381,523 papers found

A structured review of existing literature was undertaken to provide an objective evaluation of the validity of cardiac output measurement by thoracic impedance. Relevant studies were obtained from journals, advertising literature, and N.A.S.A. contract publications, using MEDLINE retrieval and references from other st…

Several clinical studies have evaluated the efficacy and safety of LMWH in the prevention of postoperative thromboembolic complications. We subjected 42 studies to a statistical meta-analysis in order to evaluate the efficacy of different prophylactic regimens compared with LMWH prophylaxis. In general surgery LMWH was…

BACKGROUND: Meta-analysis is intended as a tool for the objective synthesis of evidence across a literature, in order to obtain the best evidence as to whether or not an association or effect is robust. However, as the use of meta-analysis has proliferated it has become increasingly clear that the results of a meta-ana…

OBJECTIVE: To use meta-analysis to estimate the benefits of drug treatment to lower cholesterol levels in the primary and secondary prevention of coronary heart disease (CHD) events. DATA SOURCES: MEDLINE search from 1967 to 1990; bibliographies of review articles. STUDY SELECTION: Nine trials met the entry criteria:…

A P value, or the magnitude or direction of results can influence decisions about whether, when, and how research findings are disseminated. Regardless of whether an entire study or a particular study result is unavailable because investigators considered the results to be unfavorable, bias in a meta-analysis may occur…

Variance between studies in a meta-analysis will exist. This heterogeneity may be of clinical, methodological or statistical origin. The last of these is quantified by the I(2) -statistic. We investigated, using simulated studies, the accuracy of I(2) in the assessment of heterogeneity and the effects of heterogeneity…

Heparin treatment of venous thromboembolic disease has been validated since 1960. Nevertheless no study was sufficient to determine an optimal therapeutic schedule between sub-cutaneous (SC) unfractionated heparin (UFH), intravenous (IV) UFH and low molecular weight heparin (LMWH). One meta-analysis showed a significan…

BACKGROUND: This network meta-analysis comprehensively compared the accuracy of the currently commonly used venous thromboembolism (VTE) assessment scale for screening peripherally inserted central catheter-associated VTE. METHODS: We conducted a comprehensive literature search to obtain relevant studies on diagnostic…

The aim of this research was to study the prevalence of infection by the human immunodeficiency virus (HIV) among the Spanish population. Due to the lack of available data we have applied meta-analysis techniques. We analyzed 67 original publications on this field appeared between 1985 and 1989. The prevalence of the i…

Lyme borreliosis is currently suspected to be capable of mimicking nearly all known neurologic symptoms and disease entities. The goal of our study is to define the associated anamnestic, clinical and laboratory findings in aseptic meningitis and Lyme borreliosis in childhood by a meta-analysis of recent literature and…

OBJECTIVES: Temporal trends in comparative meta-analyses of interventions are well-recognized in the medical literature. For studies of diagnostic test accuracy (DTA), evidence of temporal trends is growing and the importance of assessing and reporting them has been highlighted in recent guidelines on postmarket survei…

OBJECTIVE: To evaluate the correlation of Ureaplasma urealyticum (Uu) and Chlamydia trachomatis (Ct) infections with male sterility. METHODS: Data from CBMA and CNKI were searched and studies were made for the correlation of Uu and Ct infections with male sterility by retrieval strategy worked out according to the Col…

BACKGROUND: Multivariate meta-analysis (MVMA) jointly synthesizes effects for multiple correlated outcomes. The MVMA model is potentially more difficult and time-consuming to apply than univariate models, so if its use makes little difference to parameter estimates, it could be argued that it is redundant. METHODS: We…