Abstract

Epidemiology is largely a practical discipline whose findings are used to inform health policy and clinical practice. Occupational epidemiology should address important and tractable questions, generating new information with the potential to influence decisions, even where policy makers encounter strong competing opinions and interests. Priorities for research should include:

1. Exposures in the workplace which may contribute importantly to the burden of illness at population level, but where uncertainty remains about causation or levels of risk (e.g. shift work and breast cancer, chronic kidney disease in sugar cane workers in Central America and parts of Asia).

2. Exposures which although not widespread, could carry a high attributable risk in individual workers. A past example would be haemangiosarcoma of the liver in VCM workers, a contemporary example hypersensitivity pneumonitis in those exposed to metal working fluids (MWF), probably attributable to Mycobacterial infection of MWF.

3. Studies to evaluate the effectiveness of interventions. Such research, while difficult and expensive, can provide critical evidence about both causation and the process of prevention. The challenge is to apply limited resources most efficiently through optimal choice of study questions and methods (randomised controlled trials are not always the best approach).

4. Descriptive epidemiology, both to identify possible unrecognised hazards (including from new technologies), and to check that known hazards are being adequately controlled.

At the same time, it is important to recognise where further research is not needed. In developing countries, studies on affordable methods of reducing hazardous exposures may be more useful than investigations to confirm risks that are already well known.