BACKGROUND The inclusion of only a subset of all available evidence in a meta-analysis may introduce biases and threaten its validity; this is particularly likely if the subset of included studies differ from those not included, which may be the case for published and grey literature (unpublished studies, with limited distribution). We set out to examine whether exclusion of grey literature, co...

PURPOSE To assess the overall quality of published urological meta-analyses and identify predictive factors for high quality. MATERIALS AND METHODS We systematically searched PubMed to identify meta-analyses published from January 1st, 2011 to December 31st, 2015 in 10 predetermined major paper-based urology journals. The characteristics of the included meta-analyses were collected, and their...

Phosphorus (P) fertilizer recommendations in most European countries are based on plant-available soil P contents and long-term field experiments. Site-specific conditions are often neglected, resulting in excessive P fertilizer applications. P fertilization experiments including relevant site and soil parameters were evaluated in order to analyze the yield response. The database comprises abou...

BACKGROUND Although psychoses and ethnicity are well researched, the importance of culture, race and ethnicity has been overlooked in Personality Disorders (PD) research. This study aimed to review the published literature on ethnic variations of prevalence, aetiology and treatment of PD. METHOD A systematic review of studies of PD and race, culture and ethnicity including a narrative synthes...

The hierarchy of evidence based medicine postulates that systematic reviews of homogenous randomized trials represent one of the uppermost levels of clinical evidence. Indeed, the current overwhelming role of systematic reviews, meta-analyses and meta-regression analyses in evidence based heath care calls for a thorough knowledge of the pros and cons of these study designs, even for the busy cl...

background: we are living in an era in which different branches of science are growing very rapidly. therefore, retrieving and summarizing all new valid findings on a specific subject is one of the most important priorities of scientists. the aim of the present article is to categorize different review studies within the health domain based on their approach to retrieving and summarizing origin...

helicobacter pylori infection is a common health problem related to many gastrointestinal disorders. this study aims to estimate the total and age specific prevalence of helicobacter pylori infection in iran. we systematically reviewed all national and international databases and finally identified 21 studies were eligible for meta-analysis. each of them were assigned a quality score using stro...

background: the aim of the study was assessment of defaults and conducted meta-analysis of the efficacy of single-dose oral albendazole against t. trichiura infection. methods: we searched pubmed, isi web of science, science direct, the cochrane central register of controlled trials, and who library databases between 1983 and 2014. data from 13 clinical trial ar­ticles were used. each article w...