Can public health researchers effectively communicate their findings? An evaluation of graph use at the 2006 European Conference on Public Health

Abstract

Aim To evaluate how researchers in the field of Public Health (PH) use graphical representations in the context of a scientific meeting. Subjects and methods We evaluated 159 graphs contained in the oral presentations given at the 2006 European Conference on Public Health. An ad-hoc data extraction form was developed on the basis of the available literature to evaluate type and characteristics of the graphs (e.g. format of axes, scales, legend, use of colours, presence of distortions). Principal component analysis (PCA) was performed to identify latent variables. Results We found that the majority of graphs were simple univariate displays such as bar diagrams (59.1%), and linear graphs (18.2%). Distortions were present in about 1 out of 3 graphs and they were less common in graphs made by researchers from northern and western European countries than in graphs made by researchers from other countries. Two factors emerged from PCA: clarity of the graph and appropriate use of colours. Conclusion The ability of PH researchers to fully exploit the visual potential of graphs appeared limited. Clarity and use of colours characterised use of graphics in oral presentations.

The relationship between sleep time and self-rated health: an analysis based on Italian survey data

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