Validity of a self-administered questionnaire for assessing physical work loads in a general population

Risk Factors for Surgical Treatment of Lumbar Degenerative Disc Disease in Middle-aged and Older Women: A Prospective Case-Control Study of 2370 Subjects

OBJECTIVE

Given the distinct physiological and societal traits between women and men, we propose that there are distinct risk factors for lumbar degenerative disc disease surgeries, including lumbar disc herniation (LDH) and lumbar spinal stenosis (LSS), in middle-aged and older populations. However, few studies have focused on middle-aged and older women. This study aims to identify these risk factors specifically in this population.

METHODS

In this case-control study, the study group comprised 1202 women aged ≥ 45 years who underwent operative treatment of lumbar degenerative disc disease (LDH, n = 825; LSS, n = 377), and the control group comprised 1168 women without lumbar disease who visited a health examination clinic during the same period. The study factors included demographics (age, body mass index [BMI], smoking, labor intensity, and genetic history), female-specific factors (menopausal status, number of deliveries, cesarean section, and simple hysterectomy), surgical history (number of abdominal surgeries, hip joint surgery, knee joint surgery, and thyroidectomy), and systemic diseases (hypercholesterolemia, hypertriglyceridemia, hyper-low-density lipoprotein cholesterolemia, hypertension, diabetes, cardiovascular disease, and cerebrovascular disease). Multivariate binary logistic regression analysis was used to calculate the odds ratio (OR) and 95% confidence interval (95% CI) of associated factors.

RESULTS

The risk factors for surgical treatment of LDH in middle-aged and older women included BMI (OR = 1.603), labor intensity (OR = 1.189), genetic history (OR = 2.212), number of deliveries (OR = 1.736), simple hysterectomy (OR = 2.511), hypertriglyceridemia (OR = 1.932), and hyper-low-density lipoprotein cholesterolemia (OR = 2.662). For surgical treatment of LSS, the risk factors were age (OR = 1.889), BMI (OR = 1.671), genetic history (OR = 2.134), number of deliveries (OR = 2.962), simple hysterectomy (OR = 1.968), knee joint surgery (OR = 2.527), hypertriglyceridemia (OR = 1.476), hyper-low-density lipoprotein cholesterolemia (OR = 2.413), and diabetes (OR = 1.643). Cerebrovascular disease was a protective factor against surgery for LDH (OR = 0.267).

CONCLUSIONS

BMI, genetic history, number of deliveries, simple hysterectomy, hypertriglyceridemia, and hyper-low-density lipoprotein cholesterolemia were independent risk factors for surgical treatment of both LDH and LSS in middle-aged and older women. Two disparities were found: labor intensity was a risk factor for LDH patients, and knee joint surgery and diabetes were risk factors for LSS patients.

Predisposition and Working Conditions for the Occurrence of Lumbar Syndrome in Medical Workers of the Clinical Center of Montenegro during the COVID-19 Pandemic

Background: Lumbar pain is a condition of discomfort in the lower back caused by numerous factors, lasting for short or longer periods of time. Healthcare professionals, regardless of the type of care they are engaged in, are at risk of lumbar pain. This is the first study that deals with the problem of lumbar syndrome in health workers in Montenegro. Methods: This cross-sectional study included full-time health workers employed in the Clinical Center of Montenegro who were involved in the treatment of COVID-19 patients during 2020 and 2021. The survey consisted of general questions for collecting socio-demographic and COVID-19 engagement data; the Modified Nordic questionnaire was used for the analysis of musculoskeletal symptoms, and the EQ-5D-questionnaire was used to measure the quality of life associated with health. Results: The one-year prevalence of lumbar pain was 68.1%. Factors associated with lumbar pain were as follows: a higher degree of physical inactivity (each subject with a higher degree of physical inactivity had a 24% higher chance of occurrence of lumbar pain); a higher degree of load and over-engagement during the COVID-19 pandemic (each subject with a higher degree of workload had a nearly 50% higher chance of occurrence of lumbar pain); duration of engagement during the COVID-19 pandemic (subjects engaged up to a month were 4 times more likely to develop lumbar pain, and subjects engaged for 1-3 months were 3.5 times more likely to develop lumbar pain compared to those who were not engaged in COVID-19 treatment). This study also confirms that lumbar syndrome affects the quality of life of health workers. Conclusions: Lumbar syndrome is highly prevalent among healthcare professionals in the Clinical Center of Montenegro, especially in the population of nurses, where evidence-based preventive measures are needed.

The Role of Perceived Job Exertion and Age as Moderators of the Relationship Between Gender and Upper Extremity Musculoskeletal Disability and Pain in Injured Workers

Purpose This cross-sectional study aimed to determine if age and perceived job exertion (PJE) moderate the effect of gender on upper extremity (UE) disorders in injured workers. Methods We sampled a consecutive cohort of patients attending a specialty clinic for injured workers with UE musculoskeletal problems. We measured UE disability and pain using the Quick Disability of the Arm, Shoulder, and Hand (QDASH). Participants reported their PJE on a Global Rating of Change scale ranging from 1 (minimal perceived exertion) to 15 (maximal perceived exertion). Linear regression was used to explore the effect of gender on QDASH. We probed the moderating role of age and PJE using floodlight regression and identified the Johnson-Neyman (JN) region of age and PJE, where the effect of gender on QDASH becomes significant at the 95% level. Results We analyzed 418 participants, of whom 44% were women. The effect of gender on QDASH was significant for women aged 49 or younger (JN-region border: Age = 48.5, effect = 4.4, SE = 2.2, p = 0.05). Women workers with UE disorders younger than 49 years old report higher levels of pain and disability than do men. After the age of 49 years, both men and women workers experience a similar worsening of UE pain and disability with increasing age. Pain and disability increase with increased perceived job demands similarly for both men and women workers. Conclusions Women younger than 49 years had higher levels of UE pain and disorders than men. Both men and women workers reported higher UE disability with an increase in their PJE.

Reasons for presenteeism in different occupational branches in Sweden: a population based cross-sectional study

Objective

To compare the prevalence and reasons for presenteeism in occupations in three branches defined as employees handling people, handling things or handling symbols.

Method

A cross-sectional population-based cohort study was conducted. The study group was drawn from a representative sample (n = 6230) aged 16–64, who had been interviewed in 2015 or in 2017 for the Swedish Work Environment Surveys (SWES). The odds ratios (ORs) stratified by occupational category for reasons of presenteeism, with 95% confidence intervals (CI), were estimated using binomial multiple logistic regression analysis.

Results

The study showed that presenteeism was more common among employees handling people (74%), when compared to employees handling things (65%) or handling symbols (70%). The most common reason for presenteeism among employees handling people was “I do not want to burden my colleagues”, while “Because nobody else can carry out my responsibilities” was most common in the other two categories. After control for socio-demography, work environments and health, the differences in reasons mostly remained significant between the three occupational categories.

Conclusion

The differences between occupational categories are important for prevalence and reasons for presenteeism. As presenteeism affects the future health of employees and the productivity of the work unit, attempts to reduce presenteeism may be important. Because the reasons vary between occupations, customized preventive measures should be applied in different occupational settings. Among employees handling people, covering up for absence in work team is relevant, while among employees handling symbols and handling things the corresponding focus could be on shared responsibilities for specific tasks.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00420-021-01701-2.

Agreement between observed and interview-based exposure to ergonomics factors for the upper extremities in employees of a package sorting plant

Aim of the study was to estimate agreement between observational and interview-based exposure to ergonomic factors at work. Thirty-two male workers employed in a logistics hub were interviewed through the OCRA check-list on exposure to ergonomic factors in one of six work tasks. Observations of workers in each work task, based on the same OCRA check-list, were used to assess exposure in that task. Agreement between observed and interview-based scores of the check-list OCRA index, as well as of frequency and posture, was estimated both at individual and task group level through the Intraclass Correlation Coefficient (ICC). At work task level, high concordance was found between observed and interview-based scores for all the exposures examined, while at the individual level agreement was moderate. These results suggest that exposure assessment through interviews based on the OCRA check-list is a valid method, which could be used as a workstation screening tool. Practitioner summary: The study aimed to evaluate agreement between observational and interview-based exposure to ergonomic factors at work, assessed through the OCRA check-list on 32 male workers. Agreement was found at least moderate, suggesting that interview-based exposure assessed through the OCRA check-list could be used as a proxy of observations for workstation screening. Abbreviations: ART: assessment of repetitive tasks; CI: confidence intervals; EAWS: European assembly worksheet; ICC: intraclass correlation coefficient; ISO: International Standards Organization; OCRA: occupational repetitive actions; ULRA: upper limb risk assessment; WUEMSDs: work-related upper extremity musculoskeletal disorders.

Risk Factors for Recurrent L4-5 Disc Herniation After Percutaneous Endoscopic Transforaminal Discectomy: A Retrospective Analysis of 654 Cases

Background

Percutaneous endoscopic lumbar discectomy (PELD) is an increasingly applied minimally invasive procedure that has several advantages in the treatment of lumbar disc herniation (LDH). However, recurrent LDH (rLDH) has become a concerning postoperative complication. It remains difficult to establish a consensus and draw reliable conclusions regarding the risk factors for rLDH.

Purpose

This retrospective study aimed to investigate the risk factors associated with rLDH at the L4-5 level after percutaneous endoscopic transforaminal discectomy (PETD).

Methods

A total of 654 patients who underwent the PETD procedure at the L4-5 level from October 2013 to January 2020 were divided into a recurrence (R) group (n=46) and a nonrecurrence (N) group (n=608). Demographic and clinical data and imaging parameters were collected and analyzed using univariate and multiple regression analyses.

Results

The current study found a 7% rate of rLDH at the L4/5 level after successful PETD. Univariate analysis showed that older age, high BMI, diabetes mellitus history, smoking, large physical load intensity, moderate disc degeneration, small muscle-disc ratio (M/D), more fat infiltration, large sagittal range of motion (sROM), scoliosis, small disc height index (DHI), small intervertebral space angle (ISA), and small lumbar lordosis (LL) were potential risk factors (P < 0.10) for LDH recurrence after PETD at the L4-5 level. Multivariate analysis suggested that high BMI, large physical load intensity, moderate disc degeneration, small M/D, more fat infiltration, large sROM, small ISA, and small LL were independent significant risk factors for recurrence of LDH after PETD.

Conclusion

Consideration of disc degeneration, M/D, fat infiltration of the paravertebral muscles, sROM, ISA, LL, BMI, and physical load intensity prior to surgical intervention may contribute to the prevention of rLDH following PETD and lead to a more satisfactory operative outcome and the development of a reasonable rehabilitation program after discharge.

The test-retest reliability of the Military Physical Loading Questionnaire (MPLQ)

INTRODUCTION

Despite the high prevalence of musculoskeletal injuries, there is a shortage of data quantifying the risk factors attributable to cumulative occupational demands among UK Military personnel. We developed a new comprehensive questionnaire that examines occupational and operational physical loading during military service. The aim of this study was to examine the test-retest reliability of the Military Physical Loading Questionnaire (MPLQ).

METHODS

Intraclass correlation coefficients (ICC) were used to evaluate the test-retest reliability (4-week interval) of the MPLQ on 18 occupational and 18 operational items in 50 male (mean age: 36 years; SD ±7.9) UK military personnel. A stratified analysis based on duration of Service (0-10 years, 11-20 years and ≥21 years) was conducted to assess whether stability of task items was dependent on participant length of recall. Internal consistency was assessed by Cronbach's alpha (α) coefficients.

RESULTS

Reliability of individual operational items ranged from fair to almost perfect agreement (ICC range: 0.37-0.89; α range: 0.53-0.94) with most items demonstrating moderate to substantial reliability. Overall scores related to occupational items showed substantial to almost perfect agreement between administrations (ICC range: 0.73-0.94; α range: 0.84-0.96). Stratifying by duration of Service showed similar within group reliability to the entire sample and no pattern of decreasing or increasing reliability with length of recall period was observed.

CONCLUSIONS

It is essential that data used in planning UK military policy and health services are as accurate as possible. This study provides preliminary support for the MPLQ as a reliable self-report instrument for assessing the cumulative lifelong effects of occupational loading in UK military personnel. Further validation studies using larger and more demographically diverse military populations will support its interpretation in future epidemiological research.

Healthy lifestyle behaviour and risk of long-duration troublesome neck pain among men and women with occasional neck pain: results from the Stockholm public health cohort

OBJECTIVES

The effect of a healthy lifestyle on the prognosis of neck pain is unknown. This study aimed to investigate if a healthy lifestyle behaviour influences the risk of long-duration troublesome neck pain among men and women with occasional neck pain.

DESIGN

Longitudinal cohort study.

SETTINGS

General population, and a subsample of the working population, in Stockholm County, Sweden.

PARTICIPANTS

This study involved 5342 men and 7298 women, age 18 to 84, from the Stockholm Public Health Cohort, reporting occasional neck pain at baseline in 2006.

MEASURES

Baseline information about leisure physical activity, smoking, alcohol consumption and consumption of fruits and vegetables were dichotomised into recommendations for healthy/not healthy behaviour. The exposure, a healthy lifestyle behaviour, was categorised into four levels according to the number of healthy behaviours (HB) met. Generalised linear models were applied to assess the exposure on the outcome long-duration troublesome neck pain (activity-limiting neck pain ≥2 days/week during the past 6 months), at follow-up in 2010.

RESULTS

The adjusted risk of long-duration troublesome neck pain decreased with increasing adherence to a healthy lifestyle behaviour among both men and women (trend test: p<0.05). Compared with the reference category, none or one HB, the risk decreased by 24% (risk ratio 0.76, 95% CI 0.58 to 0.98) among men and by 34% (0.66, 0.54 to 0.81) among women, with three or four HBs. The same comparison showed an absolute reduction of the outcome by 3% in men (risk difference -0.03, 95% CI -0.05 to -0.01) and 5% in women (-0.05,-0.08 to -0.03). Similar results were found in the working population subsample.

CONCLUSION

Adhering to a healthy lifestyle behaviour decreased the risk of long-duration troublesome neck pain among men and women with occasional neck pain. The results add to previous research and supports the importance of promoting a healthy lifestyle behaviour.

Predictive models for short-term and long-term improvement in women under physiotherapy for chronic disabling neck pain: a longitudinal cohort study

OBJECTIVES

To develop predictive models for short-term and long-term clinically important improvement in women with non-specific chronic disabling neck pain during the clinical course of physiotherapy.

DESIGN

Longitudinal cohort study based on data from a randomised controlled trial evaluating short-term and long-term effects on sensorimotor function over 11 weeks of physiotherapy.

PARTICIPANTS AND SETTINGS

Eighty-nine women aged 31-65 years with non-specific chronic disabling neck pain from Gävle, Sweden.

MEASURES

The outcome, clinically important improvement, was measured with the Patient Global Impression of Change Scale (PGICS) and the Neck Disability Index (NDI), assessed by self-administered questionnaires at 3, 9 and 15 months from the start of the interventions (baseline). Twelve baseline prognostic factors were considered in the analyses. The predictive models were built using random-effects logistic regression. The predictive ability of the models was measured by the area under the receiver operating characteristic curve (AUC). Internal validity was assessed with cross-validation using the bootstrap resampling technique.

RESULTS

Factors included in the final PGICS model were neck disability and age, and in the NDI model, neck disability, depression and catastrophising. In both models, the odds for short-term and long-term improvement increased with higher baseline neck disability, while the odds decreased with increasing age (PGICS model), and with increasing level of depression (NDI model). In the NDI model, higher baseline levels of catastrophising indicated increased odds for short-term improvement and decreased odds for long-term improvement. Both models showed acceptable predictive validity with an AUC of 0.64 (95% CI 0.55 to 0.73) and 0.67 (95% CI 0.59 to 0.75), respectively.

CONCLUSION

Age, neck disability and psychological factors seem to be important predictors of improvement, and may inform clinical decisions about physiotherapy in women with chronic neck pain. Before using the developed predictive models in clinical practice, however, they should be validated in other populations and tested in clinical settings.

Prevalence and factors associated with low back pain among health care workers in southwestern Saudi Arabia

BACKGROUND

The purpose was to measure the prevalence and related risk factors of low back pain (LBP) among health care workers (HCWs) at different levels of health care in southwestern Saudi Arabia.

METHODS

A cross-sectional study using a self-administered questionnaire was conducted among HCWs providing primary, secondary and tertiary health care services in the Aseer region, southwestern Saudi Arabia. The questionnaire collected data regarding having LBP in the past 12 months, socio-demographics, work conditions and history of chronic diseases, regular physical exercise and overexertional back trauma. Univariate and multivariable logistic regression analyses were performed.

RESULTS

Out of 740 participants, the overall prevalence of LBP in the past 12 months amounted to73.9% (95% CI: 70.7-77.0). The prevalence of LBP with neurological symptoms reached 50.0%. The prevalence of LBP necessitating medications and or physiotherapy was 40.5%, while the prevalence of LBP requiring medical consultation was 20%. Using multivariable logistic regression, the following risk factors were identified: working in secondary and tertiary hospitals (aOR = 1.32, 95% CI:1.01-1.76), increased BMI (aOR = 1.10, 95% CI:1.01-3.65), and positive history of overexertional back trauma (aOR = 11.52, 95% CI:4.14-32.08). On the other hand, practising regular physical exercise was a significant protective factor (aOR = 0.61, 95% CI: 0.42-0.89).

CONCLUSIONS

LBP is a common problem among HCWs. Many preventable risk factors have been identified, including exertional back trauma, increased BMI and lack of regular physical exercise. Occupational health and safety programmes to build ergonomically safe working conditions and encourage regular physical exercise are needed.

[Measuring work-related physical demand: factorial structure and reliability of items on posture, handling of loads and repetitiveness]

This study sought to analyze the dimensionality of a set of items that measure work-related physical demand, their internal consistency and their test-retest reliability. We carried out an exploratory factorial analysis of ten physical demand items in two populations, totaling 1,070 workers from the footwear industry and from urban cleaning, using weighted least squares means and adjusted variance with Promax oblique rotation. We measure internal consistency using Cronbach's alpha. The test-retest used a subsample of 121 workers, using quadratic weighted kappa. We identified two dimensions in urban cleaning and three in the footwear industry: (1) dynamic work with anomalous postures; (2) work that requires handling material; and (3) work that demands repetitive motions. Reliability was excellent for upright work posture, good for walking, moderate for lifting loads, squatting, rotated trunk and only regular for repetitive motions and arms above shoulders. The dimensions we identified through factorial analysis are compatible with the physical demands of urban cleaning and the footwear industry and, in general, showed good internal consistency. The 10 items' reliability was compatible with the literature, showing excellent to good reliability for general posture, moderate for specific body segment posture and regular for repetitiveness. Results reveal the specificity of each occupational group, which suggests a dimensionality of physical demand items, supporting their use for measuring physical exposure.

Can a bothersome course of pelvic pain from mid-pregnancy to birth be predicted? A Norwegian prospective longitudinal SMS-Track study

OBJECTIVE

To explore if pregnant women with pelvic girdle pain (PGP), subgrouped following the results from two clinical tests with high validity and reliability, differ in demographic characteristics and weekly amount of days with bothersome symptoms through the second half of pregnancy.

DESIGN

A prospective longitudinal cohort study.

PARTICIPANTS

Pregnant women with pelvic and lumbopelvic pain due for their second-trimester routine ultrasound examination.

SETTING

Obstetric outpatient clinic at Stavanger University Hospital, Norway.

METHODS

Women reporting pelvic and lumbopelvic pain completed a questionnaire on demographic and clinical features. They were clinically examined following a test procedure recommended in the European guidelines for the diagnosis and treatment of PGP. Women without pain symptoms completed a questionnaire on demographic data. All women were followed weekly through an SMS-Track survey until delivery.

PRIMARY AND SECONDARY OUTCOME MEASURES

The outcome measures were the results from clinical diagnostic tests for PGP and the number of days per week with bothersome pelvic pain.

RESULTS

503 women participated. 42% (212/503) reported pain in the lumbopelvic region and 39% (196/503) fulfilled the criteria for a probable PGP diagnosis. 27% (137/503) reported both the posterior pelvic pain provocation (P4) and the active straight leg raise (ASLR) tests positive at baseline in week 18, revealing 7.55 (95% CI 5.54 to 10.29) times higher mean number of days with bothersome pelvic pain compared with women with both tests negative. They presented the highest scores for workload, depressed mood, pain level, body mass index, Oswestry Disability Index and the number of previous pregnancies. Exercising regularly before and during pregnancy was more common in women with negative tests.

CONCLUSION

If both P4 and ASLR tests were positive mid-pregnancy, a persistent bothersome pelvic pain of more than 5 days per week throughout the remainder of pregnancy could be predicted. Increased individual control over work situation and an active lifestyle, including regular exercise before and during pregnancy, may serve as a PGP prophylactic.

Effects of psychosocial work factors and psychological distress on self-assessed work ability: A 7-year follow-up in a general working population

BACKGROUND

Toinvestigate the effects of psychosocial work factors (PWF) and psychological distress (PD) on self-assessed work ability.

METHODS

This follow-up study included 7,810 individuals (55%women) with good work ability at baseline. PWFandPD (measured by GHQ-12) were assessed at baseline and work ability at 7-year follow-up. Effects of PWF and PD on work ability were analyzed by logistic regression, odds ratios (OR) with 95% CI, and by mediation analysisusing 4-way decomposition.

RESULTS

Low support was associated with poor work ability for both women and men (OR 1.78 and 1.89). For men, also low skill discretion was associated with poor work ability (OR 2.07). For both women and men, PD was associated with poor work ability (OR 3.41 and 1.84). PD did not act as an intermediate variablein the association between PWF and work ability.

CONCLUSION

Strategies for sustainable work ability should focus on both working conditions and health factors. Am. J. Ind. Med. 60:121-130, 2017. © 2016 Wiley Periodicals, Inc.

Development and validation of a prediction model for long-term sickness absence based on occupational health survey variables

PURPOSE

The purpose of this study is to develop and validate a prediction model for identifying employees at increased risk of long-term sickness absence (LTSA), by using variables commonly measured in occupational health surveys.

MATERIALS AND METHODS

Based on the literature, 15 predictor variables were retrieved from the DAnish National working Environment Survey (DANES) and included in a model predicting incident LTSA (≥4 consecutive weeks) during 1-year follow-up in a sample of 4000 DANES participants. The 15-predictor model was reduced by backward stepwise statistical techniques and then validated in a sample of 2524 DANES participants, not included in the development sample. Identification of employees at increased LTSA risk was investigated by receiver operating characteristic (ROC) analysis; the area-under-the-ROC-curve (AUC) reflected discrimination between employees with and without LTSA during follow-up.

RESULTS

The 15-predictor model was reduced to a 9-predictor model including age, gender, education, self-rated health, mental health, prior LTSA, work ability, emotional job demands, and recognition by the management. Discrimination by the 9-predictor model was significant (AUC = 0.68; 95% CI 0.61-0.76), but not practically useful.

CONCLUSIONS

A prediction model based on occupational health survey variables identified employees with an increased LTSA risk, but should be further developed into a practically useful tool to predict the risk of LTSA in the general working population. Implications for rehabilitation Long-term sickness absence risk predictions would enable healthcare providers to refer high-risk employees to rehabilitation programs aimed at preventing or reducing work disability. A prediction model based on health survey variables discriminates between employees at high and low risk of long-term sickness absence, but discrimination was not practically useful. Health survey variables provide insufficient information to determine long-term sickness absence risk profiles. There is a need for new variables, based on the knowledge and experience of rehabilitation professionals, to improve long-term sickness absence risk profiles.

The Association Between Self-Assessed Future Work Ability and Long-Term Sickness Absence, Disability Pension and Unemployment in a General Working Population: A 7-Year Follow-Up Study

Purpose Work ability is commonly measured with self-assessments, in the form of indices or single items. The validity of these assessments lies in their predictive ability. Prospective studies have reported associations between work ability and sickness absence and disability pension, but few examined why these associations exist. Several correlates of work ability have been reported, but their mechanistic role is largely unknown. This study aims to investigate to what extent individual's own prognosis of work ability predicts labor market participation and whether this was due to individual characteristics and/or working conditions. Methods Self-assessed prognosis of work ability, 2 years from "now," in the Stockholm Public Health Questionnaire (2002-2003) was linked to national registers on sickness absence, disability pension and unemployment up to year 2010. Effects were studied with Cox regression models. Results Of a total of 12,064 individuals 1466 reported poor work ability. There were 299 cases of disability pension, 1466 long-term sickness absence cases and 765 long-term unemployed during follow-up. Poor work ability increased the risk of long-term sickness absence (HR 2.25, CI 95 % 1.97-2.56), disability pension (HR 5.19, CI 95 % 4.07-6.62), and long-term unemployment (HR 2.18, CI 95 % 1.83-2.60). These associations were partially explained by baseline health conditions, physical and (less strongly) psychosocial aspects of working conditions. Conclusions Self-assessed poor ability predicted future long-term sickness absence, disability pension and long-term unemployment. Self-assessed poor work ability seems to be an indicator of future labor market exclusion of different kinds, and can be used in public health monitoring.

The impact of work related physical activity and leisure physical activity on the risk and prognosis of neck pain - a population based cohort study on workers

BACKGROUND

The effect of physical activity on risk and prognosis for neck pain has been studied earlier with inconclusive results. There is a need for large prospective studies on the subject. The aim of this study was to investigate if work related physical activity and physical activity during leisure time are of importance for the risk and prognosis of neck pain in men and women.

METHODS

We used the Stockholm Public Health Cohort and formed two sub-cohorts of the working population based on data from 2002. Cohort I (risk cohort) included persons without neck pain (n = 4681), and cohort II (prognostic cohort) included persons with occasional neck pain (n = 6820) during the previous six months. Both cohorts were assessed for the outcome long duration troublesome neck pain (LDNP) in 2007. The exposures and potential confounders were assessed through a questionnaire in 2002. The question regarding work related physical activity over the past 12 months had five answering categories ranging from "sedentary" to"heavy". The question regarding leisure physical activity for the past 12 months had five answering categories ranging from "sedentary" to "regular physical activity". LDNP in 2007 was defined as having had troublesome neck pain lasting ≥ 3 consecutive months during the previous five years. Associations between work related physical activity and LDNP, as well as leisure physical activity and LDNP, were investigated by multivariable logistic regression, considering potential confounding factors.

RESULTS

In cohort I (risk cohort) we found an association between leisure physical activity and LDNP. In cohort II (prognostic cohort) we found no association between the exposures and the outcome.

CONCLUSION

The results suggest that leisure physical activity has a protective effect on the risk of developing LDNP in a population free from neck pain. It did not, however, affect the prognosis of occasional neck pain. Neither the risk nor the prognosis of neck pain was affected by work related physical activity in this study.

The effect of massage therapy and/or exercise therapy on subacute or long-lasting neck pain--the Stockholm neck trial (STONE): study protocol for a randomized controlled trial

BACKGROUND

Neck pain is a major health problem in populations worldwide and an economic burden in modern societies due to its high prevalence and costs in terms of health care expenditures and lost productivity. Massage and exercise therapy are widely used management options for neck pain. However, there is a lack of scientific evidence regarding their effectiveness for subacute and long-lasting neck pain. This study protocol describes a randomized controlled trial aiming to determine the effect of massage and/or exercise therapy on subacute and long-lasting neck pain over the course of 1 year.

METHODS/DESIGN

A randomized controlled trial in which at least 600 study participants with subacute or long-lasting nonspecific neck pain will be recruited and randomly allocated to one of four treatment arms: massage therapy (A), exercise therapy (B), exercise therapy plus massage therapy (C) and advice to stay active (D). The study has an E-health approach, and study participants are being recruited through advertising with a mix of traditional and online marketing channels. Web-based self-report questionnaires measure the main outcomes at 7, 12, 26 and 52 weeks after inclusion. The primary outcomes are a clinically important improvement in pain intensity and pain-related disability at follow-up, measured with a modified version of the Chronic Pain Questionnaire (CPQ). The secondary outcomes are global improvement, health-related quality of life (EQ-5D), sick leave, drug consumption and healthcare utilization. Adverse events are measured by questionnaires at return visits to the clinic, and automated text messages (SMSes) survey neck pain intensity and pain-related disability every week over one year.

DISCUSSION

The results of this study will provide clinicians and stakeholders much needed knowledge to plan medical care for subacute and long-lasting neck pain disorders.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN01453590. Date of registration: 3 July 2014.

Influence of musculoskeletal pain on workers' ergonomic risk-factor assessments

This study compares the ergonomic risk-factor assessments of workers with and without musculoskeletal pain. A questionnaire on the musculoskeletal pain experienced in various body regions during the 12 months and seven days preceding the data collection was administered to 473 workers from three industrial sectors. The Ergonomic Workplace Analysis method, developed by the Finnish Institute of Occupational Health (FIOH), was then used by the workers and an ergonomics expert to assess the workstations. The ergonomic quality of the workstations and the need for change were also assessed by the expert and the workers at the workstation, using visual analog scales (VAS). Results show that the workers in this study were exposed to significant musculoskeletal disorder (MSD) risk factors, according to the FIOH assessment and the high percentages of reported pain. The results also show that those who reported pain in the seven days prior to the assessment evaluated their workstations more negatively than subjects who reported no pain, while the expert found no difference between the two groups' exposure to MSD risk factors.

Interaction between physical and psychosocial risk factors on the presence of neck/shoulder symptoms and its consequences

This study aimed to quantify the interaction between physical and psychosocial factors on the presence of neck/shoulder symptoms (NSS) and its consequences (reduced activities and absenteeism) among 1294 coal mining workers in Indonesia. A self-administered questionnaire was used to obtain information on current workplace exposure and NSS and its consequences. Participants were grouped into one of four combination exposure groups: low physical and low psychosocial (as the reference group); low physical and high psychosocial; high physical and low psychosocial, and high physical and high psychosocial (HPhyHPsy). The attributable proportion (AP) due to interaction between both factors was examined. Individuals in the HPhyHPsy group were most likely to report NSS [odds ratio (OR) 4.83, 95% confidence interval (CI) 2.43-9.58], reduced activities (OR 3.90, 95% CI 2.36-6.43), and absenteeism (OR 3.91, 95% CI 2.11-7.25). This study has shown an interaction between physical and psychosocial factors that increases the OR of NSS (AP 0.49, 95% CI 0.08-0.89). Practitioner Summary: Although physical and psychosocial factors are known to be predictors for NSS, little is known about their interaction. Self-reported questionnaire was used to obtain information about physical and psychosocial factors at work. This study found an interaction between the physical and psychosocial risk factors that increases the odds ratio of NSS.

Interaction between physical and psychosocial work risk factors for low back symptoms and its consequences amongst Indonesian coal mining workers

This study assessed the interaction between physical and psychosocial factors for low back symptoms (LBS) and its consequences (reduced activities and absenteeism) in a developing country. A sample of 1294 Indonesian coal mining workers reported occupational exposures, LBS and its consequences using a self-administered questionnaire. Respondents were placed into one of four combination exposure groups: high physical and high psychosocial (HPhyHPsy); high physical and low psychosocial (HPhyLPsy); low physical and high psychosocial (LPhyHPsy), and; low physical and low psychosocial (LPhyLPsy). The attributable proportion due to interaction between physical and psychosocial factors was examined. Individuals in the HPhyHPsy group were most likely to report LBS (OR 5.42, 95% CI 3.30-8.89), reduced activities (OR 4.89, 95% CI 3.09-7.74), and absenteeism (OR 4.96, 95% CI 3.05-8.06). Interactions between physical and psychosocial factors were present for LBS, reduced activities, and absenteeism; although for LBS and absenteeism the interactions were not significant. Current smokers were more likely to report LBS consequences. Permanent employment and night shift work increased the odds of LBS and its consequences. We conclude that interventions aimed at reducing LBS and its consequences should address both physical and psychosocial factors, with a focus on smokers, permanent employment and night shift work.

Associations between health and combinations of sickness presence and absence

BACKGROUND

The association between sickness presence (SP), sickness absence (SA) and health is not well known although research on these phenomena has grown in recent years.

AIMS

To identify the health outcomes of different combinations of self-reported SP and SA while controlling for background and work-related factors.

METHODS

The study group was a representative three-wave sample of 1886 employed individuals from the Swedish Working Life Cohort, gathered in 2004-2006. Block-wise multiple logistic regression analyses were conducted for combinations of self-reported SP and SA, using controls for background, work-related and previous health factors.

RESULTS

The crude odds ratios showed that health and mental well-being were most negatively affected in the group with high SP and SA in the preceding year. When differences in individual background, health and work-related factors were controlled for, distinct significant odds ratios remained. The odds ratios for negative health outcomes were between 1.49 (95% CI: 1.02-2.18) and 2.64 (95% CI: 1.81-3.85) higher among those with both high SP and high SA than those with both low SP and low SA. However, the study also indicated that individuals with high SP and low SA showed the highest odds ratios for poor mental well-being.

CONCLUSIONS

The results showed that combinations of frequent self-rated SP and SA are related to negative values in the four measured aspects of self-reported health 1 year later. Occupational medicine practitioners should therefore be concerned particularly with employees who report frequently occurring SP and SA.

Joint laxity negatively correlates with lumbar disc degeneration in young adults

STUDY DESIGN

Cross-sectional study of preselected cohort of patients with neck pain.

OBJECTIVE

To determine the association between joint laxity and lumbar disc degeneration in young adults.

SUMMARY OF BACKGROUND DATA

Joint laxity is known to be closely related with orthopedic injuries and disease; however, studies about the relationship between spinal disorder and joint laxity are lacking.

METHODS

Patients aged 30 to 40 years, seen at the outpatient clinic of our hospital for the evaluation of neck pain, who had magnetic resonance imaging of the cervical spine with routine inclusion of T2-weighted sagittal plane of the whole spine were included in the study. The Beighton and Horan criteria was used for the assessment of joint laxity. Logistic regression analysis was performed to estimate the odds ratio for lumbar disc degeneration in patients with joint laxity, and other variables including age, sex, body mass index, physical workload, neck pain (visual analogue scale score), and related disability (neck disability index score), and sagittal alignment.

RESULTS

A total of 101 patients were enrolled in the study: 34 patients with joint laxity and 67 patients without joint laxity. There were no differences in age, body mass index, physical workload, neck pain (visual analogue scale score), and neck disability index score between the 2 groups, but there was a significant difference in sex ratio (P < 0.001). Patients with joint laxity showed increased lumbar lordosis (P = 0.004) and increased sacral slope (P = 0.003) but without significant difference in pelvic incidence (P = 0.084). In univariate analysis, presence of joint laxity (Beighton score ≥4) as well as positive results of thumb (P = 0.016) and elbow (P = 0.047) tests were significantly associated with decreased risk for lumbar disc degeneration. Presence of joint laxity remained significant after multivariate adjustment for sex and lumbar lordosis (odds ratio = 0.373, P = 0.040).

CONCLUSION

Increased joint laxity was closely associated with lower prevalence of lumbar disc degeneration in young adults, and the increased lumbar lordosis associated with joint laxity might explain the decreased risk of lumbar disc degeneration.

LEVEL OF EVIDENCE

2.

The influence of self-reported leisure time physical activity and the body mass index on recovery from persistent back pain among men and women: a population-based cohort study

BACKGROUND

There is limited knowledge about leisure time physical activity and the body mass index (BMI) as prognostic factors for recovery from persistent back pain. The aim of this study was to assess the influence of leisure time physical activity and BMI on recovery from persistent back pain among men and women in a general population.

METHODS

The study population (n=1836) in this longitudinal cohort study consisted of participants reporting persistent back pain in the baseline questionnaire in 2002-2003. Data on leisure time physical activity, BMI and potential confounders were also collected at baseline. Information on recovery from persistent back pain (no back pain periods ≥ 7 days during the last 5 years) was obtained from the follow-up questionnaire in 2007. Log-binomial models were applied to calculate Risk Ratios with 95 percent Confidence Intervals (CI) comparing physically active and normal weight groups versus sedentary and overweight groups.

RESULTS

Compared to a sedentary leisure time, all measured levels of leisure time physical activity were associated with a greater chance of recovery from persistent back pain among women. The adjusted Risk Ratios was 1.46 (95% CI: 1.06, 2.01) for low leisure time physical activity, 1.51 (95% CI: 1.02, 2.23) for moderate leisure time physical activity, and 1.67 (95% CI: 1.08, 2.58) for high leisure time physical activity. There were no indications that leisure time physical activity influenced recovery among men, or that BMI was associated with recovery from persistent back pain either among men or among women.

CONCLUSIONS

Regular leisure time physical activity seems to improve recovery from persistent back pain among women.

The greatest risk for low-back pain among newly educated female health care workers; body weight or physical work load?

Background

Low back pain (LBP) represents a major socioeconomic burden for the Western societies. Both life-style and work-related factors may cause low back pain. Prospective cohort studies assessing risk factors among individuals without prior history of low back pain are lacking. This aim of this study was to determine risk factors for developing low back pain (LBP) among health care workers.

Methods

Prospective cohort study with 2,235 newly educated female health care workers without prior history of LBP. Risk factors and incidence of LBP were assessed at one and two years after graduation.

Results

Multinomial logistic regression analyses adjusted for age, smoking, and psychosocial factors showed that workers with high physical work load had higher risk for developing LBP than workers with low physical work load (OR 1.8; 95% CI 1.1–2.8). In contrast, workers with high BMI were not at a higher risk for developing LBP than workers with a normal BMI.

Conclusion

Preventive initiatives for LBP among health care workers ought to focus on reducing high physical work loads rather than lowering excessive body weight.

Risk factors of pregnancy-related lumbopelvic pain: a biopsychosocial approach

AIMS AND OBJECTIVES

To examine the associations between pain-related psychological and social factors and pregnancy-related lumbopelvic pain intensity and interference after controlling biological factors.

BACKGROUND

Pregnancy-related lumbopelvic pain is prevalent and has been shown to interfere with women's quality of life. Although pain is a multidimensional phenomenon known to be influenced by psychosocial factors, the majority of previous research on this pregnancy-related lumbopelvic pain has focused on biological factors.

DESIGN

Cross-sectional correlational research.

METHOD

A sample of 183 pregnant women with lumbopelvic pain was recruited from a medical center in northern Taiwan. Study participants provided demographic information and were administered the Brief Pain Inventory and a modified Catastrophising subscale of the Coping Strategies Questionnaire. Multiple regressions were used to examine the associations among the study variables.

RESULTS

Analyses indicated that lower education level was associated with higher pain intensity. Higher pain intensity during pregnancy and catastrophising cognitions were associated significantly with higher pain interference. Moreover, age moderated the strength of the association between pain intensity and pain interference. This association was stronger for older than for younger women.

CONCLUSIONS

This study identified the psychosocial factors associated with pregnancy-related lumbopelvic pain intensity (educational level) and interference (pain intensity and catastrophising) and also a variable (age) that moderated the association between pain intensity and pain interference. The findings support a biopsychosocial approach in understanding the experience and impact of pregnancy-related lumbopelvic pain.

RELEVANCE TO CLINICAL PRACTICE

Nurses should assess pregnant clients' age, educational level, pain intensity and pain catastrophising thoughts to help identify women who are more at risk for higher lumbopelvic pain intensity or interference. Women endorsing catastrophising cognitions should be referred to or provided with treatment to reduce the frequency of these cognitions that are known to have a negative impact on quality of life in other pain populations.

The effect of flooring on musculoskeletal symptoms in the lower extremities and low back among female nursing assistants

This study examines the effect of changing the floor from a 2-mm homogenous vinyl floor to a 4-mm heterogeneous vinyl floor (1.5-mm wear layer and 2.5-mm foam layer) on musculoskeletal symptoms in the lower extremities and low back among nursing assistants in a geriatric care centre. A pre-post design with a reference group consisting of nursing assistants from a similar geriatric care centre was used. Follow-up measurements were carried out 12 and 24 months after the intervention by means of questionnaires. At the 1-year follow-up, the pain intensity score in the feet of the intervention group had decreased compared with the baseline value and remained statistically significant at the 2-year follow-up. The decrease in pain intensity score of the feet in the intervention group was statistically significantly different from the reference group, both after 1 and 2 years.

PRACTITIONER SUMMARY

The results show the importance of flooring in the workplace with regard to reducing musculoskeletal symptoms. Appropriate flooring is especially important in the female-dominated health care sector, where workers must stand or walk for long periods.

Prevalence of musculoskeletal disorders among plastics industry workers

The prevalence of musculoskeletal disorders among workers in the plastics industry in Salvador, Bahia State, Brazil was estimated. Cases were defined by reported symptoms of pain in the previous 12 months, lasting more than a week or having monthly minimum frequency, which had given rise to restrictions at work or to seeking medical attention, or where respondents had a severity score greater than or equal to 3 (on a numerical scale of 0 to 5). A stratified proportional random sample of 577 workers was studied. The prevalence of musculoskeletal disorders, considering of all body segments, was 50.1%. The prevalence of musculoskeletal disorders was higher among women than among men at distal upper extremities (34.6% and 11.6% respectively) and also in the region of the neck, shoulder or upper part of the back (27.4% and 17.6% respectively). There was no difference between genders for the prevalence of lower back pain (21.2% and 21.4% respectively); 65% of cases in this region had reports of pain in the previous seven days. Due to the importance and prevalence of musculoskeletal disorders, it is necessary that their measurement in epidemiological studies be done properly.

Assessing agreement of self-reported and observed physical exposures of the upper extremity

Assessment of workplace physical exposures by self-reported questionnaires has logistical advantages in population studies, but is subject to exposure misclassification. This study measured agreement between eight self-reported and observer-rated physical exposures to the hands and wrists, and evaluated predictors of intermethod agreement. Workers (n = 341) from three occupational categories (clerical/technical, construction, and service) completed self-administered questionnaires and worksite assessments. Analyses compared self-reported and observed ratings using a weighted kappa coefficient. Personal and psychosocial factors, presence of upper extremity symptoms, andjob type were evaluated as predictors of agreement. Weighted kappa values were substantial for lifting (0.67) and holding vibrating tools (0.61), moderate for forceful grip (0.58), and fair to poor for all other exposures. Upper extremity symptoms did not predict greater disagreement between self-reported and observed exposures. Occupational category was the only significant predictor of inter-method agreement. Self-reported exposures may provide a useful estimate of some work exposures for population studies.

Studying the relationship between low back pain and working postures among those who stand and those who sit most of the working day

A relationship between low back pain (LBP) and prolonged standing or prolonged sitting at work has not been clearly shown, despite its biological plausibility. Because sitting and standing postures vary as to duration and freedom to alternate postures, and standing postures vary as to mobility, associations between specific working postures and LBP were explored using multiple logistic regression. Associations between work factors and self-reported LBP during the previous 12 months that interfered with usual activities were examined among 4493 standing workers and 3237 sitting workers interviewed in the 1998 Quebec Health and Social Survey; 24.5% reported significant LBP. Since the same conditions can correspond to different physiological demands for sitting compared with standing workers, analyses were performed separately for the two groups. Standing without freedom to sit was associated with LBP. Different occupational physical and psychosocial factors were associated with LBP in sitting compared with standing populations.

The predictive effect of fear-avoidance beliefs on low back pain among newly qualified health care workers with and without previous low back pain: a prospective cohort study

BACKGROUND

Health care workers have a high prevalence of low back pain (LBP). Although physical exposures in the working environment are linked to an increased risk of LBP, it has been suggested that individual coping strategies, for example fear-avoidance beliefs, could also be important in the development and maintenance of LBP. Accordingly, the main objective of this study was to examine (1) the association between physical work load and LBP, (2) the predictive effect of fear-avoidance beliefs on the development of LBP, and (3) the moderating effect of fear-avoidance beliefs on the association between physical work load and LBP among cases with and without previous LBP.

METHODS

A questionnaire survey among 5696 newly qualified health care workers who completed a baseline questionnaire shortly before completing their education and a follow-up questionnaire 12 months later. Participants were selected on the following criteria: (a) being female, (b) working in the health care sector (n = 2677). Multinomial logistic regression analysis was used to evaluate the effect of physical work load and fear-avoidance beliefs on the severity of LBP.

RESULTS

For those with previous LBP, physical work load has an importance, but not among those without previous LBP. In relation to fear-avoidance beliefs, there is a positive relation between it and LBP of than 30 days in both groups, i.e. those without and with previous LBP. No moderating effect of fear-avoidance beliefs on the association between physical work load and LBP was found among cases with and without LBP.

CONCLUSION

Both physical work load and fear-avoidance beliefs matters in those with previous LBP. Only fear-avoidance beliefs matters in those without previous LBP. The study did not find a moderating effect of fear-avoidance beliefs on the association between physical work load and LBP.

Validity of self-reported mechanical demands for occupational epidemiologic research of musculoskeletal disorders

OBJECTIVES

To describe the relation of the measured validity of self-reported mechanical demands (self-reports) with the quality of validity assessments and the variability of the assessed exposure in the study population.

METHODS

We searched for original articles, published between 1990 and 2008, reporting the validity of self-reports in three major databases: EBSCOhost, Web of Science and PubMed. Identified assessments were classified by methodological characteristics (eg, type of self-report and reference method) and exposure dimension was measured. We also classified assessments by the degree of comparability between the self-report and the employed reference method, and the variability of the assessed exposure in the study population. Finally, we examined the association of the published validity (r) with this degree of comparability, as well as with the variability of the exposure variable in the study population.

RESULTS

Of the 490 assessments identified, 75% used observation-based reference measures and 55% tested self-reports of posture duration and movement frequency. Frequently, validity studies did not report demographic information (eg, education, age, and gender distribution). Among assessments reporting correlations as measure of validity, studies with a better match between the self-report and the reference method, and studies conducted in more heterogeneous populations tended to report higher correlations [odds ratio (OR) 2.03, 95% confidence interval (95% CI) 0.89-4.65 and OR 1.60, 95% CI 0.96-2.61, respectively].

CONCLUSIONS

The reported data support the hypothesis that validity depends on study-specific factors often not examined. Experimentally manipulating the testing setting could lead to a better understanding of the capabilities and limitations of self-reported information.

Self-administered questionnaire and direct observation by checklist: comparing two methods for physical exposure surveillance in a highly repetitive tasks plant

BACKGROUND

We evaluated the agreement between a questionnaire and an observational checklist for exposure assessment in the setting of an upper-limb work-related musculoskeletal disorders (UWMSD) surveillance program in a population with a high level of physical exposures.

METHODS

A surveillance program was implemented in a large shoe factory. Physical exposures were assessed in 1996 by a self-administered questionnaire and by the direct observation of work tasks assessed using a checklist filled out by trained assessors. Items were summed into a "questionnaire" score and an "observational" score. These scores were compared by Pearson's correlation. The association between exposure assessment by each method and UWMSD incidence between 1996 and 1997, defined by a standardized examination, was also studied.

RESULTS

Correlation between the "questionnaire" score and the "observational" score was low among the 196 workers (77%) who received both evaluations (rho=0.06, p>0.05). Only exposure assessed by the questionnaire method was significantly associated with high incidence of UWMSD between 1996 and 1997, with good sensitivity (97%) and poor specificity (27%).

CONCLUSION

In this surveillance program, self-reported physical exposures assessed by questionnaire and by direct observation did not evaluate same dimensions of high physical exposures. In this sample, exposures assessed by questionnaire identified workers at high risk of incident UWMSD more precisely than exposures identified by direct observation.

Work-related musculoskeletal disorders in physical therapists: a prospective cohort study with 1-year follow-up

BACKGROUND

Work-related musculoskeletal disorders (WMSDs) have a significant impact on physical therapists, but few studies have addressed the issue. Research is needed to determine the scope of the problem and the effects of specific risk factors.

OBJECTIVES

The objectives of this study were: (1) to determine the 1-year incidence rate of WMSDs in physical therapists and (2) to determine the effects of specific risk factors.

DESIGN

This was a prospective cohort study with 1-year follow-up.

METHODS

Subjects were randomly selected American Physical Therapy Association members (N=882). Exposure assessment included demographic data, physical risk factors, job strain, and specific physical therapy tasks. The primary outcome was WMSDs, with a severity rating of at least 4/10 and present at least once a month or lasting longer than a week.

RESULTS

The response rate to the baseline questionnaire was 67%. Ninety-three percent of the subjects who responded to the baseline questionnaire responded to the follow-up questionnaire. The 1-year incidence rate of WMSDs was 20.7%. Factors that increased the risk for WMSDs included patient transfers, patient repositioning, bent or twisted postures, joint mobilization, soft tissue work, and job strain.

LIMITATIONS

The primary limitation of this study was the number of therapists who had a change in their job situation during the follow-up year.

CONCLUSIONS

Work-related musculoskeletal disorders are prevalent in physical therapists. Physical therapy exposures, patient handling, and manual therapy, in particular, increase the risk for WMSDs.

Comparison of two self-reported measures of physical work demands in hospital personnel: a cross-sectional study

Background

Low back pain (LBP) is a frequent health complaint among health care personnel. Several work tasks and working postures are associated with an increased risk of LBP. The aim of this study was to compare two self-reported measures of physical demands and their association with LBP (the daily number of patient handling tasks and Hollmann's physical load index).

Methods

A questionnaire was distributed to 535 hospital employees in a psychiatric and an orthopedic ward in a Danish hospital. Of these 411 (77%) filled in and returned the questionnaire. Only the 373 respondents who had non-missing values on both measures of physical demands were included in the analyses. The distribution of physical demands in different job groups and wards are presented, variance analysis models are employed, and logistic regression analysis is used to analyze the association between measures of physical demands and LBP.

Results

In combination, hospital ward and job category explained 56.6% and 23.3% of the variance in the self-reported physical demands measured as the daily number of patient handling tasks and as the score on the physical load index, respectively. When comparing the 6% with the highest exposure the prevalence odds ratio (POR) for LBP was 5.38 (95% CI 2.03–14.29) in the group performing more than 10 patient handling tasks per day and 2.29 (95% CI 0.93–5.66) in the group with the highest score on the physical load index.

Conclusion

In specialized hospital wards the daily number of patient handling tasks seems to be a more feasible measure of exposure when assessing the risk of LBP compared to more advanced measures of physical load on the lower lumbar spine.

Can individual health differences be explained by workplace characteristics?--A multilevel analysis

Research on work-related health has mainly focused on individual factors. The present study expands the focus by exploring the role of organizational characteristics of workplaces for different individual health outcomes. The aim of the study was to look at differences in relative effect of workplace variations on five health outcomes, and to explain those differences in health outcomes by organizational characteristics. The sample encompassed 90 workplaces in Sweden and about 4300 individuals employed within these workplaces. Measurement of the workplace characteristics was carried out independently of the measurement of the individual's working conditions and health. Organizational data were collected by interviews with local managers at participating workplaces, and individual data were obtained by means of a survey of the employees. The results showed that a significant proportion of the variance in sickness absence, work ability, general health, and musculoskeletal disorders was attributed to the workplace. Of eight tested organizational characteristics, customer adaptation, lean production, and performance control could explain some of this workplace variance. The results also showed that only one organizational effect remained significant when controlled for the individual confounder of age and gender. High customer adaptation is associated with higher sickness absence. This association is not mediated via differences in mental and physical job strain.

Selected questions on biomechanical exposures for surveillance of upper-limb work-related musculoskeletal disorders

OBJECTIVE

Questionnaires for assessment of biomechanical exposure are frequently used in surveillance programs, though few studies have evaluated which key questions are needed. We sought to reduce the number of variables on a surveillance questionnaire by identifying which variables best summarized biomechanical exposure in a survey of the French working population.

METHODS

We used data from 2002 to 2003 French experimental network of Upper-limb work-related musculoskeletal disorders (UWMSD), performed on 2,685 subjects in which 37 variables assessing biomechanical exposures were available (divided into four ordinal categories, according to the task frequency or duration). Principal Component Analysis (PCA) with orthogonal rotation was performed on these variables. Variables closely associated with factors issued from PCA were retained, except those highly correlated to another variable (rho > 0.70). In order to study the relevance of the final list of variables, correlations between a score based on retained variables (PCA score) and the exposure score suggested by the SALTSA group were calculated. The associations between the PCA score and the prevalence of UWMSD were also studied. In a final step, we added back to the list a few variables not retained by PCA, because of their established recognition as risk factors.

RESULTS

According to the results of the PCA, seven interpretable factors were identified: posture exposures, repetitiveness, handling of heavy loads, distal biomechanical exposures, computer use, forklift operator specific task, and recovery time. About 20 variables strongly correlated with the factors obtained from PCA were retained. The PCA score was strongly correlated both with the SALTSA score and with UWMSD prevalence (P < 0.0001). In the final step, six variables were reintegrated.

CONCLUSION

Twenty-six variables of 37 were efficiently selected according to their ability to summarize major biomechanical constraints in a working population, with an approach combining statistical analyses and existing knowledge.

The influence of work-related exposures on the prognosis of neck/shoulder pain

To determine associations between work-related exposures and the prognosis of self-reported neck/shoulder pain. This prospective cohort study was based on 803 working subjects who reported neck/shoulder pain at baseline. The proportion of subjects who 5-6 years later were symptom-free was calculated. Data concerning work-related biomechanical, psychosocial, and organizational exposures were collected at baseline. The Cox regression analyses were used to calculate the relative chances (RC) of being symptom-free at the end of the study for single exposures, and also for up to three simultaneous work-related exposures. Adjustments were made for sex and age. Only 36% of the subjects were symptom-free 5-6 years later. The relative chance for being symptom-free at the end of the study was 1.32 (95% CI = 0.99-1.74) for subjects who were exposed to sitting > or =75% of the working time and 1.53 (95% CI = 1.02-2.29) for subjects who were exposed to job strain, i.e., the combination of high demands and low decision latitude. The relative chance of being symptom-free at the end of the study was 0.61 (95% CI = 0.40-0.94) for subjects with at least two out of three simultaneous biomechanical exposures at work; manual handling, working with the hands above shoulder level, and working with vibrating tools. In a heterogeneous population with moderate nonspecific neck/shoulder pain, sedentary work enhanced the chance of being symptom-free 5-6 years later, whereas simultaneous exposures to at least two of manual handling, working with hands above shoulder level and working with vibrating tools were associated with a lower chance of being symptom-free at the end of the study. This could imply that subjects with neck/shoulder pain should avoid such simultaneous exposures.

Medium- and long-term reproducibility of self-reported exposure to physical ergonomics factors at work

INTRODUCTION

The literature is sparse on reproducibility of self-reported exposure to physical ergonomics risk factors for musculoskeletal disorders (MSDs). Aims of this study were to evaluate, in a cohort of workers interviewed up to three times: 1-year test-retest reliability; and 5- and 6-year recall of physical exposures. We also examined whether reproducibility was influenced by the presence of UE MSD or by technological changes introduced between the last two surveys.

METHODS

A cohort of automobile manufacturing employees was interviewed at baseline, one and six years later about work history, physical and psychosocial exposures at work, upper limb symptoms, injury and medical history, and demographics. Agreement between interviews was evaluated by intraclass correlation and Spearman coefficients. Differences in exposure between 1- and 6-year follow-up were analyzed by Wilcoxon matched-pairs signed-ranks test.

RESULTS

Large and significant decreases in work pace and physical effort were observed from baseline, although an upper extremity composite index was quite stable in the total population. One-year test-retest reliability was fair to good for the composite exposure index (ICC=0.58), whole-body vibration, handling parts, and tool use, but poor for the other variables considered. Long-term reproducibility, from baseline or 1-year follow-up to 6-year follow-up, was poor for the composite index and almost all single items. UE MSD case status influenced 1-year test-retest reliability, with subjects who changed case status from baseline displaying higher reliability, but not reproducibility of recalled exposures. A strong regression to the mean effect was observed on exposures reported at follow-up surveys.

CONCLUSIONS

Recalled ergonomics exposures could be employed in retrospective cohort studies as a somewhat reliable and unbiased estimate of the self-reported exposures that would have been obtained up to one year earlier, but not over a longer period (5-6 years). These longer-term results may have been limited by difficulty in matching jobs between interviews; also the regression to the mean effect likely contributed to reduce agreement. Changes in production technology and work organization produced a decrease in physical workload intensity and job pace, but did not have a substantial impact on an exposure index for the upper limb.

Prevalence and physical determinants of low back pain in a rural Chinese population

STUDY DESIGN

This was a community-based cross-sectional study that is part of an ongoing study of genetics and osteoporosis.

OBJECTIVES

To estimate the 1-year self-reported prevalence of low back pain (LBP); and to assess the association between physical exposures (occupation, physical stress, and vibration) and LBP in a rural Chinese population. This study also explored how these associations change when individuals with LBP report additional pains in other parts of the body.

SUMMARY OF BACKGROUND DATA

Little is known about the prevalence and determinants of LBP in rural developing populations, even though approximately half of the world's population, mostly from the developing world, is engaged in agriculture, a known strenuous activity.

METHODS

Families with at least three participating siblings residing in the surrounding rural region of Anqing city, Anhui Province, China, were invited to participate in the study through public announcements and direct invitations by village physicians. A questionnaire including demographics, physical exposures, and musculoskeletal pain was administered to 13,965 men and women (age, 25-64 years). Generalized estimating equations were used to estimate LBP prevalence and examine associations between LBP and physical exposures.

RESULTS

The 1-year prevalence of LBP was 64%. Twenty-five percent reported no pain at any body site. Women had higher prevalence of LBP than men across all age groups. Being a farmer, reporting moderate or heavy physical stress, and having had former or current exposures to vibration were positively associated with LBP (P < 0.05). Physical exposures were also associated with cases of LBP combined with other musculoskeletal pains, and generally, the more pains individuals reported, the more likely it was that they were farmers and were exposed to vibration.

CONCLUSION

A high prevalence of LBP and LBP with additional musculoskeletal pain existed in this rural Chinese sample. We found evidence of a link between physical exposures and LBP, and LBP with additional musculoskeletal pain. Further understanding of the characteristics and risk factors of LBP in rural developing areas is needed.

Measuring the physical demands of work in hospital settings: design and implementation of an ergonomics assessment

BACKGROUND

Assessing the physical demands of the heterogeneous jobs in hospitals requires appropriate and validated assessment methodologies.

METHODS

As part of an integrated assessment, we adapted Rapid Entire Body Assessment (REBA), using it in a work sampling mode facilitated by a hand-held personal digital assistant, expanding it with selected items from the UC Computer Use Checklist, and developed a scoring algorithm for ergonomics risk factors for the upper (UB) and lower body (LB).

RESULTS

The inter-rater reliability kappa was 0.54 for UB and 0.66 for LB. The scoring algorithm demonstrated significant variation (ANOVA p<0.05) by occupation in anticipated directions (administrators ranked lowest; support staff ranked highest on both scores). A supplemental self-assessment measure of spinal loading correlated with high strain LB scores (r=0.30; p<0.001).

CONCLUSION

We developed and validated a scoring algorithm incorporating a revised REBA schema adding computer use items, appropriate for ergonomics assessment across a range of hospital jobs.

Relationships between Work‐related Factors and Disorders in the Neck‐shoulder and Low‐back Region among Female and Male Ambulance Personnel

This cross-sectional study on a random sample of 1,500 ambulance personnel investigated the relationships between self-reported work-related physical and psychosocial factors, worry about work conditions, and musculoskeletal disorders among female and male ambulance personnel. Three different outcomes, complaints, activity limitation, and sick leave, for the neck-shoulder and low-back region, respectively, were chosen. Among the female personnel, physical demands was significantly associated with activity limitation in the neck-shoulder (OR 4.13) and low-back region (OR 2.17), and psychological demands with neck-shoulder (OR 2.37) and low-back (OR 2.28) complaints. Among the male personnel, physical demands was significantly associated with low-back complaints (OR 1.41) and activity limitation (OR 1.62). Psychological demands and lack of social support were significantly associated with neck-shoulder complaints (OR 1.86 and OR 1.58, respectively) and activity limitation (OR 3.46 and OR 1.71) as well as activity limitation due to low-back complaints (OR 2.22 and OR 1.63). Worry about work conditions was independently associated with activity limitation due to low-back complaints among the female (OR 5.28), and to both neck-shoulder and low-back complaints (OR 1.79 and OR 2.04, respectively) and activity limitation (OR 2.32 and OR 1.95) among the male personnel. In conclusion, the association patterns between physical and psychological demands and MSDs suggest opportunities for intervention.

Gender differences in self-reported physical and psychosocial exposures in jobs with both female and male workers

OBJECTIVE

The aim was to determine whether men and women with the same job are equally exposed to work-related physical and psychosocial risk factors for musculoskeletal complaints.

METHODS

Men (n = 491) and women (n = 342) in 8 jobs with both female and male workers completed a questionnaire on exposure to work-related risk factors. Gender, job title, and potential confounders were included in the final statistical models. Separate analyses were performed for desk workers and assembly workers.

RESULTS

For most risk factors gender differences in exposure were found. Among desk workers exposures were most often higher for women, which was the opposite for assembly workers.

CONCLUSIONS

Although exposure assessment relied on self-report, it seems unlikely that gender differences in reporting behavior completely explained gender differences in exposure. Thus, gender differences in exposure are present within the same job.

Awkward work postures: association with occupational gender segregation

BACKGROUND

Segregation of men and women into different jobs is often cited as one of the most plausible explanations for gender differences in exposure and musculoskeletal disorders.

METHODS

Direct measurements of sitting, arm, and trunk postures were taken with two different technical instruments on 156 subjects (78 matched pairs of one female and one male worker) over one full workday in diverse labor markets.

RESULTS

Exposure differences between workers were strongly associated with vertical occupational segregation (measured as level of status/authority). The results showed that this association was strongest for female-dominated jobs. Workers in female-dominated jobs with a low status/authority experienced longer duration in standing posture (P = 0.001), and higher frequency of arm elevation (P = 0.028 and 0.040 for the dominant and the non-dominant arm, respectively). They also had longer duration of work with bent trunk compared to corresponding workers with high status/authority (P = 0.035). The association was less pronounced for male-dominated jobs, and no such association was found for gender-integrated jobs.

CONCLUSION

The findings have implications for prevention as well as for future research.

Concordance between VDU-users' ratings of comfort and perceived exertion with experts' observations of workplace layout and working postures

The aim of the present study was to evaluate the concordance (agreement) between VDU-users' ratings of comfort and ergonomists' observations of workplace layout, and the concordance between VDU-users' ratings of perceived exertion and ergonomists' observations of working postures during VDU-work. The study population consisted of 853 symptom free subjects. Data on perceived comfort in different dimensions and data regarding perceived exertion in different body locations were collected by means of a questionnaire. Data concerning workplace layout and working postures were collected with an observation protocol, by an ergonomist. Concordance between ratings of comfort and observations of workplace layout was reasonably good for the chair and the keyboard (0.60, 0.58) and good regarding the screen and the input device (0.72, 0.61). Concordance between ratings of perceived exertion and observations of working postures indicated good agreement (0.63-0.77) for all measured body locations (neck, shoulder, wrist and trunk). In conclusion ratings of comfort and perceived exertion could be used as cost-efficient and user-friendly methods for practitioners to identify high exposure to poor workplace layout and poor working postures.

Standing, sitting and associated working conditions in the Quebec population in 1998

Working posture is an important determinant of musculoskeletal and vascular health. Knowledge of the context and type of postures is necessary in order to examine their associations with health-related outcomes. This study describes self-reported usual working postures in a population and their associations with other working conditions and demographic variables. The 1998 Quebec Health and Social Survey is a population-based survey of 11,986 private households in the province of Quebec. It contained a self-administered questionnaire, including an extensive occupational health section. The analyses in this study were limited to respondents with paid employment who had at least 6 months seniority in their current job, comprising 9,425 subjects. The overall prevalence of usual work in a standing posture is 58%; it is more common among men, workers under 25 years, those in the two lowest educational quintiles and those with incomes under 20,000 Canadian dollars. Only one person in six who works standing reports being able to sit at will. Women and men differ in the types of usual standing and sitting postures at work. Those who work standing and/or who work in more constrained postures are more likely to be exposed to other physical work demands, such as handling heavy loads, repetitive work, forceful exertion and low job decision latitude. The association between decision latitude and constrained postures is an important link between psychosocial and physical stressors in the workplace. In epidemiological studies, exposure covariation and interactions should be considered in the generation and interpretation of the associations between work postures and musculoskeletal disorders.

Internal consistency and validity of a new physical workload questionnaire

AIMS

To examine the dimensionality, internal consistency, and construct validity of a new physical workload questionnaire in employees with musculoskeletal complaints.

METHODS

Factor analysis was applied to the responses in three study populations with musculoskeletal disorders (n = 406, 300, and 557) on 26 items related to physical workload. The internal consistency of the resulting subscales was examined. It was hypothesised that physical workload would vary among different occupational groups. The occupations of all subjects were classified into four groups on the basis of expected workload (heavy physical load; long lasting postures and repetitive movements; both; no physical load). Construct validity of the subscales created was tested by comparing the subscale scores among these occupational groups.

RESULTS

The pattern of the factor loadings of items was almost identical for the three study populations. Two interpretable factors were found: items related to heavy physical workload loaded highly on the first factor, and items related to static postures or repetitive work loaded highly on the second factor. The first constructed subscale "heavy physical work" had a Cronbach's alpha of 0.92 to 0.93 and the second subscale "long lasting postures and repetitive movements", of 0.86 to 0.87. Six of eight hypotheses regarding the construct validity of the subscales were confirmed.

CONCLUSIONS

The results support the internal structure, internal consistency, and validity of the new physical workload questionnaire. Testing this questionnaire in non-symptomatic employees and comparing its performance with objective assessments of physical workload are important next steps in the validation process.