The cost effectiveness of occupational health interventions: preventing occupational back pain

Occupational back pain exacts a toll on society with concomitant economic losses; it is imperative to evaluate the cost-effectiveness of interventions to reduce the relevant ergonomic stressors at work. This study estimates and evaluates the average and incremental cost-effectiveness ratios (CERs) of specific interventions for the prevention of occupationally induced back pain for the World Health Organization (WHO) defined subregions of the world.

Four back-pain interventions were selected from the literature: training (T), engineering controls (EC), engineering controls and training (EC&T), and a comprehensive full ergonomics program (EP) for evaluation. A simulation model for a 100-year time horizon, developed by the WHO CHOICE initiative project was used to estimate the effectiveness of the interventions in healthy year equivalents. The intervention costs were adjusted for all WHO subregions.

In all of the subregions, training was the most cost-effective with CERs varying from 74 dollars per healthy life years gained in the subregion comprising of Egypt, Iraq, Morocco, Yemen (EMROD) to approximately 567 dollars in the subregion covering Canada and the United States (AMROA). Training is considered to be very cost-effective and would be the first choice option where resources are scarce. However, the overall effectiveness of training is low. Although other interventions such as engineering controls and total ergonomic interventions are relatively more expensive, the addition to health outcome through these interventions is much higher. The difference in the CERs for training and other engineering controls and full ergonomic interventions is relatively small for most of the industrialized regions of the world. It is clear from the ranked CERs and incremental CERs over the different subregions that in most of the industrialized regions of the world additional resources, if they become available, should go straight to the full ergonomics program.

The model results based on CERs show that worker training is a low cost, feasible first step toward reducing back pain/injury incidence. However, all of the average CERs for the different interventions, for each of the regions, fall well within their GDP per capita estimates [World Bank, 2001]. According to the WHO Commission on Macroeconomics and Health any intervention that costs less than three times GDP per capita for saving a healthy year equivalent should be considered worthwhile and good value for money [WHO, 2002]. Given this criterion, the engineering controls interventions as well as the full ergonomics program look very cost effective for all of the WHO subregions.