Harvest Plots in evidence syntheses: A meta-research study on their use and characteristics to inform methods guidance

Evidence syntheses are a cornerstone of evidence-based healthcare. The methodological approach to synthesizing evidence is based on the underlying data material. When synthesizing evidence on complex interventions or overviews of reviews, traditional meta-analytical methods are of limited value and usefulness due to the clinical and/or methodological heterogeneity of the available evidence. The Harvest Plot was introduced in 2008 as a method to present the evidence from complex issues, e.g. complex or multicomponent interventions and their multiple effects and effect levels and study designs. Since then, the harvest plot has been used in different ways, with variations in terms of its descriptive features such as the height of the bars, the content of the rows and columns or the color scheme, as individual examples show. To contribute to the most informed and standardized use of the harvest plot, the aim of this study is to provide an overview of the use and characteristics of harvest plots in the context of evidence syntheses with health-related questions.

The results provide a systematic overview of the use and characteristics of the harvest plot in the context of evidence syntheses with health-related questions. It is expected that a heterogeneous picture will emerge. The diversity can be used to inform and prepare an expert study to develop a methodological and reporting guideline for the use of harvest plots in evidence syntheses.

Project outline on Open Science Framework