Meta-analysis of screening data: a survey of the literature.

Meta-analysis has become a popular technique in many areas of biomedical research. While there have been a number of studies and commentaries on the use of meta-analyses and systematic reviews of clinical trials of therapy, little is known about the use of meta-analysis techniques for the evaluation of screening data. This paper presents the first systematic survey of meta-analyses of screening, with an assessment of their methodologic quality and their statistical methods. Our findings show that meta-analysis has not often been used in this area as yet, and that published meta-analyses of screening are often deficient in their reporting of methodology. A brief examination of the evaluative methods of several policy-making groups reveals that they did not routinely use formal quantitative meta-analyses of screening data, at least until 1997. There is considerable potential for meta-analyses of this kind, but improvement in methodological standards will be required to obtain valid conclusions. Copyright 1999 John Wiley & Sons, Ltd.