Systematic reviews to evaluate diagnostic tests.

Diagnostic testing and screening is a critical part of the clinical process because inappropriate diagnostic strategies put patients at risk and entail a serious waste of resources. It is being increasingly recognised that absence of clear summaries of individual research studies on the repeatability, accuracy and impact of tests, which are often scattered across many different journals, is a major impediment. Just as the need to develop means to systematically review research assessing the effectiveness of treatments has been pursued over the last decade, so more recently attention has focused on how research on diagnostic tests might also be systematically reviewed. These reviews present a huge methodological challenge. This paper describes the use of a systematic approach to collation, appraisal and synthesis of information contained in the primary literature about accuracy of diagnostic strategies.