VEGF is a frequently studied angiogenic factor in ovarian cancer (OC), and is considered to have an important role in the progression of OC. However, its diagnostic value has not been widely accepted because the conclusions are inconsistent and even conflicting. Therefore, we performed a meta-analysis to evaluate the diagnostic value of VEGF in OC. A systematic literature search was conducted u...

BACKGROUND The Quality of Reporting of Meta-analyses (QUOROM) statement provides guidance for improving the quality of reporting of systematic reviews and meta-analyses. To make the process of study selection transparent it recommends "a flow diagram providing information about the number of RCTs identified, included, and excluded and the reasons for excluding them". We undertook an empirical s...

Multi-level modelling is a technology that promotes an incremental refinement of meta-models in successive meta-levels. This enables a flexible way of modelling, which results in simpler and more intensional models in some scenarios. In this context, integrity constraints can be placed at any meta-level, and need to indicate at which meta-level below they should hold. This requires a very caref...

OBJECTIVE To determine the effectiveness of acupuncture for smoking cessation and to examine whether any individual aspect of trials is associated with an effect. DATA SOURCES All randomised controlled trials of acupuncture for smoking cessation that were listed in computerised databases or reference lists of relevant articles. STUDY SELECTION All randomised single-blind studies that compar...

OBJECTIVE To assess the influence of trial sample size on treatment effect estimates within meta-analyses. DESIGN Meta-epidemiological study. DATA SOURCES 93 meta-analyses (735 randomised controlled trials) assessing therapeutic interventions with binary outcomes, published in the 10 leading journals of each medical subject category of the Journal Citation Reports or in the Cochrane Databas...

OBJECTIVE The objective of this study was to assess the association between women with endometriosis and risk of preterm birth. METHODS Two reviewers independently determined all prospective cohort study, retrospective cohort study, large population based cohort study, retrospective secondary analysis, and double blinded, multicentric, observational and cohort study, placebo-controlled, rando...

Alcohol drinking increases the risk of several types of cancer, but studies of the relation between alcohol and lung cancer risk are complicated by smoking. The authors carried out meta-analyses for four study designs and conducted sensitivity analyses to assess the results. Pooled smoking-unadjusted relative risks (RRs) for brewery workers and alcoholics were 1.17 (95% confidence interval (CI)...

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT Several comparative measures (ratios, differences, or the number needed to treat) are used to express the effect of a drug or another intervention. These measures can vary in the way they are affected by the background risk measured from the reference group. WHAT THIS STUDY ADDS This paper reviews the formulation, interpretation and limitations of meas...

BACKGROUND The incidence of surgical site infection (SSI) across surgical procedures, specialties, and conditions is reported to vary from 0.1% to 50%. Operative duration is often cited as an independent and potentially modifiable risk factor for SSI. The objective of this systematic review was to provide an in-depth understanding of the relation between operating time and SSI. PATIENTS AND M...

Inspired by our exploration of the applicability of automated question answering (QA) technology to the task of business intelligence and general design science principle, we advocate a meta approach to the QA (fact seeking) applications since it does not rely on a single system and may provide the necessary accuracy and responsiveness. We present our prototype of a fact seeking meta engine, th...