Graphical displays for effective reporting of evidence quality tables in research syntheses

Background
When generating guidelines, quality of the evidence is tabulated to capture its several domains, often using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. We developed a graphic display to capture deficiencies, outliers and similarities across comparisons contained in GRADE tables.

Methods
Based on a systematic literature review capturing the effects of 32 different therapeutic comparisons on dysmenorrhoea, we synthesised evidence quality in tables and graphs. We evaluated time taken to accurately assess evident quality and preference for tables vs graphs.

Results
The plots provided visually striking displays of strengths and weaknesses of the evidence across the spectrum of comparisons on a single page. Equivalent tabulated information spread over 4 pages. Participants preferred and interpreted graphs quicker and more accurately than tables.

Conclusions
The graphic approach we developed makes interpreting evidence easier. Large tables are dry and cumbersome to read and assimilate. When guideline statements are accompanied by these plots, they have the scope for improving the credibility of the recommendations made, as the strength of the evidence used can be clearly seen. Further empirical research will establish the place for graphic displays.