Usain Bolt did not use any illegal performance-enhancing drugs.
(96% probability)Question
Did Usain Bolt use performance-enhancing drugs?
01 Oct, 2020Answer
Background
Since around 2006, Jamaica has supplied many of the world's fastest sprinters. Some have used genetics to explain the Jamaican dominance in sprinting, some credit the Jamaican environment, while others believe that it is the result of rampant cheating in the form of Performance Enhancing Drugs (
Hypotheses Considered
Calculated Results
Calculated Results
1
95.9%
Usain Bolt did not use any illegal performance-enhancing drugs.
95.9%
2
3.5%
Usain Bolt started using illegal performance-enhancing drugs after age 15 in 2002, continuing to do so throughout his professional career.
3.5%
3
0.6%
Usain Bolt started using illegal performance-enhancing drugs before he was 15 in 2002, continuing to do so throughout his professional career.
0.6%
Starting Point
Initial Probabilities
Name
Initial Likelihoods
Clean
20%
PED as adult
74%
PED since teens
6%
Name
Initial Likelihoods
Clean
20%
PED as adult
74%
PED since teens
6%
Evidence
Effect
Fast since age 15
Name
Effect
Updated Likelihoods
Bolt has had outstanding performance at the global level since the age of 15. His increased speed falls within the normal range.
Missing evidence: signs of PED use.
Name
Effect
Updated Likelihoods
Drug tests
Name
Effect
Updated Likelihoods
Bolt has never failed a drug test and has been vocal against PED usage.
Name
Effect
Updated Likelihoods
Physical traits
Name
Effect
Updated Likelihoods
Bolt is very tall and his physical record lacks evidence of PED usage.
Name
Effect
Updated Likelihoods
Discussion