Kirsten McCaffery|Ann Dixon|Andrew Hayen|Jesse Jansen|Sian K Smith|Judy M. Simpson
The Influence of Graphic Display Format on the Interpretations of Quantitative Risk Information among Adults with Lower Education and Literacy
University of Sydney|University of Sydney|University of Sydney|University of Sydney|University of Sydney|University of Sydney
test optimal graphic risk communication formats presenting small probabilities using graphics denominator 1000 adults lower education literacya randomized experimental study took place adult basic education classes sydney australia participants 120 adults lower education literacy experimental computerbased manipulation compared 1 pictographs 2 forms shaded blocks unshaded dots 2 bar charts across different orientations horizontalvertical numerator size small 100 medium 100499 large 500999 accuracy size error ease processing reaction time assessed gist task estimating larger chance survival verbatim task estimating size difference preferences different graph types also assessedaccuracy gist task high across conditions 95 tested verbatim task optimal graph type depended numerator size small numerators pictographs resulted fewer errors bar charts blocks odds ratio 0047 95 confidence interval ci 00230098 dots 0049 95 ci 00240099 medium large numerators bar charts accurate eg medium dots 429 95 ci 29635 pictographs generally processed faster small numerators eg blocks 149 seconds v bars 162 seconds bar charts medium large numerators eg large blocks 416 seconds v 267 seconds vertical formats processed slightly faster horizontal graphs difference accuracy participants preferred bar charts 64 however relationship performancefor adults low education literacy pictographs likely best format use displaying small numerators 1001000 bar charts larger numerators 1001000