• Epidemiology
• hygiene / occupational hygiene
• occupational health practice
• toxicology
• health services research

In this issue of the Journal, we are publishing a pair of commentaries offering opposing views of a proposal that observational epidemiologic studies and their protocols should be registered in advance.1 2 The proposal, which was put forward at a 2009 workshop sponsored by the European Centre for Ecotoxicology and Toxicology of Chemicals (an organisation supported by the chemical industry), posits that pre-registration would lead to better science by enhancing the transparency of research and reducing publication bias.3 The workshop report also called on editors of medical journals to promote the registration of observational studies with their authors and readers—a suggestion quickly taken up by The Lancet and the BMJ.4 5

Despite the endorsement of our sister journal (the BMJ), OEM does not require or encourage the registration of observational studies. We believe that such a requirement would not improve the quality of epidemiologic research and could instead be detrimental. In this editorial, we explain the reasoning behind this position.

The suggestion that observational studies should be registered borrows from a …