Economic evaluations of occupational health interventions: current practices and methodological challenges

In the European Union, 8% of the workforce report work-related health problems. This results in 7.1 million disability adjusted life years, representing an economic burden of 476 billion euros annually. Thus, the workplace is an influential factor regarding health, and at the same time, a promising context to promote health. The goal of occupational health management (OHM) is to optimize the ratio of job demands to job resources. Especially interventions that are beyond the legally required minimum depend significantly on the employer’s goodwill.
Limited budgets and competing priorities raise the question of whether there are objective benefits in making workers’ health a priority. Specifically, decision makers want to know if there is a financial benefit in investing scarce resources in OHM. By analyzing the incrementalcosts and benefits of an OHM intervention, economic evaluations (EEs) can provide decision makers with important insights into which stakeholders benefit from improved workers’ health and to what magnitude, and how the cost-effectiveness of an OHM intervention compares to an alternative intervention. However, the generalizability of the findings of such
EEs is limited because they are highly dependent on national insurance systems, labor laws or other local regulations.
The first study, entitled “Cost-effectiveness and cost-benefit of worksite health promotion programs in Europe: a systematic review”, aimed to systematically summarize EEs of OHM interventions with a focus on Europe. Thirty-nine articles were analyzed, of which a large proportion showed considerable methodological shortcomings. Nine out of 21 cost-benefit analyses reported a financial benefit and 12 out of 31 cost-effectiveness analyses concluded that the intervention was cost-effective. Across all studies, productivity loss accounted for more than 85% of the total costs. Different perspectives for the EE were considered and even
with the same perspective, costs were treated heterogeneously. This made a meaningful comparison of the included EEs impossible.
The aim of the second study, entitled “Health economic evaluations of interventions to increase physical activity and decrease sedentary behavior at the workplace: a systematic review”, was therefore to synthesize EEs of one specific OHM intervention and to present their findings in a comparable way. For this reason, the effects from 18 studies were standardized (Hedges’ g), all costs were converted into 2017 Belgium euros, all economic metrics were recalculated using consistent formulae and all metrics were benefit adjusted (i.e. consistent cost categories were used per perspective). The effects of worksite physical activity interventions were generally small, potentially due to low participation rates within the included studies. Due to small sample sizes, costs were subject to substantial uncertainty in most EEs. Furthermore, there was a significant negative relationship between the methodological quality of the EEs and their reported return on investment.
In the third study, the knowledge gained about EEs in the field of OHM from the two systematic literature reviews was applied in the form of a trial-based EE entitled “Health Economic Evaluation of an Influenza Vaccination Program to Prevent Sick Leave in Employees - A Prospective Cohort Study”. The incidence rate of influenza-like illness of VUB employees who participated in the voluntary influenza vaccination program (n = 173) was compared with the rate of influenza-like illness of unvaccinated VUB employees (n = 238). A cost-benefit analysis from the employer’s perspective and a cost-effectiveness analysis from
the societal perspective were performed. In the base scenario, the influenza vaccination program was less effective and more expensive, and thus neither cost-effective nor costbeneficial.
Lack of randomization may have caused selection and allocation bias, which is why modelling techniques were used to apply published estimates of vaccination effectiveness. In this scenario, the influenza vaccination program became dominant and thus cost-beneficial.

In the course of this PhD track and in particular due to the surprising results of the third study, important questions arose regarding EEs in the context of OHM. In the fourth study with the title “What are the economic dimensions of occupational health? A qualitative crosscompany study”, OHM specialists were confronted with these questions. Thirteen semistructured interviews were performed, and the transcripts were analyzed using a mix of inductive and deductive content analysis. Five main themes emerged: understanding of OHM,
costs, benefits, environmental aspects, and evaluation of OHM. Participants perceived costs and benefits of OHM significantly different from how they are represented in current EEs. In particular, the OHM specialists pointed out intangible benefits that they consider particularly relevant. Furthermore, managers deemed (randomized) controlled studies unrealistic and inadequate for the field of OHM.