Cumulative meta–analysis: a new tool for detection of temporal trends and publication bias in ecology
Open Access
- 22 September 2004
- journal article
- Published by The Royal Society in Proceedings Of The Royal Society B-Biological Sciences
- Vol. 271 (1551), 1961-1966
- https://doi.org/10.1098/rspb.2004.2828
Abstract
Temporal changes in the magnitude of research findings have recently been recognized as a general phenomenon in ecology, and have been attributed to the delayed publication of non–significant results and disconfirming evidence. Here we introduce a method of cumulative meta–analysis which allows detection of both temporal trends and publication bias in the ecological literature. To illustrate the application of the method, we used two datasets from recently conducted meta–analyses of studies testing two plant defence theories. Our results revealed three phases in the evolution of the treatment effects. Early studies strongly supported the hypothesis tested, but the magnitude of the effect decreased considerably in later studies. In the latest studies, a trend towards an increase in effect size was observed. In one of the datasets, a cumulative meta–analysis revealed publication bias against studies reporting disconfirming evidence; such studies were published in journals with a lower impact factor compared to studies with results supporting the hypothesis tested. Correlation analysis revealed neither temporal trends nor evidence of publication bias in the datasets analysed. We thus suggest that cumulative meta–analysis should be used as a visual aid to detect temporal trends and publication bias in research findings in ecology in addition to the correlative approach.Keywords
This publication has 26 references indexed in Scilit:
- Damage‐induced changes in woody plants and their effects on insect herbivore performance: a meta‐analysisOikos, 2004
- Theory of plant defensive level: example of process and pitfalls in development of ecological theoryOikos, 2003
- Relationships fade with time: a meta-analysis of temporal trends in publication in ecology and evolutionProceedings Of The Royal Society B-Biological Sciences, 2002
- Fluctuating paradigmProceedings Of The Royal Society B-Biological Sciences, 1999
- Cumulative meta-analysis of clinical trials builds evidence for exemplary medical careJournal of Clinical Epidemiology, 1995
- Terpenes and phenolics in response to nitrogen fertilization: A test of the carbon/nutrient balance hypothesisChemoecology, 1993
- The Dilemma of Plants: To Grow or DefendThe Quarterly Review of Biology, 1992
- Problems induced by meta‐analysesStatistics in Medicine, 1991
- Acquisition and Allocation of Resources: Their Influence on Variation in Life History TacticsThe American Naturalist, 1986
- Carbon/Nutrient Balance of Boreal Plants in Relation to Vertebrate HerbivoryOikos, 1983