Cohort profile: workers' compensation in a changing Australian labour market: the return to work (RTW) study

Cannabis use among workers with work-related injuries and illnesses: results from a cross-sectional study of workers' compensation claimants in Ontario, Canada

OBJECTIVES

Little is known about how workers use cannabis following a work-related injury/illness, including whether they receive clinical guidance. The objective was to compare characteristics of workers using and not using cannabis after a work-related injury/illness and describe use patterns.

DESIGN

Cross-sectional study.

SETTING AND PARTICIPANTS

Workers who experienced a work-related physical injury/illness resulting in one or more days of lost time compensated by the workers' compensation authority in Ontario, Canada (n=1196).

METHODS

Participants were interviewed 18 or 36 months after their injury/illness. Participants were asked about their past-year cannabis use, including whether use was for the treatment of their work-related condition. Sociodemographic, work and health characteristics were compared across cannabis groups: no past-year use; use for the work-related condition; use unrelated to the work-related condition. Cannabis use reasons, patterns, perceived impact and healthcare provider engagement were described.

RESULTS

In total, 27.4% of the sample reported using cannabis (14.1% for their work-related condition). Workers using cannabis for their condition were less likely to be working (58.0%) and more likely to have quite a bit/extreme pain interference (48.5%), psychological distress (26.0%) and sleep problems most/all the time (62.1%) compared with those not using cannabis (74.3%, 26.3%, 12.0% and 38.0%, respectively) and those using cannabis for other reasons (74.2%, 19.5%, 12.0% and 37.1%, respectively) (all p<0.0001). No significant differences were observed in medical authorisations for use among those using cannabis for their condition (20.4%) or unrelated to their condition (15.7%) (p=0.3021). Healthcare provider guidance was more common among those using cannabis for their condition (32.7%) compared with those using for other reasons (17.1%) (p=0.0024); however, two-thirds of this group did not receive guidance.

CONCLUSIONS

Cannabis may be used to manage the consequences of work-related injuries/illnesses, yet most do not receive clinical guidance. It is important that healthcare providers speak with injured workers about their cannabis use.

Cohort profile: the Ontario Life After Workplace Injury Study (OLAWIS)

PURPOSE

The substantial economic burden of work-related injury and illness, borne by workers, employers and social security programmes, is primarily attributed to the durations of work disability among workers whose recovery requires a period of absence from work, with the majority of costs arising from the minority of workers with the longest duration absences. The objective of the Ontario Life After Workplace Injury Study is to describe the long-term health and labour market outcomes of workers disabled by work injury or illness after they are no longer receiving benefits or services from the work disability insurance authority.

PARTICIPANTS

Workers disabled by a work-related injury or illness were recruited from a sample frame of disability benefit claimants with oversampling of claimants with longer benefit durations. Characteristics of workers, their employers and claimant benefits were obtained from baseline administrative data. Interviews completed at 18 months post injury (T1) and to be completed at 36 months (T2) measure return-to-work and work status; income; physical and mental health; case manager and healthcare provider interactions and employer accommodations supporting return-to-work and sociodemographic characteristics. Of eligible claimants, 40% (1132) participated in the T1 interview, with 96% consenting to participate in the T2 interview.

FINDINGS TO DATE

Preliminary descriptive analyses of T1 data have been completed. The median age was 50 years and 56% were male. At 18 months following injury, 61% were employed by their at-injury employer, 16% had changed employment and 23% were not working. Past-year prescription opioid use was prevalent (34%), as was past-year cannabis use (31%). Longer duration claimants had poorer function, recovery and health and more adverse labour market outcomes.

FUTURE PLANS

Multivariate analyses to identify modifiable predictors of adverse health and labour market outcomes and a follow-up survey of 96% of participants consenting to follow-up at 36 months are planned.

Age Differences in Return-to-Work Following Injury: Understanding the Role of Age Dimensions Across Longitudinal Follow-up

OBJECTIVES

To examine the overall association between chronological age and return-to-work (RTW), and understand if existing data could be used to better understand the role of age-related dimensions (functional, psychosocial, organizational, life-stage) in explaining these associations.

METHODS

We used survey data from a prospective cohort of injured workers in Victoria, Australia. Path models examined the relationship between chronological age and RTW, and the proportion mediated via age dimensions.

RESULTS

Older chronological age was associated with non-RTW, although the pattern was not observed consistently across follow-up surveys. A proportion of the overall relationship between chronological age and non-RTW was explained by functional and life-stage age and RTW status at previous time points.

CONCLUSIONS

Findings underscore the importance of moving beyond age measured only in chronological years, towards more complex conceptual and analytical models that recognize age as a multidimensional construct.

Are there differences in the return to work process for work-related psychological and musculoskeletal injuries? A longitudinal path analysis

PURPOSE

To examine differences in the return to work (RTW) process for workers' compensation claimants with psychological injuries compared to those with musculoskeletal (MSK) injuries.

METHODS

We collected data from 869 workers' compensation claimants in Victoria, Australia, at three time points over a 12-month period (21% with psychological injury claims). RTW was assessed through self-report. Potential mediators were identified at the personal, health-care provider, workplace and system levels. The relationships between injury type, mediating factors and RTW were assessed using path analysis, with adjustment for confounders through inverse probability weighting.

RESULTS

We observed better RTW outcomes for claimants with MSK injuries (compared to those with psychological injuries) at T1 and T2, but not at T3. We also observed differences between psychological injuries and MSK injuries and all but two of the mediating factors examined. These differences, in particular related to supervisor response to injury, consultative RTW planning and offers of accommodation, as well as differences in mental health symptoms, explained approximately two-thirds of differences in RTW between injury types at T1. Differences in RTW at T2 were explained by mediating factors, and differences in RTW at T1.

CONCLUSION

Claimants with work-related psychological injuries experience a variety of challenges in RTW compared to those with MSK injuries. While treating and preventing further exacerbation of psychological symptoms should remain an important part of the rehabilitation process, other modifiable factors, in particular supervisor response to injury and consultative RTW planning and modified duties, should be prioritised to reduce inequalities in RTW across injury types.

How Does Perceived Fairness in the Workers' Compensation Claims Process Affect Mental Health Following a Workplace Injury?

Purpose Mental health concerns are common after a workplace injury, particularly amongst those making a compensation claim. Yet there is a lack of research exploring the effect of modifiable elements of the return-to-work process on mental health. The aim of this study is to examine the impact of perceived injustice in the interactions between claim agents and claimants on mental health symptoms in the 12-month following a musculoskeletal (MSK) workplace injury. Methods A cohort of 585 workers compensation claimants in Victoria, Australia were interviewed three times over a 12-month period following a workplace MSK injury. Perceptions of informational and interpersonal justice in claim agent interactions were measured at baseline, and the Kessler Psychological Distress (K6) scale was administered as a measure of mental health at all three timepoints. Path analyses were performed to examine the direct and indirect effects of perceived justice at baseline on concurrent and future mental health, after accounting for confounding variables. Results Each 1-unit increase in perceptions of informational and interpersonal justice, indicating poorer experiences, was associated with an absolute increase of 0.16 and 0.18 in respective K6 mental health score at baseline, indicating poorer mental health on a 5-point scale. In addition, perceived justice indirectly impacted mental health at 6-month and 12-month, through sustained negative impact from baseline as well as increased risk of disagreements between the claim agent and claimant. Conclusions This finding has highlighted the importance of perceived justice in claim agent interactions with claimants in relation to mental health following a work-related MSK injury.

Prevalence of serious mental illness and mental health service use after a workplace injury: a longitudinal study of workers’ compensation claimants in Victoria, Australia

Objectives

Serious mental illness is common among those who have experienced a physical workplace injury, yet little is known about mental health service use in this population. This study aims to estimate the proportion of the workplace musculoskeletal injury population experiencing a mental illness, the proportion who access mental health services through the workers’ compensation system and the factors associated with likelihood of accessing services.

Methods

A longitudinal cohort study was conducted with a random sample of 615 workers’ compensation claimants followed over three survey waves between June 2014 and July 2015. The primary outcome was receiving any type of mental health service use during this period, as determined by linking survey responses to administrative compensation system records for the 18 months after initial interview.

Results

Of 181 (29.4%) participants who met the case definition for a serious mental illness at one or more of the three interviews, 75 (41.4%) accessed a mental health service during the 18-month observation period. Older age (OR=0.96, 95% CI 0.93 to 0.99) and achieving sustained return to work (OR=0.27, 95% CI 0.11 to 0.69) were associated with reduced odds of mental health service use. Although not significant, being born in Australia was associated with an increased odds of service use (OR=2.23, 95% CI 0.97 to 5.10).

Conclusions

The proportion of injured workers with musculoskeletal conditions experiencing mental illness is high, yet the proportion receiving mental health services is low. More work is needed to explore factors associated with mental health service use in this population, including the effect of returning to work.

Differences Over Time in the Prognostic Effect of Return to Work Self-Efficacy on a Sustained Return to Work

Purpose This study investigated the association between return to work self-efficacy (RTW-SE) and sustained return to work (RTW) at two different time points, over a 12-month period. The primary objective of the study was to examine if the relationship between RTW-SE and a sustained RTW changed over the RTW timeline. Methods This study used survey responses from a longitudinal cohort of n = 410 workers' compensation claimants with either an upper-body musculoskeletal injury or a psychological injury. A path analysis tested the associations between RTW-SE and a sustained RTW at two time-points. A Wald χ² test compared nested models to determine if the association changed over time. Results RTW-SE measured at time- point 1 (T1) was associated with a sustained RTW at time-point two (T2) (β = 0.24, P < 0.05) but no association was found between RTW-SE at T2 and a sustained RTW at time-point three (T3) (β = 0.017, n.s.). Model comparisons revealed significant differences in the associations between RTW-SE and a sustained RTW, with the relationship being stronger in the early phase of RTW compared to the latter phase (χ² = 5.002, p = 0.03). Conclusions The results indicate that RTW-SE at 4-6 months post-injury is important for a sustained RTW 6-months later although RTW-SE at 10-12 months post-injury had a negligible association over the same duration. Further research should investigate whether these findings generalize to other populations and what factors other than RTW-SE are associated with RTW in the later stages of the RTW process.

Health Care Provider Communication and the Duration of Time Loss Among Injured Workers: A Prospective Cohort Study

BACKGROUND

In addition to providing injured workers with biomedical treatment, health care providers (HCPs) can promote return to work (RTW) through various communications.

OBJECTIVES

To test the effect of several types of HCP communications on time loss following injury.

RESEARCH DESIGN

The authors analyzed survey and administrative claims data from a total of 730 injured workers in Victoria, Australia. Survey responses were collected around 5 months postinjury and provided data on HCP communication and confounders. Administrative claim records provided data on compensated time loss postsurvey. The authors conducted multivariate zero-inflated Poisson regressions to determine both the odds of having future time loss and its duration.

MEASURES

Types of HCP communications included providing an estimated RTW date, discussing types of activities the injured worker could do or ways to prevent a recurrence, and contacting other RTW stakeholders. Each was measured in isolation as well as modified by a low-stress experience with the HCP. Time loss was the count of cumulative compensated work absence in weeks, accrued postsurvey.

RESULTS

RTW dates reduced the odds of future time loss [odds ratio, 0.26; 95% confidence interval (CI), 0.09-0.82] regardless of the stressfulness of the experience. Communications that predicted shorter durations of time loss only did so with low-stress experiences: RTW date [incidence rate ratio (IRR), 0.56; 95% CI, 0.50-0.63], stakeholder contact (IRR, 0.78; 95% CI, 0.70-0.87), and prevention discussions (IRR, 0.87; 95% CI, 0.78-0.98).

CONCLUSIONS

HCPs may reduce time loss through several types of communication, particularly when stress is minimized. RTW dates had the largest and most robust effect.