Epidemiology and oral function associated with tooth loss and prosthetic dental restorations. Consensus report of Working Group I

The method used by the working group was an iterative process based upon literature reviews of relevant publications by a working group of rapporteurs. The review papers were written and circulated before the conference and served as basis of discussion. Each paper was subject to a detailed collective analysis and modified and amended on the basis of the work group's discussions and referenced to additional relevant literature where appropriate. The group assessed the levels of evidence for the statements made in the supporting documentation and recognised that it was necessary to adopt a compromise between acceptance of the lowest level of evidence, resulting in the largest body of material, and the highest level which produced valuable but limited evidence. Where the objectives were not concerning an intervention, an RCT study design was not applicable and no focussed question could be formulated. Rather cross-sectional and repeated cross-sectional, as well as longitudinal cohort studies, were usually the evidence available.