How “Intervention Research” Could Contribute To Knowledge On Musculoskeletal Disorders Prevention?

International audienceIn 2004, at Zurich PREMUS Congress, we present the results of an ergonomic intervention, demonstrating the possibility of achieving improvements in terms of working conditions and productivity. Only one question was asked: "did you have a control group?".Here we wanted to discuss to discuss the benefits of alternative approaches to intervention by research when RCT is impossible to implement or too costly (Shadish and al., 2002). We have reviewed scientific publications on this issue.Most of the studies based on RCT approach evaluate simple interventions that focus on one aspect of work situation, with a large number of workers. These workers are in very different work situations but their number can statistically compensate for these variabilities. We also know that MSDs are multifactorial diseases, so that effective prevention requires action on a variety of constraints. The intervention approaches needed are inevitably complex and involve changes of workstation, work organisation, and the actors themselves (training in job analysis, understanding of various issues related to design, knowledge of many other work situations and strategic issues for work situations concerned). They often involve a small number of workers. Understanding the specific contexts and different constraints is inconsistent with the possibility of identifying comparable workers for a statistical approach.Intervention Research is a qualitative approach, based on an accurate description of the results, the process of intervention and its context. Monitoring of symptoms does not seem sufficient to assess the performance of the intervention. Future studies should help clarify the nature of different indicators relevant to the work situation changes (workstation, work organisation, subjective experience of work). The description of the precise course of action is another important issue. In current publications, data are often very limited and does not allow readers to accurately assess the resources involved, which led to obtaining the results highlighted. Finally, the context of the intervention must not only be accurately described, but also categorised to enable those involved in prevention to assess the proximity or distance with their own contexts of action.The "intervention research" orientation is essential for prevention since it is evaluating complex actions in specific contexts, corresponding to situations with which prevention specialists are struggling. The usefulness of scientific literature on intervention seems required several conditions. One intervention can contribute to knowledge if it is sufficiently described and if discussion can examine previous models of action (Yin, 1990)