Identification of potentially obsolete technologies is a fundamental part of this guide. Without a rigorous and reliable detection system it would not be possible for the more important ones to be prioritised and, as a result, this could lead to appraisal of obsolete technologies of scant interest in terms of the real benefit with their possible withdrawal from clinical practice.
In order to locate these technologies, it is essential to have data sources and search systems which are sensitive and yet specific, thereby fostering efficiency, in the sense that this enables interested parties to locate potential obsolete technologies for subsequent evaluation with the minimum possible effort.