that different sorts of predictor variables have a distinct influence on the various outcome variables. Obvious morphological alterations (i.e. disc extrusions, nerve root compromise) proved to be significant predictors of postoperative pain relief and improvement of disability in daily activities justifying a surgical treatment approach in these cases. The most important finding of this study was that return to work was not influenced by any clinical findings or MR-identified morphological alterations, but solely by psychological factors (i.e. depression) and psychological aspects of work (i.e. occupational mental stress).

Working conditions, well-being, and job-related attitudes among call centre agents

A comparison of 234 call centre agents with 572 workers in traditional jobs with long lasting training revealed lower job control and task complexity/variety and higher uncertainty among call agents. However, time pressure, concentration demands, and work interruptions were lower in call agents. Within the call agent sample, controlling for negative affectivity and other working conditions, job control predicted intention to quit, and job complexity/variety predicted job satisfaction and affective commitment. Social stressors and task-related stressors predicted uniquely indicators of well-being and job-related attitudes. Furthermore, data confirm the role of emotional dissonance as a stressor in its own right, as it explained variance in irritated reactions and psychosomatic complaints beyond other working conditions. Results indicate that strong division of labour may be a rather general phenomenon in call centres. Therefore, working conditions of call agents require a redesign by means of job enrichment or—better—organization development. Moreover, measures of social stressors and emotional dissonance should be integrated routinely into stress-related job analyses in service jobs.

Brief leadership instructions improve cardiopulmonary resuscitation in a high-fidelity simulation: A randomized controlled trial

Objective:The influence of teaching leadership on the performance of rescuers remains unknown. The aim of this study was to compare leadership instruction with a general technical instruction in a high-fidelity simulated cardiopulmonary resuscitation scenario. Design:Prospective, randomized, controlled superiority trial, Setting:Simulator Center of the University Hospital Basel in Switzerland. Subjects:Two-hundred thirty-seven volunteer medical students in teams of three. Intervention:During a baseline visit, the medical students participated in a video-taped simulated witnessed cardiac arrest. Participants were thereafter randomized to receive instructions focusing either on correct positions of arms and shoulders (technical instruction group) or on leadership and communication to enhance team coordination (leadership instruction group). A follow-up simulation was conducted after 4 mos. Measurements and Main Results:The primary outcome were the amount of hands-on time, defined as duration of uninterrupted cardiopulmonary resuscitation in the first 180 secs after the onset of the cardiac arrest (hands-on time). Secondary outcomes were time to start cardiopulmonary resuscitation, total leadership utterances, and technical skills. Outcomes were compared based on videotapes coded by two independent researchers. After a balanced performance at baseline, the leadership instruction group demonstrated a longer hands-on time (120 secs; interquartile range, 98–135 vs. 87 secs; interquartile range, 61–108; p < .001), a shorter median time to start cardiopulmonary resuscitation (44 secs; interquartile range, 32–62; vs. 67 secs; interquartile range, 43–79; p = .018), and had more leadership utterances (7; interquartile range, 4–10; vs. 5; interquartile range, 2–8; p = .02) in the follow-up visit. The rate of correct arm and shoulder positions was higher in teams with technical instruction (59%; 19 out of 32; vs. 23%; 7 out of 31; p = .003). Conclusions:Video-assisted leadership and technical instructions after a simulated cardiopulmonary resuscitation scenario showed sustained efficacy after a 4-mo duration. Leadership instructions were superior to technical instructions, with more leadership utterances and better overall cardiopulmonary resuscitation performance.

The double meaning of control: three-way interactions between internal resources, job control, and stressors at work.

The Job Demand-Control model postulates that job control attenuates the effects of job demands on health and well-being. Support for this interactive effect is rather weak. Conceivably, it holds only when there is a match between job control and individual characteristics that relate to exercising control options, such as locus of control, or self-efficacy. This three-way interaction was tested in a sample of 96 service employees, with affective strain and musculoskeletal pain as dependent variables. As hypothesized, job control attenuated the effects of stressors only for people with an internal locus of control. For people with an external locus of control, job control actually predicted poorer well-being and health as stressors increased. For self-efficacy, the corresponding three-way interaction was significant with regard to affective strain.

Teamwork and Leadership in Cardiopulmonary Resuscitation

Despite substantial efforts to make cardiopulmonary resuscitation (CPR) algorithms known to healthcare workers, the outcome of CPR has remained poor during the past decades. Resuscitation teams often deviate from algorithms of CPR. Emerging evidence suggests that in addition to technical skills of individual rescuers, human factors such as teamwork and leadership affect adherence to algorithms and hence the outcome of CPR. This review describes the state of the science linking team interactions to the performance of CPR. Because logistical barriers make controlled measurement of team interaction in the earliest moments of real-life resuscitations challenging, our review focuses mainly on high-fidelity human simulator studies. This technique allows in-depth investigation of complex human interactions using precise and reproducible methods. It also removes variability in the clinical parameters of resuscitation, thus letting researchers study human factors and team interactions without confounding by clinical variability from resuscitation to resuscitation. Research has shown that a prolonged process of team building and poor leadership behavior are associated with significant shortcomings in CPR. Teamwork and leadership training have been shown to improve subsequent team performance during resuscitation and have recently been included in guidelines for advanced life support courses. We propose that further studies on the effects of team interactions on performance of complex medical emergency interventions such as resuscitation are needed. Future efforts to better understand the influence of team factors (e.g., team member status, team hierarchy, handling of human errors), individual factors (e.g., sex differences, perceived stress), and external factors (e.g., equipment, algorithms, institutional characteristics) on team performance in resuscitation situations are critical to improve CPR performance and medical outcomes of patients.

Longitudinal validation of the Fear-Avoidance Beliefs Questionnaire (FABQ) in a Swiss-German sample of low back pain patients

Work and activity-specific fear-avoidance beliefs have been identified as important predictor variables in relation to the development of, and treatment outcome for, chronic low back pain. The objective of this study was to provide a cross-cultural German adaptation of the Fear-Avoidance Beliefs Questionnaire (FABQ) and to investigate its psychometric properties (reliability, validity) and predictive power in a sample of Swiss-German low back pain patients. Questionnaires from 388 operatively and non-operatively treated patients were administered before and 6 months after treatment to assess: socio-demographic data, disability (Roland and Morris), pain severity, fear-avoidance beliefs, depression (ZUNG) and heightened somatic awareness (MSPQ). Complete baseline and follow-up questionnaires were available from 255 participants. The corrected item-total correlations, coefficients of test-retest reliability and internal consistencies of the two scales of the questionnaire were highly satisfactory. In a confirmatory factor analysis (CFA), all items loaded on the appropriate factor with minor loadings on the other. Cross-sectional regression analysis with disability and work loss as the dependent variables yielded results that were highly comparable with those reported for the original version. Prognostic regression analysis replicated the findings for work loss. The cross-cultural German adaptation of the FABQ was very successful and yielded psychometric properties and predictive power of the scales similar to the original version. The inclusion of fear-avoidance beliefs as predictor variables in studies of low back pain is highly recommended, as they appear to have unique predictive power in analyses of disability and work loss.