Sustained employability of workers in a production environment: design of a stepped wedge trial to evaluate effectiveness and cost-benefit of the POSE program

A Bayesian adaptive design approach for stepped-wedge cluster randomized trials

BACKGROUND

The Bayesian group sequential design has been applied widely in clinical studies, especially in Phase II and III studies. It allows early termination based on accumulating interim data. However, to date, there lacks development in its application to stepped-wedge cluster randomized trials, which are gaining popularity in pragmatic trials conducted by clinical and health care delivery researchers.

METHODS

We propose a Bayesian adaptive design approach for stepped-wedge cluster randomized trials, which makes adaptive decisions based on the predictive probability of declaring the intervention effective at the end of study given interim data. The Bayesian models and the algorithms for posterior inference and trial conduct are presented.

RESULTS

We present how to determine design parameters through extensive simulations to achieve desired operational characteristics. We further evaluate how various design factors, such as the number of steps, cluster size, random variability in cluster size, and correlation structures, impact trial properties, including power, type I error, and the probability of early stopping. An application example is presented.

CONCLUSION

This study presents the incorporation of Bayesian adaptive strategies into stepped-wedge cluster randomized trials design. The proposed approach provides the flexibility to stop the trial early if substantial evidence of efficacy or futility is observed, improving the flexibility and efficiency of stepped-wedge cluster randomized trials.

Sample size determination for stepped wedge cluster randomized trials in pragmatic settings

The stepped-wedge cluster randomized design has been increasingly employed by pragmatic trials in health services research. In this study, based on the GEE approach, we present closed-form sample size calculation that is applicable to both closed-cohort and cross-sectional stepped wedge trials. Importantly, the proposed method is flexible to accommodate design issues routinely encountered in pragmatic trials, such as different within- and between-subject correlation structures, irregular crossover schedules for the switch to intervention, and missing data due to repeated measurements over prolonged follow-up. The closed-form formulas allow researchers to analytically assess the impact of different design factors on sample size requirement. We also recognize the potential issue of limited numbers of clusters in pragmatic stepped wedge trials and present an adjustment approach for underestimated variance of the treatment effect. We conduct extensive simulation to assess the performance of the proposed sample size method. An application example to a real clinical trial is presented.

Age management practices toward workers aged 45 years or older: an integrative literature review

Age management practices refer to the development and implementation of workplace strategies to support and improve the health and productivity of workers aged 45 years or older. The objective of this study was to analyze the scientific evidence available to support age management practices toward older workers. An integrative review was conducted, with the following databases searched in February 2019: LILACS, MEDLINE, Web of Science, and SCOPUS. Inclusion criteria consisted of original primary studies with full-text availability, published in Portuguese, English or Spanish. Secondary studies were excluded. No restrictions were imposed on publication dates given the paucity of literature on this topic. The final sample consisted of 11 primary studies published between 2006 and 2017, which addressed the following age management practices: workplace health promotion; employment exit and transition to retirement; knowledge transfer, training and lifelong learning; career development; flexible working time practices; and occupational safety and health management. Age management practices are promising tools to promote a work environment that is adequate to the needs of older workers.

Self-reported work ability predicts health-related exit and absence from work, work participation, and death: longitudinal findings from a sample of German employees

Objective

The cohort study examined the performance of the Work Ability Index in predicting health-related exit and absence from work, work participation, and death among a sample of workers previously receiving sickness absence benefits.

Methods

Workers aged 40–54 years who received sickness absence benefits in 2012 completed the Work Ability Index in 2013. Outcomes were extracted from administrative data records covering the period until the end of 2016.

Results

Data for 2266 participants were included (mean age: 47.9 years; 54.4% women). Maximum follow-up was 43 months. In terms of work ability, 38.4% had good scores, 38.2% moderate scores, and 23.4% poor scores. Fully adjusted analyses showed an increased risk of a disability pension in workers with poor (HR = 12.98; 95% CI 5.81–28.99) and moderate Work Ability Index scores (HR = 3.17; 95% CI 1.36–7.38) compared to workers with good or excellent scores. The risk of a rehabilitation measure was also significantly increased for workers with poor and moderate scores. In addition, poor scores were prospectively associated with a longer duration of sickness absence and unemployment benefits, and fewer employment days and less income from regular employment. Those with poor Work Ability Index scores also had a significantly increased risk of premature death.

Conclusions

The Work Ability Index is a potential tool to identify individuals with previous long-term sickness absence having an increased risk of health-related exit and absence from work and poor work participation outcomes.

Electronic supplementary material

The online version of this article (10.1007/s00420-020-01608-4) contains supplementary material, which is available to authorized users.

Unshrouding the Sphere from the Clouds: Towards a Comprehensive Conceptual Framework for Sustainable Employability

Sustainable employability refers to individuals’ long-term abilities to work and remain employed. Despite its societal importance in the light of aging populations and rapidly changing skill demands, sustainable employability still requires further definition and conceptualization. As such, the present paper aims to define and conceptualize sustainable employability comprehensively by reviewing existing studies on the concept. Additionally, the paper discusses and integrates sustainable employment, sustainable work, and sustainable work ability into our broad framework of sustainable employability. The resulting conceptual framework positions sustainable employability as an inherently longitudinal multidimensional individual characteristic that is the outcome of complex interactions between individual-, work- and work environmental characteristics. This framework enables researchers to identify the employment characteristics that promote sustainable employability and thereby comprise sustainable employment. Finally, the framework links to notions of person-environment fit, and job- and organizational design to create a basis for future research on sustainable employability.

A systematic review of interventions to retain chronically ill occupationally active employees in work: can findings be transferred to cancer survivors?

Background: Interventions supporting occupationally active cancer survivors to retain work and prevent adverse work outcomes, beyond return to work, are scarce. As lessons may be learned from interventions that have been evaluated in working employees with other chronic diseases than cancer, the objective of this review was to summarize the characteristics of these interventions. Material and methods: Studies were identified through computerized PubMed, EMBASE and PsycINFO searches, without any language or year of publication restrictions. Randomized controlled trials were included if they evaluated the effectiveness of interventions to retain chronically ill occupationally active employees in work. Two authors independently extracted data from each study and assessed the risk of bias. Results: The search identified 536 unique studies, of which 18 met the inclusion criteria. All included studies had a low risk of bias. (Psycho-)educational interventions for chronically ill employees to retain work were evaluated in two studies, physical interventions in three studies, vocational/work-related interventions in five studies, and multidisciplinary interventions in eight studies. Vocational/work-related and multidisciplinary interventions, and the involvement of professional trainers, showed the most promising effects in retaining employees. However, small sample sizes may have caused imprecise effect estimates. Conclusion: Based on studies focusing on occupationally active employees with other chronic diseases than cancer, it is advised that working cancer survivors should be offered tailored interventions, by skilled trainers, to sustain their employability. Shared goal setting, with relevant stakeholders, and vocational components should be included, potentially as part of a multidisciplinary intervention.

Effectiveness and Cost-benefit Evaluation of a Comprehensive Workers' Health Surveillance Program for Sustainable Employability of Meat Processing Workers

Objective To evaluate the effectiveness of a comprehensive workers' health surveillance (WHS) program on aspects of sustainable employability and cost-benefit. Methods A cluster randomized stepped wedge trial was performed in a Dutch meat processing company from february 2012 until march 2015. In total 305 workers participated in the trial. Outcomes were retrieved during a WHS program, by multiple questionnaires, and from company registries. Primary outcomes were sickness absence, work ability, and productivity. Secondary outcomes were health, vitality, and psychosocial workload. Data were analyzed with linear and logistic multilevel models. Cost-benefit analyses from the employer's perspective were performed as well. Results Primary outcomes sickness absence (OR = 1.40), work ability (B = -0.63) and productivity (OR = 0.71) were better in the control condition. Secondary outcomes did not or minimally differ between conditions. Of the 12 secondary outcomes, the only outcome that scored better in the experimental condition was meaning of work (B = 0.18). Controlling for confounders did not or minimally change the results. However, our stepped wedge design did not enable adjustment for confounding in the last two periods of the trial. The WHS program resulted in higher costs for the employer on the short and middle term. Conclusions Primary outcomes did not improve after program implementation and secondary outcomes remained equal after implementation. The program was not cost-beneficial after 1-3 year follow-up. Main limitation that may have contributed to absence of positive effects may be program failure, because interventions were not deployed as intended.

Process Evaluation of a Workers' Health Surveillance Program for Meat Processing Workers

Objective To evaluate the implementation process of a workers' health surveillance (WHS) program in a Dutch meat processing company. Methods Workers from five plants were eligible to participate in the WHS program. The program consisted of four evaluative components and an intervention component. Qualitative and quantitative methods were used to evaluate seven process aspects. Data were gathered by interviews with stakeholders, participant questionnaires, and from registries of the company and occupational health service. Results Two recruitment strategies were used: open invitation or automatic participation. Of the 986 eligible workers, 305 participated in the program. Average reach was 53 %. Two out of five program components could not be assessed on dose delivered, dose received and fidelity. If components were assessable, 85-100 % of the components was delivered, 66-100 % of the components was received by participants, and fidelity was 100 %. Participants were satisfied with the WHS program (mean score 7.6). Contextual factors that facilitated implementation were among others societal developments and management support. Factors that formed barriers were program novelty and delayed follow-up. Conclusion The WHS program was well received by participants. Not all participants were offered the same number of program components, and not all components were performed according to protocol. Deviation from protocol is an indication of program failure and may affect program effectiveness.

Stepped wedge cluster randomised trials: a review of the statistical methodology used and available

BACKGROUND

Previous reviews have focussed on the rationale for employing the stepped wedge design (SWD), the areas of research to which the design has been applied and the general characteristics of the design. However these did not focus on the statistical methods nor addressed the appropriateness of sample size methods used.This was a review of the literature of the statistical methodology used in stepped wedge cluster randomised trials.

METHODS

Literature Review. The Medline, Embase, PsycINFO, CINAHL and Cochrane databases were searched for methodological guides and RCTs which employed the stepped wedge design.

RESULTS

This review identified 102 trials which employed the stepped wedge design compared to 37 from the most recent review by Beard et al. 2015. Forty six trials were cohort designs and 45 % (n = 46) had fewer than 10 clusters. Of the 42 articles discussing the design methodology 10 covered analysis and seven covered sample size. For cohort stepped wedge designs there was only one paper considering analysis and one considering sample size methods. Most trials employed either a GEE or mixed model approach to analysis (n = 77) but only 22 trials (22 %) estimated sample size in a way which accounted for the stepped wedge design that was subsequently used.

CONCLUSIONS

Many studies which employ the stepped wedge design have few clusters but use methods of analysis which may require more clusters for unbiased and efficient intervention effect estimates. There is the need for research on the minimum number of clusters required for both types of stepped wedge design. Researchers should distinguish in the sample size calculation between cohort and cross sectional stepped wedge designs. Further research is needed on the effect of adjusting for the potential confounding of time on the study power.

Workers' Health Surveillance in the Meat Processing Industry: Work and Health Indicators Associated with Work Ability

BACKGROUND

Workers' health surveillance (WHS) programs commonly measure a large number of indicators addressing health habits and health risks. Recently, work ability and functional capacity have been included as important risk measures in WHS. In order to address work ability appropriately, knowledge of associations with work and health measures is necessary. The objective of this study was to evaluate which of the factors measured in a WHS are independently associated with work ability in a group of meat processing workers.

METHODS

A cross-sectional study was performed in a large meat processing company in The Netherlands. Data were collected during a WHS between February 2012 and March 2014. Personal characteristics, health habits and health-risk indicators, functional capacity, and work-related factors were measured. Work ability was measured with the Work Ability Index and was used as dependent variable. Univariable and multivariable logistic regression analyses were conducted, a receiver operating characteristic curve was constructed and the area under the curve (AUC) was calculated.

RESULTS

Data sets from 230 employees were used for analyses. The average age was 53 years and the average work ability index score was 39.3. In the final multivariable model age (OR 0.94), systolic blood pressure (OR 1.03), need for recovery (OR 0.56), and overhead work capacity (OR 3.95) contributed significantly. The AUC for this model was 0.81 (95% CI 0.75-0.86).

CONCLUSION

Findings from the current study indicate that multifactorial outcomes (age, systolic blood pressure, need for recovery, and overhead work capacity) from a WHS were independently associated with work ability. These factors can be used to assess employees at risk for low work ability and might provide directions for interventions.

Stepped wedge randomised controlled trials: systematic review of studies published between 2010 and 2014

BACKGROUND

In a stepped wedge, cluster randomised trial, clusters receive the intervention at different time points, and the order in which they received it is randomised. Previous systematic reviews of stepped wedge trials have documented a steady rise in their use between 1987 and 2010, which was attributed to the design's perceived logistical and analytical advantages. However, the interventions included in these systematic reviews were often poorly reported and did not adequately describe the analysis and/or methodology used. Since 2010, a number of additional stepped wedge trials have been published. This article aims to update previous systematic reviews, and consider what interventions were tested and the rationale given for using a stepped wedge design.

METHODS

We searched PubMed, PsychINFO, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Web of Science, the Cochrane Library and the Current Controlled Trials Register for articles published between January 2010 and May 2014. We considered stepped wedge randomised controlled trials in all fields of research. We independently extracted data from retrieved articles and reviewed them. Interventions were then coded using the functions specified by the Behaviour Change Wheel, and for behaviour change techniques using a validated taxonomy.

RESULTS

Our review identified 37 stepped wedge trials, reported in 10 articles presenting trial results, one conference abstract, 21 protocol or study design articles and five trial registrations. These were mostly conducted in developed countries (n = 30), and within healthcare organisations (n = 28). A total of 33 of the interventions were educationally based, with the most commonly used behaviour change techniques being 'instruction on how to perform a behaviour' (n = 32) and 'persuasive source' (n = 25). Authors gave a wide range of reasons for the use of the stepped wedge trial design, including ethical considerations, logistical, financial and methodological. The adequacy of reporting varied across studies: many did not provide sufficient detail regarding the methodology or calculation of the required sample size.

CONCLUSIONS

The popularity of stepped wedge trials has increased since 2010, predominantly in high-income countries. However, there is a need for further guidance on their reporting and analysis.

Work-family conflicts and self-reported work ability: cross-sectional findings in women with chronic musculoskeletal disorders

Background

Under conditions of gender-specific division of paid employment and unpaid childcare and housework, rising employment of women increases the likelihood that they will be faced with work-family conflicts. As recent research indicates, such conflicts might also contribute to musculoskeletal disorders. However, research in patient samples is needed to clarify how important these conflicts are for relevant health-related measures of functioning (e.g., work ability). We therefore examined, in a sample of women with chronic musculoskeletal disorders, the indirect and direct associations between the indicators of work-family conflicts and self-reported work ability as well as whether the direct effects remained significant after adjustment for covariates.

Methods

A cross-sectional questionnaire-based study was conducted. Participants were recruited from five rehabilitation centers. Work-family conflicts were assessed by four scales referring to time- and strain-based work interference with family (WIF) and family interference with work (FIW). Self-reported work ability was measured by the Work Ability Index. A confirmatory factor analysis was performed to approve the anticipated four-factor structure of the work-family conflict measure. Direct and indirect associations between work-family conflict indicators and self-reported work ability were examined by path model analysis. Multivariate regression models were performed to calculate adjusted estimators of the direct effects of strain-based WIF and FIW on work ability.

Results

The study included 351 employed women. The confirmatory factor analysis provided support for the anticipated four-factor structure of the work-family conflict measure. The path model analysis identified direct effects of both strain-based scales on self-reported work ability. The time-based scales were indirectly associated with work ability via the strain-based scales. Adjusted regression analyses showed that a five-point increase in strain-based WIF or FIW was associated with a four- and two-point decrease in self-reported work ability, respectively. The standardized regression coefficients were β = 0.35 and β = 0.12.

Conclusions

Our findings indicate that work-family conflicts are associated with poor work ability in female patients with chronic musculoskeletal disorders. However, longitudinal research is needed to establish a causal relationship. Better compatibility of work and family life might be an environmental facilitator of better rehabilitation outcomes in female patients with musculoskeletal disorders.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-015-0515-4) contains supplementary material, which is available to authorized users.

Preventive occupational health interventions in the meat processing industry in upper-middle and high-income countries: a systematic review on their effectiveness

OBJECTIVE

To investigate the effectiveness of occupational health interventions in the meat processing industry on work and health-related outcomes.

METHODS

A systematic literature review was performed. PubMed, Embase, and The Cochrane Library were searched. Studies were included when they reported on an intervention among employees in the meat processing industry and with outcomes related to work or health. Studies were assessed on risk of bias, and data were synthesized by type of intervention.

RESULTS

A total of 13 articles reporting on two randomized controlled trials and nine non-randomized intervention studies were retrieved. Studies were categorized into three topics: ergonomics programs, skin protection, and Q fever vaccination. All studies had high risk of bias. Based on four studies, there was limited evidence for workplace health and safety programs showing reductions in musculoskeletal injury severity, reduction of lost work days, and reduction of costs and claims for several musculoskeletal disorders. There was limited evidence for added rest breaks resulting in improved productivity at the end of a workday and in reductions of perceived discomfort in various body regions at the end of the workday. One study on skin protection showed reductions of eczema prevalence, although evidence was moderate. Based on four studies, there was high-quality evidence for strong effectiveness of Q fever vaccination.

CONCLUSION

This review presents evidence for the effectiveness of a variety of workplace interventions. There was limited evidence for effectiveness of ergonomic interventions, moderate evidence of a skin protection intervention, and strong evidence for Q fever vaccination.

Topics and trends in research on non-clinical interventions aimed at preventing prolonged work disability in workers compensated for work-related musculoskeletal disorders (WRMSDs): a systematic, comprehensive literature review

PURPOSE

This study sought to provide an overview of the main topics and trends in contemporary research on successful non-clinical interventions for preventing prolonged work disability in workers compensated for work-related musculoskeletal disorders (WRMSDs).

METHODS

A systematic electronic search (English and French) was performed in ten scientific databases using keywords and descriptors. After screening the identified titles and abstracts using specific sets of criteria, categorical and thematic analyses were performed on the retained articles.

RESULTS

Five main topics appear to dominate the research: (1) risk factors and determinants; (2) effectiveness of interventions (programmes, specific components, strategies and policies); (3) viewpoints, experiences and perceptions of specific actors involved in the intervention process; (4) compensation issues; and (5) measurement issues. A currently widespread trend is early screening to identify risks factors for appropriate intervention and multidisciplinary, multimodal approaches. Morover, workplace-related psychosocial and ergonomic factors are considered vital to the success and sustainability of return-to-work (RTW) interventions. Finally, involving workplace actors, and more specifically, affected workers, in the RTW process appears to be a powerful force in improving the chances of moving workers away from disabled status.

CONCLUSIONS

The findings of this literature review provide with information about the main topics and trends in research on rehabilitation interventions, revealing some successful modalities of intervention aimed at preventing prolonged work disability.

IMPLICATIONS FOR REHABILITATION

Successful intervention for preventing prolonged work disability in workers compensated for WRMSDs address workplace issues: physical and psychosocial demands at work, ability of the workers to fill these demands, work organization and support of the worker, and worker' beliefs and attitudes related to work. Successful intervention promotes collaboration, coordination between all actors and stakeholders involved in the process of rehabilitation. Strategies able to mobilize the employees, employers, insurers and health care providers are still needed to be implemented.