Work-related injury burden, workers' compensation claim filing, and barriers: Results from a statewide survey of janitors.

BACKGROUND: Janitors are a low-wage, ethnically and linguistically diverse, hard-to-reach population of workers with a high burden of occupational injury and illness. METHODS: Data from an extensive multimodal (mail, phone, web) survey of janitors in Washington State were analyzed to characterize their working conditions and occupational health experiences. The survey included questions on demographics, work organization and tasks, health and safety topics, and discrimination and harassment. The survey was administered in eight languages. RESULTS: There were 620 complete interviews. The majority completed the survey by mail (62.6%), and in English (85.8%). More than half of responding janitors were female (56.9%), and the mean age was 45 years. Twenty percent reported having a (health-care-provider diagnosed) work-related injury or illness (WRII) in the past twelve months. Women and janitors who were Latino had significantly higher relative risk of WRII. Increased risk was also associated with several work organization factors that may indicate poor working conditions, insufficient sleep, and possible depression. Half of injured janitors did not file workers' compensation (WC) claims. CONCLUSIONS: Janitors reported a high percentage of WRII, which exceeded previously published estimates from Washington State. Women and Latino janitors had significantly increased risk of WRII, and janitors' working conditions may influence the unequal distribution of risk. WRII surveillance via WC or medical care usage in janitors and other low-wage occupations may reflect substantial underreporting. Characterizing the nature of janitors' work experience can help identify avenues for prevention, intervention, and policy changes to protect the health and safety of janitors.

Improving Occupational Health Disparity Research: Testing a method to estimate race and ethnicity in a working population.

BACKGROUND: Race and ethnicity data are often absent from administrative and health insurance databases. Indirect estimation methods to assign probability scores for race and ethnicity to insurance records may help identify occupational health inequities. METHODS: We compared race and ethnicity estimates from the Bayesian Improved Surname Geocoding (BISG) formula to self-reported race and ethnicity from 1132 workers. RESULTS: The accuracy of the BISG using gender stratified regression models adjusted for worker age and industry were excellent for White and Latino males and Latino females, good for Black and Asian Pacific Islander males and White and Asian Pacific Islander females. American Indian/Alaskan Native and those who indicated they were "Other" or "More than one race" were poorly identified. CONCLUSION: The BISG estimation method was accurate for White, Black, Latino, and Asian Pacific Islanders in a sample of workers. Using the BISG in administrative datasets will expand research into occupational health disparities.

Work-related injury factors and safety climate perception in truck drivers.

INTRODUCTION: The trucking industry has a high burden of work-related injuries. This study examined factors, such as safety climate perceptions, that may impact injury risk. METHOD: A random sample of 9800 commercial driver's license holders (CDL) were sent surveys, only 4360 were eligible truck drivers. Descriptive statistics and logistic regression models were developed to describe the population and identify variables associated with work-related injury. RESULTS: 2189 drivers completed the pertinent interview questions. Driving less-than-truckload, daytime sleepiness, pressure to work faster, and having a poor composite score for safety perceptions were all associated with increased likelihood of work-related injury. Positive safety perception score was protective for odds of work-related injury, and increased claim filing when injured. CONCLUSIONS: Positive psychological safety climate is associated with decreased likelihood of work-related injury and increased likelihood that a driver injured on the job files a workers' compensation claim.

Predicting work-related incidence of lateral and medial epicondylitis using the strain index.

BACKGROUND: The Strain Index (SI) has been developed to evaluate the risk for developing a distal upper extremity disorder. The objective of this study is to determine if the SI predicts incidence cases of work-related lateral, medial, or any epicondylities (LEPI, MEPI, and EPI). METHODS: Six hundred seven workers were followed for up to 3.5 years, 70 developed EPI on the dominant side (44 LEPI, 13 MEPI, and 13 both). Survival analyses were conducted adjusting for demographic, psychosocial, and work organizational factors, with the SI as time-dependent variable. RESULTS: High exposure (SI > 5), older age, and self-perceived poor general health were associated with incidence of LEPI and EPI, but not MEPI. There was a significant relationship between higher scores of SI and LEPI, hazard ratio (HR) 2.00 (95% CI 1.04-3.87) for SI 5.1-12, HR 2.12 (95% CI 1.11-4.05) for SI > 12. CONCLUSIONS: The SI can effectively identify jobs with increased risk of developing incidence of LEPI.

Racial and ethnic disparities in workers' compensation claims rates.

BACKGROUND: Workers of color experience a disproportionate share of work-related injuries and illnesses (WRII), however, most workers' compensation systems do not collect race and ethnicity information, making it difficult to monitor trends over time, or to investigate specific policies and procedures that maintain or could eliminate the unequal burden of WRII for workers of color. The purpose of this study is to apply a Bayesian method to Washington workers' compensation claims data to identify racial and ethnic disparities of WRII by industry and occupation, improving upon existing surveillance limitations. Measuring differences in risk for WRII will better inform prevention efforts and target prevention to those at increased risk. METHODS: To estimate WRII by race/ethnicity, we applied the Bayesian Improved Surname Geocode (BISG) method to surname and residential address data among all Washington workers' compensation claims filed for injuries in 2013-2017. We then compare worker and injury characteristics by imputed race/ethnicity, and estimate rates of WRII by imputed race/ethnicity within industry and occupation. RESULTS: Black/African Americans had the highest rates of WRII claims across all industry and occupational sectors. Hispanic/Latino WRII claimants also had higher rates than Whites and Asian/Pacific Islanders in almost all industry and occupational sectors. For accepted claims with both medical and non-medical compensation, Bodily reaction/overexertion injuries accounted for almost half of the claims during this reporting period. DISCUSSION: The high rates of injury we report by racial/ethnic categories is a cause for major concern. Nearly all industry and occupation-specific rates of workers' compensation claims are higher for Black/African American and Hispanic/Latino workers compared to Whites. More work is needed to identify work-related, systemic, and individual characteristics.

Cleaning in the 21st Century: The musculoskeletal disorders associated with the centuries-old occupation - A literature review.

Workers performing cleaning duties experience higher injury rates, especially in the form of musculoskeletal disorders (MSDs), than other industries. It is essential to understand the inherent risks associated with the nature of this occupation. Based on the Balance Theory (Smith & Carayon-Sainfort, 1989), this review surveys the current literature, especially those published since the previous review paper (Kumar & Kumar, 2008), and identifies which elements contributing to MSD risks were examined: task, technology, organization, environment, individual, and their interactions. Thirty-nine research papers published between 2005 and 2021 are identified and summarized. Among these papers, task and individual elements received the most attention, at 42 and 34 occurrences, respectively. The interaction elements of technology-organization, technology-environment, and organization-environment received less than three mentions. The goal of this literature review is to update the knowledge base and identify current trends for the cleaning occupation. Possible interventions for risk reduction and future research directions are suggested.

Responsiveness of the QuickDASH and SF-12 in workers with neck or upper extremity musculoskeletal disorders: one-year follow-up.

INTRODUCTION Questionnaires that measure functional status such as the Disability of the Arm, Shoulder and Hand (QuickDASH) and the Medical Outcomes Study 12-item Short-Form Health Survey (SF-12) can quantify the impact of health on performance. Little is known about whether these questionnaires can be used as a tool for measuring disabilities among workers. We compare the responsiveness of these two functional status questionnaires to changes in clinical outcomes of neck or upper extremity musculoskeletal disorders (UEMSD) among active workers in a longitudinal study. METHODS We evaluated the effect size (ES) and standardized response means (SRM) of the QuickDASH and the SF-12 for 148 workers who were divided into four subgroups based on the diagnosis status change between baseline and 1-year visit. RESULTS The ES and SRM for QuickDASH scores were 0.6/0.6 for the 50 subjects who became incident symptomatic neck or UEMSD cases, 1.3/1.0 for the 18 subjects who became incident clinical cases of neck or UEMSD, -1.0/-1.1 for the 46 subjects who recovered from having neck or UEMSD symptoms, and -1.1/-1.1 for the 34 subjects who recovered from being neck or UEMSD clinical cases. The correspondent ES/SRM for the QuickDASH work module were 0.4/0.3, 0.7/0.5, -0.6/-0.4, and -1.0/-0.8, respectively. The correspondent ES/SRM for the physical component scores of SF-12 (PCS12) for the four subgroups were 0.2/0.2, -0.9/-0.6, 0.3/0.2, and 0.3/0.3, respectively. CONCLUSIONS The QuickDASH scores were responsive to changes among active workers who were neck or UEMSD symptomatic or clinical case. PCS12 scores were sufficient only for use in clinical case status change.

Temporary workers in Washington state.

BACKGROUND: Evidence regarding the unequal burden of occupational injuries between workers employed by temporary agencies and those in standard employment arrangements is unclear. Studies range from no significant differences in risk to substantial increased risk for temporary workers. The purpose of this study is to compare the workers' compensation experience of a large cohort of temporary agency employed workers with those in standard forms of employment. METHODS: Washington State Fund workers' compensation data were obtained for claims with injury dates from January 1, 2003 to June 30, 2006, resulting in 342,540 accepted claims. General descriptive statistics, injury rates (per 10,000 FTE), and rate ratios (temp agency/standard employer) were computed by injury type and industry. RESULTS: Temporary agency employed workers had higher rates of injury for all injury types, and higher median time loss (40 vs. 27 days) but lower time loss costs (median $1,224 vs. $1,914, P < 0.001) and lower medical costs ($3,026 vs. $4,087, P < 0.001) than standard arrangement workers. Temporary agency workers had substantially higher rates for "caught in" and "struck by" injuries in the construction (IRR 4.93; 95% CI 2.80-8.08) and manufacturing (IRR 4.05; 95% CI 3.25, 5.00) industry sectors. CONCLUSION: Temporary agency employed workers have higher claims incidence rates than those in standard employment arrangements. The rate ratios are twofold higher in the construction and manufacturing industry sectors. More research is needed to explore potential reasons for this disparity in occupational injuries. Industry or some measure of job exposure should be included when comparing injury rates in different types of employment in order to better identify areas for prevention.

Language preference and non-traumatic low back disorders in Washington State workers' compensation.

BACKGROUND: Workers in the United States with limited English proficiency likely perform more hazardous work, experience higher rates of work-related injury and illness, and have worse disability outcomes. METHODS: We conducted a descriptive study of employment characteristics, timeliness and utilization of workers' compensation (WC) insurance benefits, cost and occupational health outcomes for Washington State WC state fund, non-traumatic low back disorders (LBD) claimants by language preference. RESULTS: A greater proportion of Spanish language preferring (SLP) LBD claims filed were accepted and resulted in lost work time than English language preferring (ELP) LBD claims. There were significant differences in the demographic, employment, and occupational characteristics between the SLP and ELP compensable claimant populations. The SLP LBD compensable claimants had greater time loss duration, greater medical and total claim costs, more use of physical therapy and vocational services than the ELP LBD compensable claimants. With the exception of the timeliness for providing the first time loss payment, the time periods for provision of insurance benefits did not differ between the SLP and ELP populations. SLP compensable claimants received less back surgery and had comparable permanent partial disability payments to the ELP population. Employers were more likely to protest the acceptance of a SLP compensable than one in an ELP LBD compensable claim. CONCLUSION: For those injured workers accessing the Washington State WC system, we observed differences based on language preference for pre-injury, and workers compensation outcomes. Further research is needed to explain the observed differences.

Gender adjustment or stratification in discerning upper extremity musculoskeletal disorder risk?

OBJECTIVES: The aim was to explore whether "adjustment" for gender masks important exposure differences between men and women in a study of rotator cuff syndrome (RCS) and carpal tunnel syndrome (CTS) and work exposures. METHODS: This cross-sectional study of 733 subjects in 12 health care and manufacturing workplaces used detailed individual health and work exposure assessment methods. Multiple logistic regression analysis was used to compare gender stratified and adjusted models. RESULTS: Prevalence of RCS and CTS among women was 7.1% and 11.3% respectively, and among men 7.8% and 6.4%. In adjusted (gender, age, body mass index) multivariate analyses of RCS and CTS, gender was not statistically significantly different. For RCS, upper arm flexion >/=45 degrees and forceful pinch increased the odds in the gender-adjusted model (OR 2.66, 95% CI 1.26-5.59) but primarily among women in the stratified analysis (OR 6.68, 95% CI 1.81-24.66 versus OR 1.45, 95% CI 0.53-4.00). For CTS, wrist radial/ulnar deviation >/=4% time and lifting >/=4.5kg >3% time, the adjusted OR was higher for women (OR 4.85, 95% CI 2.12-11.11) and in the gender stratified analyses, the odds were increased for both genders (women OR 5.18, 95% CI 1.70-15.81 and men OR 3.63, 95% CI 1.08-12.18). CONCLUSIONS: Gender differences in response to physical work exposures may reflect gender segregation in work and potential differences in pinch and lifting capacity. Reduction in these exposures may reduce prevalence of upper extremity disorders for all workers.

Psychosocial factors and shoulder symptom development among workers.

BACKGROUND: Shoulder injuries are a common cause of pain and discomfort. Many work-related factors have been associated with the onset of shoulder symptoms. The psychosocial concepts in the demand-control model have been studied in association with musculoskeletal symptoms but with heterogeneous findings. The purpose of this study was to assess the relationship between the psychosocial concepts of the demand-control model and the incidence of shoulder symptoms in a working population. METHODS: After following 424 subjects for approximately 1 year, 85 incident cases were identified from self-reported data. Cox proportional hazards modeling was used to assess the associations between shoulder symptoms and demand-control model quadrants. RESULTS: Cases were more likely to be female and report other upper extremity symptoms at baseline (P < 0.05). From the hazard models, being in either a passive or high strain job quadrant was associated with the incidence of shoulder symptoms. Hazard ratios were 2.17, 95% CI 1.02-4.66 and 2.19, 95% CI 1.08-4.42, respectively. CONCLUSIONS: Using self-reporting to determine demand-control quadrants was successful in identifying subjects at risk of developing work-related shoulder symptoms. Research is needed to determine if this relationship holds with clinically diagnosed shoulder and other upper extremity musculoskeletal disorders. This may be part of a simple tool for assessing risk of developing these UEMSDs.

Quantitative exposure-response relations between physical workload and prevalence of lateral epicondylitis in a working population.

BACKGROUND: Lateral epicondylitis is a common work-related musculoskeletal disorder. The objective of this study was to identify risk factors associated with lateral epicondylitis among active workers. METHODS: Seven-hundred thirty-three workers in 12 Washington worksites participated in structured interviews, physical examinations, and individual exposure assessments of biomechanical and psychosocial factors. Multivariable logistic modeling was used. RESULTS: Thirty-eight subjects (5.2%) had lateral epicondylitis. Age (36-50 years-old), being female, and low social support at work were significant risk factors. Frequency of forceful exertion (> or =5 vs. < 1 times/min (OR 5.17, 95%CI 1.78-15.02), and > or =1 to <5 vs. <1 (OR 4.47, 95%CI 1.57-13.71)) and forearm supination at > or =45 degrees for > or =5% of the time with high lifting force (OR = 2.98, 95% CI 1.18-7.55) were significant physical load factors. CONCLUSIONS: Frequency of forceful exertion or a combination of forearm supination and forceful lifting were significant physical factors and should be considered for prevention strategies.

Evaluation of a symptom diagram for identifying carpal tunnel syndrome.

BACKGROUND: Hand symptom diagrams (HSDs) for rating the distribution of paraesthesias are proposed for use in epidemiological studies of carpal tunnel syndrome (CTS). AIM: To assess the validity of HSDs in a working population of manufacturing and service workers participating in a prospective study of musculoskeletal disorders. METHODS: Assessment of each subject involved completing a HSD, a heath assessment and electrodiagnostic studies (EDSs). HSDs were rated for CTS blinded to the health assessment and EDS results. The validity assessments of HSD used EDS as the sole confirmatory standard for CTS. RESULTS: A total of 733 subjects (65% of those eligible) participated in the study and 720 underwent EDSs. Dominant hand prevalence of a positive HSD and delayed nerve conduction studies in this working population was 9.2 per 100 workers. The sensitivity of a positive HSD for all workers was 0.28. By restricting the population to those workers with any current hand symptoms or to any worker with neuropathic hand symptoms, the sensitivities of HSD improved to 0.61 and 0.79, respectively. The positive predictive value of a HSD, with our study prevalence, was 0.48. CONCLUSIONS: The HSD classification schema has poor validity when applied to a general working population but improves when applied to workers with current neuropathic symptoms. The high number of false-negative HSDs in the general study population is most likely to be due to the inadequacies of using EDS as the confirmatory test. With a low prevalence of CTS, the positive predictive value for HSDs is poor.

Work-related injuries among commercial janitors in Washington State, comparisons by gender.

INTRODUCTION: We analyzed workers' compensation (WC) data to identify characteristics related to workers' compensation claim outcomes among janitorial service workers in Washington State. METHOD: We analyzed WC data from the Washington State Department of Labor & Industries (L&I) State Fund (SF) from January 1, 2003 through December 31, 2013, for janitorial service workers employed in the National Occupational Research Agenda (NORA) Services Sector. We constructed multivariable models to identify factors associated with higher medical costs and increased time lost from work. RESULTS: There were 2,390 janitorial service compensable claims available for analysis. There were significant differences in injury type and other factors by gender, age, and language preference. Linguistic minority status was associated with longer time loss and higher median medical costs. Women were estimated to account for 35% of janitorial service workers but made up 55% of the compensable claims in this study. CONCLUSIONS: Janitorial service workers comprise a large vulnerable occupational group in the U.S. workforce. Identifying differences by injury type and potential inequitable outcomes by gender and language is important to ensuring equal treatment in the workers' compensation process. PRACTICAL APPLICATIONS: There were significant differences in injury and individual characteristics between men and women in this study. Women had twice the estimated rate of injury to men, and were more likely to require Spanish language materials. Improving communication for training and knowledge about the workers' compensation system appear to be high priorities in this population of injured janitorial service workers.

Work related injuries in Washington State's Trucking Industry, by industry sector and occupation.

BACKGROUND: The trucking industry continues to have some of the highest work-related injury and illness rates and costs of any industry in the United States. Until recently, little focus has been placed on addressing non-motor vehicle collision related injuries within the trucking industry. Drivers are exposed to multiple physical risk factors that contribute to occupational injuries in order to complete their job duties, such as loading/unloading freight, decoupling trailers, strapping down loads and ingress and egress from the cab and trailer. About one-fourth of all truck driver injuries in the United States are related to slips, trips, and falls near the truck. PURPOSE: The purpose of this descriptive study is to report on recent injuries in the trucking industry in Washington State. Data are presented by occupation and industry sector, in order to better understand the magnitude of specific injuries in terms of time-loss days and workers' compensation costs. METHODS: All accepted, compensable (time-loss) claims from 2005 to 2010 within the trucking industry in Washington State were reviewed. Counts, rates, median and quartile data are presented. Logistic regression models are presented to identify factors associated with more severe claims. RESULTS: Non-traumatic musculoskeletal disorders of the neck, back and upper extremities are the most frequent injuries across all industry sectors and occupations in the trucking industry. Vehicle related claims had the highest median costs and time loss days and Courier and Messenger claims had the highest risk for higher time loss claims. Injuries varied substantially by sector and within sectors by occupation. CONCLUSION: It is important to review work-related injuries within the trucking industry by sector and occupation in order to maximize limited resources for injury prevention within this important sector.

The association between combination of hand force and forearm posture and incidence of lateral epicondylitis in a working population.

OBJECTIVE: The objective of this prospective study is to investigate the exposure-response relationships between various workplace physical exposures of force, repetition, and their combination assessed at an individual level with lateral epicondylitis (LE). BACKGROUND: Workplace upper extremity musculoskeletal disorders (UEMSDs) are prevalent, disabling, and expensive. LE is one of the major UEMSDs in active workers. METHOD: We used detailed health history, symptoms, and physical examination for identifying incidence and detailed exposure assessment to capture work tasks of each worker and to measure quantitative mechanical workload. We used counting process style input of proportional hazards regression for modeling cumulative incidence that accounts for changed exposure estimates during the follow-up period when respondents change jobs. RESULTS: The incidence rate of LE on the dominant side was 4.91 per 100 person-years. Adjusted for age and gender, the combined effect of forearm pronation > or = 45 degrees for > or = 40% of time and time spent with forceful exertion, including any power grip (hazard ratio [HR] = 2.8, 95% confidence interval [CI] = [1.35-5.77]), lifting for > or = 3% of time (HR = 2.50, 95% CI = [1.19-5.24]), and duty cycle for forceful exertion for > or = 10% (HR = 2.25, 95% CI = [1.09-4.66]), were significant predictors of dominant side LE, whereas neither the awkward posture nor the forceful exertion alone was significant. Older workers with jobs requiring a high percentage of time working with force in combination with awkward postures of forearm were more likely to predict LE. CONCLUSION: This study shows the evidence of the etiologic role of strenuous manual tasks in the occurrence of LE.

Inter-rater reliability of physical examinations in a prospective study of upper extremity musculoskeletal disorders.

OBJECTIVE: To test the inter-rater reliability of physical examinations for upper extremity musculoskeletal disorders. METHODS: A total of 111 subjects were examined by both an occupational medicine physician and a physical therapist, who were blinded to each others' tests results and subjects' current symptoms and health histories. RESULTS: Inter-rater reliability was moderate to excellent (0.52 to 0.88) for shoulder tests but required the inclusion of symptoms for increased inter-rater reliability of fair to excellent (0.27 to 0.57) for the elbow and hand/wrist tests. CONCLUSIONS: With the lack of "gold standard" tests, it is important that epidemiologic field studies conduct and report inter-rater reliability testing results between study examiners. It is important for researchers to report the results of inter-rater reliability, so that practitioners can weigh the results of study findings to improve both their diagnosis and treatment of these costly injuries.

The natural course of carpal tunnel syndrome in a working population.

OBJECTIVE: The aim of this study was to assess prevalence, incidence, and persistence of carpal tunnel syndrome (CTS) and associated symptoms over a one-year period in a working population. METHODS: We conducted a one-year prospective study of 418 active workers in 12 worksites. Detailed health interviews, psychosocial questionnaires, and electrophysiological studies [ie, nerve conduction velocity (NCV) tests] were conducted at baseline and one-year follow-up. Individual-observed exposure assessments of wrist posture, hand activity, and hand forces were conducted. RESULTS: Prevalence of CTS cases at baseline was 10.8% [95% confidence interval (95% CI) 7.8-13.7%] on the dominant side and 6.0% (95% CI 3.7-87.3%) on the non-dominant side; CTS symptoms were 14.1% (95% CI 10.8-17.5%) and 11.0% (95% CI 8.0-14.0%), respectively. Incidence of CTS cases were 7.5% (95% CI 4.8-10.2%) and 5.6% (95% CI 3.3-7.9%), respectively. Higher proportions of subjects with current symptoms or positive electrophysiological test findings at baseline became CTS cases at one year compared to those with neither (28.6% and 13.9%, respectively, versus 0.5%). One-year persistence of CTS case status was 44.4% (95% CI 29.9-59.0%) for the dominant hand and 52.0% (95% CI 32.4-71.6) for non-dominant hand. There were significant differences at baseline between asymptomatic subjects and CTS cases with respect to higher job demands (P=0.027), lower job satisfaction (P=0.036), lower general health (P=0.0009), higher exposure to vibrating hand tool use (P=0.039), and greater time using a forceful power grip (P=0.035) among cases. CONCLUSIONS: CTS symptoms more than positive NCV test results alone appear to predict CTS at one year. Persistence of CTS at one year is high.

Assessing validity of the QuickDASH and SF-12 as surveillance tools among workers with neck or upper extremity musculoskeletal disorders.

The purpose of this article was to assess validity of the regional Disabilities of Arm, Shoulder, and Hand (QuickDASH) and Short-Form 12 (SF-12) for surveillance purpose. We compared the predictive, discriminate, and concurrent validity of the QuickDASH and SF-12 among 231 workers with specific clinical diagnoses of neck or upper extremity musculoskeletal disorders (UEMSDs) and 175 workers with symptoms only. Compared to those with symptoms only, the odds of being any neck or UEMSD case were 1.45 (95% confidence interval [95% CI]: 1.24-1.70) and 0.66 (95% CI: 0.48-0.91) with every 10-point increase in QuickDASH disability and physical component scale (PCS-12) scores, respectively. The clinical cases had significantly higher QuickDASH disability (23.0 vs. 14.3, p<0.0001) and lower PCS-12 scores (44.8 vs. 47.3, p=0.0133) than those with symptom only. The QuickDASH disability scores were moderately correlated with the PCS-12 scores (rho=-0.40) among the clinical cases. Either QuickDASH or PCS-12 can be used as a simple surveillance tool in an active working population.