Preventing sickness absenteeism among employees with common mental disorders or stress-related symptoms at work: Design of a cluster randomized controlled trial of a problem-solving based intervention versus care-as-usual conducted at the Occupational Health Services.

BACKGROUND: Common mental disorders (CMDs) are among the leading causes of sick leave in Sweden and other OECD countries. They result in suffering for the individual and considerable financial costs for the employer and for society at large. The occupational health service (OHS) can offer interventions in which both the individual and the work situation are taken into account. The aim of this paper is to describe the design of a study evaluating the effectiveness of an intervention given at the OHS to employees with CMDs or stress-related symptoms at work. In addition, intervention fidelity and its relation to the outcome will be assessed in a process analysis. METHODS: The study is designed as a cluster randomized trial in which the participating OHS consultants are randomized into either delivering the intervention or performing care as usual. Employees with CMDs or stress-related symptoms at work are recruited consecutively by the OHS consultants. The intervention aims to improve the match between the employee and the job situation. Interviews are held individually with the employee and the nearest supervisor, after which a joint meeting with both the employee and the supervisor takes place. A participatory approach is applied by which the supervisor and the employee are guided by the OHS consultant and encouraged to actively take part in problem solving concerning the work situation. Outcomes will be assessed at baseline and at six and 12 months. A long-term follow-up at 3 years will also be performed. The primary outcome is registered sickness absence during a 1-year period after study inclusion. Secondary outcomes are mental health and work ability. The intervention's cost effectiveness, compared to treatment as usual, both for society and for the employer will be evaluated. A process evaluation by both the OHS consultants and the employee will be carried out. DISCUSSION: The study includes analyses of the effectiveness of the intervention (clinical and economic) as well as an analysis of its implementation at the participating OHSs. Possible methodological challenges such as selection bias and risk of contamination between OHS consultants delivering the experimental condition and consultants giving usual care are discussed. TRIAL REGISTRATION: ClinicalTrials NCT02563743 Sep 28 2015.

Validity of the 12-item version of the General Health Questionnaire in detecting depression in the general population.

OBJECTIVES: The 12-item version of the General Health Questionnaire (GHQ-12) is frequently used to measure common mental disorder in public health surveys, but few population-based validations have been made. We validated the GHQ-12 against structured psychiatric interviews of depression using a population-based cohort in Stockholm, Sweden. METHODS: We used a population-based cohort of 484 individuals in Stockholm, Sweden (participation rate 62%). All completed the GHQ-12 and a semi-structured psychiatric interview. Last month DSM-III-R symptoms were used to classify major and minor depression. Three scoring methods for GHQ-12 were assessed, the Standard, Likert and Corrected method. Discriminatory ability was assessed with area under the receiver operating characteristic (ROC) curve. RESULTS: A total of 9.5% had a major or minor depression. The area under the ROC curve was for the Standard method 0.73 (0.65-0.82), the Likert method 0.80 (0.72-0.87) and the Corrected method 0.80 (0.73-0.87) when using major or minor depression as standard criterion. Adequate sensitivity and specificity for separating those with or without a depressive disorder was reached at ≥12 Likert scored points (80.4 and 69.6%) or ≥6 Corrected GHQ points (78.3 and 73.7%). Sensitivity and specificity was at ≥2 Standard scored points 67.4% and 74.2%. CONCLUSION: When scored using the Likert and Corrected methods, the GHQ-12 performed excellently. When scored using the Standard method, performance was acceptable in detecting depressive disorder in the general population. The GHQ-12 appears to be a good proxy for depressive disorder when used in public health surveys.

Effects of drop out in a longitudinal study of musculoskeletal disorders.

OBJECTIVES: The drop out rates in different longitudinal studies of musculoskeletal disorders range between 7% and 57%, and little is known about the characteristics of the subjects who dropped out. The aim was to analyse various consequences of drop out in a longitudinal study of musculoskeletal disorders and occupational risk factors during 1969-97. METHOD: Data about occupational conditions and health in 1969 and in 1993 were analysed. Differences between those who participated throughout (participants) and drop out subjects in these analyses formed the basis for recalculations of earlier reported analyses of associations between occupational conditions and low back pain. In the recalculation the data were weighted to compensate for the differences. RESULTS: More female and male drop out subjects than participants in 1993 had monotonous work, fewer women and more male drop out subjects had heavy lifting in 1969. In 1997, more female and male drop out subjects had had heavy lifting and low stimulation at work in 1993. At both occasions, there were differences between the drop out subjects and participants in occurrence of musculoskeletal disorders. The weighted analyses resulted in changes in risk ratio of 0.1-0.2. CONCLUSIONS: Differences in occupational conditions and health among participants and drop out subjects in a longitudinal study of musculoskeletal disorders and occupational risk factors during 1969-97 did not markedly influence the risk ratios.

Risk factors for neck and shoulder disorders: a nested case-control study covering a 24-year period.

BACKGROUND: In 1969 a population-based study was conducted in the Stockholm region. From the 2,579 randomly selected participants (18-65 years of age in 1969), the youngest subset were asked to participate in a reexamination in 1993. Information regarding working conditions, conditions outside work, and neck and shoulder disorders was collected retrospectively for the period 1970-1993. METHODS: Of 783 eligible subjects (42-59 years of age in 1993), 484 responded. Cases of neck/shoulder disorders were defined by past sick leave or medical attention or recent symptoms, depending on available information. For each case (n = 271) two controls were randomly selected, matched by age and gender. Variables regarding both physical and psychosocial conditions were included in the matched analyses. RESULTS: Among women mainly psychosocial factors and among men mainly physical factors were associated with neck/shoulder disorders. The only gender common risk indicator found was repetitive hand work (OR approximately 1.5). Interactive effects were also observed. CONCLUSIONS: The impact on neck/shoulder disorders from separate factors was moderate but combinations of physical and psychosocial factors, as well as of work-related and non-work-related factors, produced relative risks above 2.

The effects of a change in work organization upon the work environment and musculoskeletal symptoms among letter carriers.

An organizational change among 82 postal workers was studied with the aim of evaluating the effects on the work environment, work ability, and musculoskeletal complaints. The study was undertaken in 2 suburbs of Stockholm, Sweden. Psychological work demands were estimated to be reduced at the 1-year follow-up but physical work demands had changed very little. In an observation study in a subgroup of older workers, the risk of overexertion at work and musculoskeletal complaints was reduced. In spite of that, most of the older participants (>/=35 years) had unchanged or increased musculoskeletal symptoms. This shows the need for early preventive measures.

Physical work load between 1970 and 1993--did it change?

OBJECTIVES: This study investigates changes in self-reported and expert-evaluated physical work loads between 1970 and 1993 in relation to calendar year, birth cohort, and gender in an urban and suburban population sample (232 men and 252 women) born between 1935 and 1952. METHODS: A self-administered questionnaire was answered in 1993 concerning different aspects of physical work loads between 1970 and 1993. With the use of a classification matrix, the objective physical work load on different body regions was also assessed. RESULTS: Between 1970 and 1993 the fraction of subjects in blue-collar occupations and the physical work loads decreased among the men, but they both increased among the women. Physical work loads were, in general, higher among the men than among the women at younger ages (below 30 years), but less so at higher ages. Expert evaluations of the musculoskeletal load showed a pattern similar to that of self-reported work loads. CONCLUSIONS: The gender difference in work load development with age may have implications for the development of musculoskeletal disorders.

Physical and psychosocial factors related to low back pain during a 24-year period. A nested case-control analysis.

STUDY DESIGN: A retrospective nested case-control study. OBJECTIVES: To identify occupational factors related to low back pain, and to study how interactions between psychosocial and physical factors, and between work-related and leisure-related factors affect low back pain in women and men. SUMMARY OF BACKGROUND DATA: A cohort of 484 subjects drawn from the general population was examined in 1969 and 1993, with a focus on occupational working conditions and musculoskeletal disorders. METHODS: Information about the physical and psychosocial working conditions and low back pain during the period 1970 to 1993 was collected retrospectively. Odds ratios and confidence intervals were calculated for different potential risk factors. RESULTS: During the 24-year period, 46% of the subjects became patients with low back pain. Among women, heavy physical workload, sedentary work, smoking, and the combination of whole-body vibrations and low influence over work conditions were associated with an excess risk of low back pain. Among men, excess risk for low back pain was seen in heavy physical workload, sedentary work, high perceived load outside work, and the combination of poor social relations and overtime. CONCLUSIONS: Factors at work were seen to be risk indicators for low back pain among both genders. Low influence over work conditions among women and poor social relations at work among men, in combination with other factors, seem to be of high relevance for the occurrence of low back pain.

Physical capacity in relation to present and past physical load at work: a study of 484 men and women aged 41 to 58 years.

BACKGROUND: A negative association has previously been reported between long-lasting physically heavy work and some measures of physical capacity. This relationship was further investigated in a 24-year follow-up study of 484 middle-aged men and women from the general population. METHODS: A questionnaire was administered in 1993 concerning retrospective recall of physical work loads and physical training in the time span between 1970 and 1993. Laboratory tests performed in 1993 included tests of muscle function (maximal isometric strength and dynamic endurance) and aerobic power (submaximal ergometer test). RESULTS: Consistent with the hypothesis, but mainly among the women, associations between long-lasting physically heavy demands and low trunk flexion strength, squatting endurance, and aerobic power were observed. In contrast, low isometric hand grip strength and low weight lifting endurance were seldom seen among those with high physical work loads, indicating a possible maintaining or training effect on the hand/arm/shoulder muscle groups. CONCLUSIONS: Physically heavy work seems to have a different impact on different parts of the musculoskeletal system, an effect that is also different between men and women.

Evaluation of questionnaire-based information on previous physical work loads. Stockholm MUSIC 1 Study Group. Musculoskeletal Intervention Center.

OBJECTIVES: The principal aim of the present study was to evaluate questionnaire-based information on past physical work loads (6-year recall). METHODS: Effects of memory difficulties on reproducibility were evaluated for 82 subjects by comparing previously reported results on current work loads (test-retest procedure) with the same items recalled 6 years later. Validity was assessed by comparing self-reports in 1995, regarding work loads in 1989, with worksite measurements performed in 1989. RESULTS: Six-year reproducibility, calculated as weighted kappa coefficients (k(w)), varied between 0.36 and 0.86, with the highest values for proportion of the workday spent sitting and for perceived general exertion and the lowest values for trunk and neck flexion. The six-year reproducibility results were similar to previously reported test-retest results for these items; this finding indicates that memory difficulties was a minor problem. The validity of the questionnaire responses, expressed as rank correlations (r(s)) between the questionnaire responses and workplace measurements, varied between -0.16 and 0.78. The highest values were obtained for the items sitting and repetitive work, and the lowest and "unacceptable" values were for head rotation and neck flexion. Misclassification of exposure did not appear to be differential with regard to musculoskeletal symptom status, as judged by the calculated risk estimates. CONCLUSIONS: The validity of some of these self-administered questionnaire items appears sufficient for a crude assessment of physical work loads in the past in epidemiologic studies of the general population with predominantly low levels of exposure.

Risk factors for neck and upper limb disorders: results from 24 years of follow up.

OBJECTIVES: To investigate associations between different potential risk factors, related and not related to work, and disorders of the neck and upper extremities occurring up to 24 years later. METHODS: The study comprised 252 women and 232 men, Swedish citizens, 42-59 years of age and in a broad range of occupations. Information about potential risk factors was available from a former study conducted in 1969. Data on disorders of the neck, shoulder, and hand-wrist disorders were obtained retrospectively for the period 1970-93. RESULTS: Risk factors were found to differ between the sexes. Among women over-time work, high mental workload, and unsatisfactory leisure time were associated with disorders in the neck-shoulder region. Interaction was found between high mental workload and unsatisfactory leisure time. Neck symptoms earlier in life were associated with recurrent disorders. Hand and wrist disorders were associated mainly with physical demands at work. Among men blue collar work and a simultaneous presence of high mental workload and additional domestic workload predicted disorders in the neck-shoulder region. CONCLUSIONS: Factors related and not related to work were associated with disorders of the neck, shoulders, and hands and wrist up to 24 years later in life. These included factors related to working hours which previously have not been noted in this context. Interactions between risk factors both related and not related to work were commonly found.

Validity and reliability of self-reported retrospectively collected data on sick leave related to musculoskeletal diseases.

OBJECTIVES: The aim was to study the reliability and validity of retrospective data, collected by self-report, on sick leave related to musculoskeletal diseases. METHODS: The study groups consisted of 66 and 306 subjects, for the reliability and validity studies, respectively. They were all part of a wider study of risk factors for musculoskeletal disorders, the REBUS study, conducted in Stockholm in 1993. Reliability was tested using a test-retest design regarding self-reported sick leave related to musculoskeletal diseases in 1970-1993. The validity study comprised the period 1990-1994. Self-reported and registered sick-leave data related to musculoskeletal diseases were collected and analyzed regarding concordance. Data about current musculoskeletal disorders and different work-related conditions were collected and analyzed regarding possible effect- and exposure-dependent misclassification. RESULTS: The test-retest reliability study showed the percentage of agreement to be between 0.88 and 0.97, and the kappa values were between 0.73 and 0.93. The validity study of the concordance between the self-reported and registered data showed high agreement and specificity, but the sensitivity was sometimes lower. All the kappa values exceeded 0.50. No effect- or exposure-dependent misclassification was found. CONCLUSIONS: The validity of retrospectively collected self-reported sick-leave data was sufficient for use as a measure of musculoskeletal morbidity in the analyses of associations with work-related conditions. Because of the relatively low sensitivity, such data will underestimate the prevalence of sick leave and should not be used for surveys of morbidity.

Psychosocial and physical risk factors associated with low back pain: a 24 year follow up among women and men in a broad range of occupations.

OBJECTIVES: To investigate the relation between psychosocial and physical factors at work, as well as conditions during leisure time, and low back pain (LBP) over 24 years. METHODS: The study group consisted of 252 women and 232 men. From a previous study conducted in 1969, data on psychosocial and physical conditions and LBP were available. Data on LBP for 1971-93 were obtained retrospectively in 1993. RESULTS: The prevalence of LBP in 1969 among women and men were 34% and 24%, the cumulative incidences of LBP during 1970-92 were 38% and 43%, and the prevalences in 1993 of having had LBP during the past 12 months were 44% and 39%, respectively. Monotonous work and few or unsatisfactory social contacts outside work were risk factors for LBP in 1969 among women. LBP in 1969 and dissatisfaction with leisure time were risk factors among both sexes for LBP in 1970-92. LBP in 1969 was a risk factor for LBP in 1993 among women and dissatisfaction with leisure time a risk factor among men. Interactions between few or unsatisfactory social contacts outside work, as well as dissatisfaction with leisure time, and several factors related to work were found to increase the risk of LBP among both sexes during the studied periods. CONCLUSIONS: Conditions in leisure time exert a long term influence on LBP. In this study factors related to work had a long term effect only in interaction with leisure time factors.

Reproducibility of a questionnaire for assessment of present and past physical activities.

OBJECTIVE: The aim of this study was to evaluate the reproducibility of a self-administered questionnaire about present and past physical activities at work and during leisure time. METHODS AND DESIGN: The questionnaire, covering the period 1970-1993, comprised 12 questions on physical activities at work, and 12, with similar wording, for such activities in leisure time. There were also four questions on physical training. Two-week reproducibility (test-retest reliability) concerning the period 1970-1993 was analysed in a group of 44 subjects, and 1-year reproducibility, concerning current activities in 1993, was analysed in a second group of 123 subjects in relation to gender, age and low-back health. RESULTS: Test-retest reliability calculated as intraclass correlation coefficients (ri) for physical activities at work (ri 0.41-0.98) exceeded that for leisure time and physical training activities (ri 0.33-0.68). Calculated correlations did not differ markedly between past and present activities. No distinct influence of gender or low back health on 1-year reproducibility was found, in contrast to a slight tendency towards higher reproducibility among subjects of 50 years and older compared with younger subjects. CONCLUSIONS: Reproducibility of this questionnaire about physical activities at work showed no clear tendency to deteriorate regarding activities during the immediately preceding two decades. The questions about physical activities during leisure time have to be revised. Reliable retrospective information about physical activities in leisure time could perhaps not be collected by self-administered questionnaires and other methods, e.g. interview-based questionnaires, may be more suitable.

Physical work load, physical capacity and strain among elderly female aides in home-care service.

A study was undertaken to investigate physical work load, physical capacity, physical strain and perceived health among elderly aides in home-care service. A secondary aim was to compare the work load and strain between the two main types of home-care service available in Sweden today. Work tasks and their distribution among 20 elderly aides (aged 45-65 years), working in open home-care service (clients living in their original flats or houses) and at service apartment houses (clients living in private flats constructed for the elderly and handicapped with service functions) were observed during whole work days. Heart rate and number of steps taken were also measured continuously during the whole work day. Oxygen consumption and work postures for upper arm and back were measured during parts of the work day. The results showed that home-care work is characterised by long periods of standing and walking and that postures potentially harmful for the low back and shoulders occurred frequently. Average physiological strain measured as relative oxygen consumption and heart rate during the work day did not exceed present recommendations. Average physical work load and strain in open home-care service slightly exceeded those in service apartment houses because of more frequent cleaning and walking outdoors. Many aides in this study showed slightly reduced physical capacity, and musculoskeletal problems were common. Many elderly aides in home-care service are probably exposed at work to high risks of overexertion and impaired health as a result of high postural loads in combination with other known important factors, such as time stress and lack of equipment.

Volatile organic compounds, respirable dust, and personal factors related to prevalence and incidence of sick building syndrome in primary schools.

Possible relations between incidence and prevalence of sick building syndrome (SBS), indoor exposures, and personal factors were studied in a four year longitudinal study among personnel (n = 129) in six primary schools. The mean concentration of carbon dioxide was above the recommended value of 0.08 microliter/l (800 ppm) in all schools, indicating a poor outdoor air supply. Indoor concentration of volatile hydrocarbon (VOC) was enhanced at high room temperatures. Respirable dust, but not concentration of VOC was enhanced at lower ventilation rates and high air humidity. Chronic SBS was related to VOC, previous wall to wall carpeting in the schools, hyper-reactivity, and psychosocial factors. Incidence of new SBS was related to concentration of respirable dust, current smoking, and the psychosocial climate. Remission of hyperreactivity, decrease in sick leave owing to airway illness, removal of carpeting in the schools, and moving from new to old dwellings resulted in a decrease in SBS score. It is concluded that SBS is of multifactorial origin, related to a variety of factors and exposures. The total concentration of hydrocarbons is a simple and convenient measure of exposure, which also seems to be a predictor of chronic symptoms. Further investigations on the effect of temperature, ventilation, and air humidity on SBS should consider how these factors may influence the chemical composition of the air. Because poor air quality in schools could also affect the children, it may have implications for the state of health of a large proportion of the population.