Validity and responsiveness of the work functioning impairment scale (WFun) in workers with pain due to musculoskeletal disorders

Prevalence and associated factors of work impairment among geriatricians during the COVID-19 pandemic in Japan

AIM

This study investigated work impairment and its associated factors among geriatricians during the coronavirus disease 2019 (COVID-19) pandemic.

METHODS

This cross-sectional study was carried out using an anonymous online survey questionnaire administered to members of the Japanese Geriatric Society between October and December 2022. The questionnaire included questions regarding psychological distress (Kessler Psychological Distress Scale), fear of COVID-19 (Fear of COVID-19 Scale) and work impairment (Work Functioning Impairment Scale). Multivariate logistic regression analyses were carried out to determine the factors associated with work impairment. Causal mediation analyses were performed to delineate the relationship between work impairment, psychological distress and fear of COVID-19.

RESULTS

The analytic sample included 386 geriatricians, and work impairment was observed in 24.8% of them. Work impairment was associated with age, prefecture where the institution was located and fear of COVID-19. Mediation analysis showed that the effect of fear of COVID-19 on work impairment was almost completely mediated by psychological distress.

CONCLUSION

During the COVID-19 pandemic, work impairment was commonly observed among geriatricians. We found that fear of COVID-19 might cause work impairment; however, this effect was exerted entirely through psychological distress. This implies that interventions to prevent or reduce work impairment among doctors should mainly target psychological distress; however, the fear of COVID-19, if it causes psychological distress, should also be addressed. Managers of hospitals and long-term care facilities must take steps to protect healthcare workers' mental well-being and maintain work productivity. Therefore, understanding the factors related to work impairment might help them devise effective measures. Geriatr Gerontol Int 2024; 24: 215-220.

Impact of COVID-19 Infection on Work Functioning in Japanese Workers: A Prospective Cohort Study

Background

The impact of COVID-19 infection on workers' work function persists even after the acute phase of the infection. We studied this phenomenon in Japanese workers.

Methods

We conducted a one-year prospective cohort study online, starting with a baseline survey in December 2020. We tracked workers without baseline work functioning impairment and incorporated data from 14,421 eligible individuals into the analysis. We estimated the incidence rate ratio for new onset of work functioning impairment due to COVID-19 infection during follow-up, using mixed-effects Poisson regression analysis with robust variance.

Results

Participants reporting infection between January and December 2021 showed a significantly higher incidence of new work functioning impairment (adjusted incidence rate ratio: 2.18, 95% confidence interval: 1.75-2.71, p < 0.001). The formality of the recuperation environment correlated with a higher risk of work functioning deterioration in infected individuals (p for trend <0.001).

Conclusion

COVID-19-infected workers may continue to experience work difficulties due to persistent, post-acute infection symptoms. Companies and society must urgently provide rehabilitation and social support for people with persistent symptoms, recognizing that COVID-19 is not just a transient acute infection.

The role of discrimination in the relation between COVID-19 sequelae, psychological distress, and work impairment in COVID-19 survivors

Perceived discrimination and work impairment are commonly observed in COVID-19 survivors, but their relationship has not been well understood. We aimed to evaluate the role of discrimination in the development of psychological distress and work impairment in COVID-19 survivors. From April 2020 to November 2021, 309 patients were recruited at two designated COVID-19 hospitals in Japan. Participants completed a standardized questionnaire including COVID-19 sequelae, psychological distress, impairments in work performance and perceived discrimination. The majority of participants (62.5%) experienced one or more COVID-19 sequelae. Psychological distress was observed in 36.9% and work impairment in 37.9%. In multivariate logistic regression analyses, COVID-19 sequelae and discrimination were associated with both psychological distress and work impairment. Mediation analysis demonstrated that the direct effect of sequelae on work impairment was non-significant after accounting for psychological distress, suggesting that the effect of sequelae on work impairment was mainly mediated through psychological distress. These findings were replicated in a subgroup analysis limited to patients with mild COVID-19. We conclude that discrimination plays an important role in the development of psychological distress and work impairment, and that both discrimination and psychological distress should be targets of intervention in COVID-19 survivors.

Disrupted care during the COVID-19 state of emergency and productivity loss attributed to presenteeism in workers: a nationwide cross-sectional study

OBJECTIVES

The COVID-19 pandemic has caused medical care delays and avoidance around the globe. However, little is known about the relationship between disrupted care and productivity loss attributed to presenteeism during the COVID-19 pandemic. We aimed to investigate whether disrupted care during the COVID-19 state of emergency was associated with health status and productivity loss.

METHODS

We used data from a nationwide, cross-sectional, Internet-based, self-administered survey. We performed multiple logistic regression analysis on data from 14 545 participants to investigate the associations among variables related to disrupted care, health status and the Work Functioning Impairment Scale, with a cut-off of 21 points.

RESULTS

Participants who experienced exacerbation of underlying disease (adjusted OR (aOR) 2.84; 95% CI 2.28 to 3.53) or any type of disrupted care were more likely to show low productivity at work. Experiencing disruptions in routine and non-routine clinical settings (aOR 4.64; 95% CI 3.64 to 5.92 and aOR 6.29; 95% CI 4.74 to 8.34, respectively), and running out of drugs (aOR 6.13; 95% CI 4.60 to 8.18) were strongly associated with exacerbation of underlying disease.

CONCLUSIONS

Workers who experienced disrupted care were much more likely to show productivity loss. Exacerbation of underlying disease is one possible pathway through which disrupted care could affect productivity loss attributed to presenteeism. Our study provides evidence of the importance of early diagnosis and continuous treatment of non-COVID-19 patients to enable them to remain healthy and continue to work during the pandemic.

Effect of Psychological Distress on the Association of Workplace Social Capital with Presenteeism and Sickness Absence

Greater workplace social capital (WSC) can be related to workers' health and productivity. We sought to clarify the association between horizontal WSC and presenteeism and sickness absence (SA) and to examine the effects of psychological distress on these associations among Japanese workers. A cross-sectional study was conducted in 2017 at seven large Japanese companies. Logistic regression analysis was performed with presenteeism and SA as the dependent variables, horizontal WSC as an independent variable, and sociodemographic characteristics and psychological distress as covariates. After adjustment for sociodemographic characteristics, the results showed that greater horizontal WSC was associated with lower presenteeism and SA. The odds ratios for the relationship between horizontal WSC and presenteeism and that between horizontal WSC and SA dropped moderately after adjustment for psychological distress but remained significant. Further exploration of the factors underlying the relationship between WSC and productivity is needed to confirm if WSC enhances workers' health and productivity and to inform the development of effective occupational health initiatives.

Relationship between impaired work function and coping behaviors in workers with low back pain

OBJECTIVES

The aim of the present study was to clarify the relationship between work functional impairment levels and three coping behaviors of workers with low back pain, which were about seeking medical attention, taking over-the-counter drugs, and taking self-care.

METHODS

We conducted a cross-sectional study on 14 Japanese companies in 2016. Work function impairment was measured using the Work Functioning Impairment Scale. Logistic regression analyses were conducted for the three coping behaviors and odds ratios (ORs) calculated for work functional impairment levels.

RESULTS

We analyzed 2232 subjects; 226 were women and 790 worked on production lines. 688 workers had sought medical attention, 436 had taken over-the-counter medication, and 1225 had engaged in self-care. Those seeking medical attention were associated with severe work function impairment compared with no work function impairment (adjusted OR = 2.84, 95% confidence interval: 1.82-4.45, p < .001). We observed a trend for the association between over-the-counter drug use with high levels of work function impairment (adjusted OR: 1.19 for low, 1.35 for moderate, 1.65 for severe). There was no apparent relationship between self-care and the degree of work functional impairment.

CONCLUSION

In workers with low back pain, severe work functional impairment may promote medical attention and over-the-counter medication use, but it would not encourage self-care, such as stretching or exercise. Therefore, workplaces need to provide special support to help them take care of themselves. Therefore, it is desirable to provide good support for self-care in the workplace.

Presenteeism among workers: health-related factors, work-related factors and health literacy

BACKGROUND

Presenteeism is an important factor in workers' health. However, few studies have examined how variables such as socio-economic status, health status, workplace status and health literacy correlate with and affect presenteeism.

AIMS

To assess the correlates of presenteeism with a focus on health-related factors, work-related factors and health literacy.

METHODS

We conducted a cross-sectional study of 2914 Japanese workers from one company. We used a self-administered questionnaire to assess socio-demographic characteristics, health status, work environment, presenteeism and health literacy.

RESULTS

Forty-one per cent of participants were under 40 years of age and 70% were male. We found that 59% of the participants were at high risk of presenteeism. Presenteeism was associated with sex, age, household income, marital status, health-related factors (i.e. self-rated health status, dietary choices, exercise habits), work-related factors (i.e. workplace support, job demands, job control) and health literacy. Logistic regression analyses indicated that presenteeism was associated with self-rated health status, overtime hours, workplace support, job demands, job control and health literacy after adjusting for sex, age and income.

CONCLUSIONS

Health-related factors, work-related factors and health literacy are all associated with presenteeism. Improving the workplace environment, especially factors such as overtime working hours, workplace support, job demands and job control, and increasing health literacy may reduce presenteeism among general office workers.

Construct validity and test-retest reliability of the World Mental Health Japan version of the World Health Organization Health and Work Performance Questionnaire Short Version: a preliminary study

The aim of the study was to investigate test-retest reliability and construct validity of the World Mental Health Japan (WMHJ) version of World Health Organization Health and Performance Questionnaire (WHO-HPQ) short version according the COSMIN standard. We conducted two consecutive surveys of 102 full-time employees recruited through an Internet survey company in Japan, with a two-week interval in 2018. We calculated Pearson's correlation (r) of measures of the WHO-HPQ with other presenteeism scales (Stanford Presenteeism Scale, Work Functioning Impairment Scale, and perceived relative presenteeism), health and psychosocial job conditions. We tested the test-retest reliability (intraclass correlation, ICC) among those who reported no change of job performance during the follow-up. Among 92 (90%) respondents, the absolute presenteeism significantly correlated with WFun and perceived relative presenteeism (r=-0.341 and -0.343, respectively, p=0.001) and psychological distress (r=-0.247, p=0.018). The absolute/relative absenteeism did not significantly correlate with the other covariates. The test-retest reliability over a two-week period was high for the WHO-HPQ absolute presenteeism (ICC, 0.73), while those for absolute/relative absenteeism measures were moderate. The study found an adequate level of test-retest reliability, but limited support for the construct validity of the absolute presenteeism measure of the WMHJ version of the WHO-HPQ. Further research is needed to investigate the construct validity of the WHO-HPQ measures in a larger sample.

The Relationship Between Fear-avoidance Beliefs in Employees with Chronic Musculoskeletal Pain and Work Productivity: A Longitudinal Study

This study aimed to identify risk factors for chronic musculoskeletal pain (CMSP) and sought to examine the effect of fear-avoidance beliefs (FABs) on work productivity in workers with CMSP. We performed a longitudinal study using self-administered questionnaires given to employees in three different industries between April 2016 and March 2017. The questionnaire concerned background characteristics, work-related factors and musculoskeletal pain, the Work Functioning Impairment Scale (WFun), and the Japanese version of the Tampa Scale for Kinesiophobia (TSK-J). We performed logistic regression analysis to evaluate factors affecting CMSP and a multi-way analysis of variance to analyze the relationship between FABs and CMSP and the effect of FABs on the ability to function at work. Age (odds ratio [OR] = 1.02, 95% confidence interval [CI]: 1.00-1.03), mean working hours (OR = 1.18, 95% CI: 1.04-1.33), and changes in working hours (OR = 1.18, 95% CI: 1.02-1.37) were significantly associated with CMSP. Regarding FABs, we found that the stronger the FAB, the greater the WFun score, and that an increase in FABs resulted in a significant increase in WFun scores. This study demonstrated that long or increased working hours may be risk factors for CMSP, and that stronger FABs in those with CMSP are associated with decreased ability to function at work. In addition, measures to reduce FABs in workers with CMSP may be effective.

The Interaction Between Pain Intensity and Pain Self-Efficacy in Work Functioning Impairment: A Cross-Sectional Study in Japanese Construction Workers

OBJECTIVE

To examine the pain intensity and pain self-efficacy interaction in workers' work functioning impairment.

METHODS

A cross-sectional study using a self-reporting survey. Of 6657 Japanese construction company employees, 5129 (77.0%) valid responses were analyzed for work functioning impairment. Further analysis using current pain intensity and pain self-efficacy was performed on 1622 employees who experienced physical pain in the past 12 months.

RESULTS

Pain intensity showed a dose-response relationship with work functioning impairment. Further analysis showed an interaction between pain intensity and pain self-efficacy for work functioning impairment. Stratification by pain self-efficacy showed that high pain self-efficacy was not associated with an increase in work functioning impairment, even in those with severe pain (odds ratio = 1.79; 95% confidence interval = 0.69 to 4.68).

CONCLUSIONS

Pain self-efficacy may be a key determinant for work functioning impairment in workers with pain.

Near misses and presenteeism among paramedics

BACKGROUND

Paramedics need to be in good physical health to be able to respond to emergencies. We hypothesized that near misses by paramedics and unanticipated incidents that cause no harm may be associated with presenteeism during emergency rescues.

AIMS

To examine the association between presenteeism and near misses among paramedics.

METHODS

A cross-sectional study was conducted among 254 paramedics using a self-administered questionnaire. Presenteeism was measured using the work functioning impairment scale (WFun).

RESULTS

Twelve per cent of respondents experienced high work function impairment indicating presenteeism. The rate of near-miss experiences steadily increased with increasing work function impairment among paramedics (WFun score category: middle, odds ratio (OR) 3.62, 95% confidence interval (CI) 1.62-8.11; high, OR 4.36, 95% CI 1.37-13.84; very high, OR 8.62, 95% CI 2.09-35.48).

CONCLUSIONS

This study demonstrated a positive relationship between impaired work function indicating presenteeism and near misses among paramedics. This suggests that presenteeism may be associated with errors that have the potential to cause serious accidents. Improved access to treatment for frequent health problems may reduce the number of incidents among paramedics.

Validity and Responsiveness of the Work Functioning Impairment Scale in Workers With Depression

OBJECTIVE

We aimed to evaluate the convergent validity and responsiveness of the work functioning impairment scale (WFun) in patients with depression, a major disease causing presenteeism.

METHODS

Baseline testing was performed using WFun, the Quick Inventory of Depressive Symptomatology (QIDS), 17-item Hamilton Depression Rating Scale (HAM-D), and Montgomery-Asberg Depression Rating Scale (MADRS) in 37 outpatients with major depression or bipolar disorder who were working. The QIDS and WFun scores were measured several times for responsiveness evaluation.

RESULTS

Regression analyses showed significant positive correlations between baseline WFun and HAM-D and MADRS scores. Changes in WFun and QIDS scores were positively correlated for QIDS scores.

CONCLUSIONS

Our results suggest that WFun is convergently valid and responsive for determining the clinical severity of depression in workers treated as psychiatric outpatients.

Validity and responsiveness of the Work Functioning Impairment Scale (WFun) in rheumatoid arthritis patients: A multicenter prospective study

Objective: Previous studies have not fully evaluated the measurement properties of the Work Functioning Impairment Scale (WFun) in clinical situations and there are no data from patients with rheumatoid arthritis (RA). This study aimed to investigate the convergent validity and responsiveness of the WFun in patients with RA.Methods: This substudy was a part of the multicenter, observational, prospective FIRST ACT-SC study. In total, 322 paid workers with RA received anti-rheumatic drugs at baseline. The WFun, Disease Activity Score based on 28 joints and erythrocyte sedimentation rate (DAS28-ESR), Clinical Disease Activity Index (CDAI), Simplified Disease Activity Index (SDAI), Work Productivity and Activity Impairment Questionnaire (WPAI), and Japanese Health Assessment Questionnaire Disability Index (HAQ-DI) were administrated at baseline and weeks 12, 24, and 52. Multilevel regression analyses were performed.Results: High average WFun scores were associated with higher score categories of the DAS28-ESR, CDAI, SDAI, WPAI and HAQ-DI. Average WFun change scores linearly decreased with decreases on each instruments.Conclusion: The findings indicate that the WFun has reasonable measurement properties: the scale demonstrated validity and responsiveness with RA patients. The WFun could be useful in assessing presenteeism in patients with RA.

Cross-cultural validation of the work functioning impairment scale (WFun) among Japanese, English, and Chinese versions using Rasch analysis

Objectives

The work functioning impairment scale (WFun) was developed to measure the degree of work functioning impairment in Japanese workers based on the Rasch model. Given that the number of foreign workers employed in Japan and abroad has increased in recent years, a multilingual questionnaire is becoming increasingly necessary to investigate work functioning impairment in these workers. The purpose of this study was to verify the cross‐cultural validity of WFun between Japanese, Chinese, and English versions.

Methods

A cross‐sectional study was conducted in two stages. First, the Chinese and English versions of WFun were created. Second, an internet survey was conducted among 1000 Japanese, 400 Chinese, and 300 Americans. Estimates and standard errors of an individual's ability and item difficulty were calculated using the Rasch model. Differential item functioning (DIF) and differential test functioning (DTF) were also examined using Rasch model analyses.

Results

The effect size of DIF for one item in the English version exceeded 0.5 logit, indicating the presence of some DIF. In contrast, the effect sizes of DIF for all other items were below 0.5 logit, indicating that the influence of DIF was negligible. Furthermore, Rasch measurements according to the raw score for each version of WFun showed strong agreement among the three versions, with an intraclass correlation of 0.98 (95% confidence interval: 0.97‐0.99), indicating the absence of DTF.

Conclusions

Our findings indicate that the English, Chinese, and Japanese versions of WFun have good comparability.