Since Chepn'getich's suspension, I've fallen down a bit of a research rabbit hole on doping. In doing so I came across a very interesting study published in 2018 which surveyed athletes at two major international competitions - one of which was the 2011 IAAF World Championships.
The researchers randomly approached athletes and gave them an anonymous survey on a tablet, asking if they had knowingly violated anti-doping regulations by taking a prohibited substance within the last 12 months. They also tracked how long it took each respondent to take the survey.
The result: 43.6% of athletes responded that they had knowingly doped in the last 12 months.
Now, my initial reaction was one of skepticism in the methods of the survey. I'm still not sure I fully understand the study design (they used something called an Unrelated Question Model), but they go into some depth as to how they control for errors or unintended "yes" responses. Specifically, they looked at how the numbers change if they took out the top 10-50% of respondents in terms of how fast they took the survey - the thinking being that some athletes may have taken the survey so quickly they didn't actually stop to pay attention to what they were answering. "The prevalence estimates decreased upon deleting the 10%-20% of fastest respondents, but stabilized thereafter.
You can read the full text here:
So assuming this survey is statistically sound and that no clean athlete would knowingly respond "yes"... why in the world would these athletes answer honestly? What's the incentive? The study was anonymous and randomized, but you don't dodge doping control by being honest. I'm still trying to wrap my head around that part.
But 43.6% is a lot. Especially when you consider that a significant portion of doping respondents were probably smart enough to not answer "yes." It's hard to not look at this study and think that the whole sport is dirty top to bottom.