Up to 57% of athletes admitted doping in the previous 12 months, a figure far surpassing the 1-2% identified by blood and urine tests carried out by the World Anti-Doping Agency (Wada), finds anonymous surveys carried out at two elite athletics competitions in 2011 published in Sports Medicine.

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Up to 57% of athletes admitted doping in the previous 12 months, a figure far surpassing the 1-2% identified by blood and urine tests carried out by the World Anti-Doping Agency (Wada), finds anonymous surveys carried out at two elite athletics competitions in 2011 published in Sports Medicine.