Trends in the Detection of Erythropoietin Receptor Agonists (ERAs) in Anti-Doping: An Analysis of Recent Adverse Analytical Findings (AAFs).

Anti-doping efforts aim to reduce the prevalence of doping through a combination of education, deterrence, and detection. Detection of doping practices, for example through testing and/or investigations, aims both to catch committed dopers and deter potential dopers. To date, little empirical evidence is available examining the ability of detection strategies to deter athletes from doping. Here, trends in adverse analytical findings (AAFs) for EPO or other EPO-Receptor Agonists (ERAs) were examined over an 8-year period in order to assess the impact of ERA testing and detection on athlete behavior. It was observed that the majority (62.8%) of ERA AAFs occur on samples collected on the day of a competition. Evidence is also presented that the largest fraction of ERA AAFs occurs on the first sample ever taken from an athlete (43.2%), and that the ERA AAF rates decline steadily as athletes continue to be tested. These findings provide evidence of a deterrent effect of testing on ERA use in sport.