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Journal of Behavioral Addictions
Authors: Manuel Alcaraz-Ibáñez, Adrian Paterna, Álvaro Sicilia, and Mark D. Griffiths

approach that could contribute to overcoming some of these limitations and, by extension, to a better understanding of the relationship between MEB and ED is meta-analysis. By combining data from a series of studies, meta-analytic techniques allow for

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Species richness, resource availability, and disturbance are the primary factors considered in assessing the invasibility of plant communities. Nonetheless, the density of individuals in a community is a common and easy trait to measure. The ecological significance of the density of both native and invasive tree species was assessed using a systematic review and formal meta-analysis. The densities of recipient communities and invasive exotic tree species in novel ranges were identified in the published literature. In addition, we compared by means of a meta-analysis: (i) densities of invasive versus native species in invaded communities; (ii) densities of native species in invaded versus uninvaded communities; and (iii) densities of invasive species along distance gradients from initial locus of invasion. Invasive trees were found at higher densities than native species in recipient communities. Invasions by woody species were also recorded in communities with relatively low densities of natives suggesting that (i) low density forests may be more susceptible to invasion and/or (ii) density of the recipient community may be reduced during the invasion process. In addition, comparison of native species densities between invaded and uninvaded stands from the same community suggests that invasive trees negatively affect density of native trees once established. Therefore, the widely reported low density and often richness of native plants in invaded communities cannot be directly linked to ecosystem susceptibility to invasion without considering concomitant impacts. These findings suggest that density is a key preliminary determinant or factor which should be considered when assessing tree invasion dynamics.

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The objectives of the study were twofold, i.e. to evaluate methodological approaches of analyzed papers and to identify, cluster, and classify barriers to HACCP system implementation using meta-analysis as methodological tool. Hazard Analysis and Critical Control Point (HACCP) is a science-based system of risk management designed to control food safety. HACCP is based on seven basic principles, which present an important tool in combating food borne disease. Articles for analysis were initially selected in the major on-line database for the field, namely “Food Science and Technology Abstract”. Other databases were also used, including Commonwealth Agricultural Bureau and Co-operative Online Bibliographic System and Services. Selection was based on scientific excellence of the journal as well as on the method applied within the study. Main keywords to select appropriate scientific and technical articles were “HACCP”, “barrier” and “implementation”. Main results of methodological inquiry revealed that the most frequent methods used in scientific articles were quantitative ones. Among qualitative methods, the “narrative interview” was used most often, while among quantitative methods survey was used most frequently. Whereas narrative interview enables in-depth analysis of implicit role of individual actor in HACCP system, survey methods estimate frequency distributions of particular behaviours or attitudes in observed population. Lately, when analyzing implicit role of an individual in ensuring food safety, a psychological approach became important. The main goal of methodological analysis is to propose advances in research models that would tackle both qualitative and quantitative issues at the same time and offer new insights into barriers in HACCP system implementation. After analyzing the barriers to efficiency of the system, we identified elements that enabled us to cluster barriers into groups and identify the influence of specific elements on HACCP system efficiency. This paper is offering a novel approach to terminological classification of identified barriers, which will open new dimensions in assuring common language among food safety professionals in the future.

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lesions of gastric cancer. Genet. Mol. Res., 2014, 13 (4), 8695–8703. Zhang, Z. Y., Dai, Z. L., Yin, X. W., et al.: Meta-analysis shows that circulating tumor cells including circulating microRNAs are useful to

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hemodynamics and effects of phosphodiesterase type 5 inhibition in heart failure: A meta-analysis of randomized trials Hwang IC, Kim YJ, Park JB, Yoon YE, Lee SP, Kim HK, Cho GY, Sohn DW BMC Cardiovasc Disord 2017 Jun 12, 17, 150. doi:10.1186/s12872

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A rheumatoid arthritis kezelésében jelentős változást hoztak a biológiai készítmények. Számos randomizált, kontrollált vizsgálatban értékelték hatásosságukat. Ezekben a vizsgálatokban a beválogatott betegek jellemzői különbözőek, és az adagolás módja is eltérő lehet. A vizsgálatokban placebokontrollt alkalmaztak, hiányzik a biológiai kezeléseket közvetlenül összehasonlító eredmény. Célkitűzés: A rheumatoid arthritisben alkalmazott biológiai készítmények hatásosságának indirekt összehasonlítása a randomizált klinikai vizsgálatok eredményei alapján. Annak számszerűsítése, hogy a rheumatoid arthritis súlyosságával szoros összefüggést mutató betegségfennállás és a funkcionális állapot változói hogyan befolyásolják a terápiás hatást. Módszer: A szerző elvégzi az adatok metaanalízisét és metaregresszió alkalmazásával megvizsgálja, hogy a betegséget leíró változók hogyan befolyásolják a megfigyelt hatást. Eredmények: A rendelkezésre álló irodalom kiterjedt, a metaanalízis eredményei 32 vizsgálatban követett 18 500 beteg adatain alapulnak. Az egyes gyógyszerek placebóhoz hasonlított esélyaránya monoterápiában 3,6–20,0 között, míg kombinációban 6,4–35,5 között változott. A biológiai kezelések páronkénti indirekt összehasonlítása szerint a relatív esélyarány 0,3–5,5 között volt. A betegség fennállásának hossza és a hozzáadott hagyományos bázisterápia pozitív, míg a betegség súlyossága negatív kapcsolatban volt a biológiai szerek relatív hatásosságával. Következtetések: Az elemzés szerint a biotechnológiai gyógyszerek hatásossága hasonló. Súlyosabb betegeknél a relatív hatás kisebb, hosszabb betegségfennállás nagyobb relatív hatással jár együtt. Orv. Hetil., 2011, 152, 919–928.

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Scientometrics
Authors: Santosh Nanda, Ariel Rivas, William Trochim, and J. Deshler

Abstract  

The emphasis of validity as a publication content was investigated in dissertations and journal articles. The time of first publication, longitudinal publication profile, ratio of articles to dissertations, and time lag between dissertations and articles emphasizing validity were compared within and among various fields. A three-decade gap separated the first field adopting validity-related contents in its dissertations from the latest fields that did so. The longitudinal data suggested three groups of fields (Agricultural Sciences, Applied Sciences and Social Sciences) which showed consistent differences among groups and consistent similarities within groups in their emphasis on validity-related content. Adoption of validity-related content in dissertations always preceded adoption of validity-related content in journal articles. On average, less than 4% of journal articles included validity-related content across fields. These findings support the hypothesis that validity has been introduced and disseminated within fields following patterns predicted by diffusion of innovations theory. It is argued that this pattern is inconsistent with an efficient and interdisciplinary utilization of available knowledge. Policy recommendations are made for developing strategic communication and education programs for academicians and journal reviewers.

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Journal of Behavioral Addictions
Authors: Bernadette Kun, Zsofia K. Takacs, Mara J. Richman, Mark D. Griffiths, and Zsolt Demetrovics

, in these meta-analyses, the authors did not take into account the conceptual differences between workaholism and work addiction. Patel, Bowler, Bowler and Methe (2012) conducted a meta-analysis, but they only examined studies using the Work

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Laheij, R. J. F., Van Rossum, L. G., Jansen, J. B. M., Stratman, H., Verbeek, A. L.: Evaluation of treatment regimens to cure Helicobacter pylori infection: a meta-analysis. Aliment. Pharmacol. Ther., 1999, 13 , 857

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Journal of Behavioral Addictions
Authors: Martina Goslar, Max Leibetseder, Hannah M. Muench, Stefan G. Hofmann, and Anton-Rupert Laireiter

) format. Three of these meta-analyses ( Gooding & Tarrier, 2009 ; Leibetseder et al., 2011 ; Pallesen et al., 2005 ) included SGTs, but the number of trials was small, and further research has since been conducted. The latest meta-analysis in gambling

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