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Drugs in sport pie chart – use bar chart instead

With the Rio de Janeiro Olympics just around the corner, the excitement around the event has been ruined by doping scandals on a wide scale – even country-wide – never mind the Zika crisis.

We should be celebrating South Africa’s rowing team qualifying for Rio, or contemplating a Summer Games without Usain Bolt. But it’s the huge doping scandal that has all our attention.

While Rio 2016 will be a crucible for the IOC to try clean up athletes, step up the fight against drugs cheats, the rest of us sit on the sidelines with only a vestige of hope.

I saw this infographic on the multimedia section of the Eyewitness News website recently, which details the top ten doping nations and sports. The data comes from the World Anti-Doping Agency (WADA) 2014 Anti-Doping Rule Violations Report.

Pie chart showing the worst doping country offenders in 2014
Worst doping country offenders
Bar chart showing the worst doping sports offenders in 2014
Worst doping sport codes offenders

Pie chart

Had the nationalities data not been a pie chart but rather a bar graph (like the sports graph), the infographic would have been that much more powerful; allowing visitors to more easily compare nations.

Bar chart of the nationalities with the highest number of ADRVs were the Russia 148, Italy 123, India 96, Belgium 91, France 91, Turkey 73, Australia 49, China 49, Brazil 46, Republic of Korea 43
Bar chart version of nationalities with the highest number of ADRVs, Russia highlighted

Pie charts fail at trying to present useful data, which its creators don’t realise:

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But it is almost always difficult to compare the slices of a pie, because visual perception supports only rough comparisons of areas and angles, which are the two primary ways that pie charts encode quantities.
Stephen Few, Our Irresistible Fascination with All Things Circular (PDF)

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A bar graph is a better option as the data can be easily interpreted and compared. The display has no distractions, enabling the data to tell the story. Here I've highlighted the Russian Federation, which has the highest number of ADRVs (anti-doping rule violations).