Since London 2012 though, high-profile sprinters including Asafa Powell have tested positive for banned substances.
But the IAAF, athletics’ governing body, insists it extensively tested elite Jamaicans throughout that period.
The country’s sprinters won eight individual medals at the London Games.
But in recent months, Jamaica’s reputation has been tarnished with news of positive tests by Powell, Sherone Simpson and three-time Olympic gold medal winner Veronica Campbell-Brown.
Former Jadco director Renee Anne Shirley alleged in August that athletes were not tested outside of competition for five of the seven months before last year’s Olympics.
While the organisation’s chairman Herbert Elliot has dismissed her claims, Wada director-general David Howman believes there is an issue.
“There was a period of, and forgive me if I don’t have the number of months right, but maybe five to six months during the beginning part of 2012 where there was no effective operation,” Howman told the Associated Press.
“There might have been one or two, but there was no testing. So we were worried about it, obviously.”
Jadco is not the only body which would carry out drug tests on Jamaican athletes.
An IAAF spokesman told the Associated Press its own out-of-competition programme was “robust and comprehensive”, with tests carried out at Jamaican training camps.
Meanwhile, all athletes finishing in the top five places at the London Games were tested by the International Olympic Committee.
Howman said Wada would focus on the lack of out-of-competition testing carried out by Jadco itself as a “high priority”, although these inquiries are not expected to be completed by the end of the year.