I used to ride competitively. They usually tested the top 5 finisher and an additional 5 chosen at random from the entire field of finishers. (the minimum number to get the volume discount from the testing lab.) For the pee test, you had to remove your shirt, and pull your shorts down to your knees then pee in a cup in front of total strangers/witnesses. Unless it was an important event, the results usually took a week to get back.