VANCOUVER - The events have been run, the medals awarded. And now we wait.

The next couple of days could still see positive doping tests from the Vancouver Olympics as the anti-doping lab processes samples taken in the final events of the Games.

But even if no new positives pop up and it turns out the only doping infractions caught here were two cold medication-related wrist-slaps, that doesn't necessarily mean the Vancouver Olympics will go down in history as virtually clean Games.

The statute of limitations in the Olympic world is eight years. In that time, the International Olympic Committee can order reanalysis of samples taken during an Olympics if advances in testing methods open up new possibilities to detect cheating.

That means results recorded and medals doled out in Vancouver could be rewritten and reclaimed at any time during that eight-year window.

"You could ask me: When will you know exactly what the tally will be for Vancouver? Well, that's in eight years time — 2018," IOC President Jacques Rogge cautioned in his closing press conference of the Games.

The eight-year rule gives the IOC a way to neutralize the jump-start cheaters have on the system in place to try to catch them. Until the labs know of the existence of a new drug or doping method, it can pass under the radar.

"It's always the same problem. You don't know without positives whether you missed something that your testing wasn't that good for," said Dr. Don Catlin, a veteran of the anti-doping effort and the man who directed the IOC drug labs at the Los Angeles, Atlanta and Salt Lake City Olympics.

The retroactive testing rule puts athletes and their entourages on notice that doping with something that's undetectable now is no guarantee they won't be exposed and held to account later.

"One of the great things about this is we don't necessarily have to find it now. We keep these samples for eight years precisely for (this) reason," said Canadian IOC member Dick Pound, former chair of the World Anti-Doping Agency.

The retroactive testing rule has already paid off. Less than a year after the Beijing Summer Olympics in 2008, a test for a new blood boosting drug, Micera, became available. Retesting found six athletes who had taken CERA, as it is called. One, Rashid Ramzi of Bahrain, was stripped of a gold medal won in the 1,500 metres race.

A similar situation could happen after the Vancouver Olympics.

Dr. Arne Ljungqvist, head of the IOC medical commission, said late last week some blood tests were being reanalyzed because there was a suspicion the lab might have been seeing signs of doping.

It might be use of a new variant of the drug EPO (erthyropoeitin), which promotes generation of new red blood cells, he suggested. Anti-doping experts have been on the lookout for signs of use here of a new EPO-like drug, Hematide, which hasn't even hit the commercial market yet.

Blood doping is used by cheating athletes in endurance sports such as cross-country skiing, biathlon and some distances of long-track speedskating.

Ljungqvist classified the suspicion as "low grade" and gave no indication which athletes or which sports might have been under additional scrutiny. He also didn't give any sense of how soon answers might be forthcoming. So only time will tell whether athletes who competed at Vancouver will be caught for Hematide use.

"My sense would be that we would have seen Hematide by now if we were going to see it," said Catlin, who had earlier predicted that Hematide would make an appearance at these Games.

"But since we haven't seen it, it doesn't mean it's not there. It just means the (testing) method, it almost certainly means it's not ready yet."

Even though the possibility of positives still looms over the Vancouver Games results, many involved in the fight to keep doping out elite sport are expressing optimism that the likelihood of athletes cheating while at the Olympics may be waning.

"Well, I think that the athletes who come here — unless there's something that absolutely nobody knows about — are much aware that Christiane Ayotte runs an absolutely first class lab," said Pound, referring to the director of Canada's anti-doping lab.

"And if there's stuff in their system, they're going to get caught. So that's a fair deterrent."

Rogge said the IOC sees a trend in the fact that there were seven cases each at the Salt Lake City Games of 2002 and Turin in 2006, but only two in Vancouver. (Turin only produced one positive test, but six Austrian cross-country skiers were found with blood doping equipment and were later banned for life from Olympic competition.)

The two cases detected so far in Vancouver were both hockey players who used cold medications with banned stimulants. Both were given reprimands only — a move which puzzled Catlin.

The World Anti-Doping Agency re-added the stimulant pseudoephedrine to the prohibited list this year after several years of monitoring testing showed it was being widely used in competition.

But experts acknowledge that finding no significant doping cases during the three weeks or so of the official Olympic period doesn't mean athletes aren't using during the three years and 11 months between Games, when they actually stand to benefit most from some types of doping.

"I think overall we've done a much better job. But nobody will tell you that the job is finished.... We've covered more of the holes that needed to be covered — but not all of them," Catlin said.

"That's just the way it is. We can be sort of happy that we've got somewhere but we can't stand up and say 'We got drugs out of the Olympics.' Forget that. That's not the case."

"There's somebody out there that's getting away with it. Or there's somebody out there developing a new approach that will beat the tests.... But clearly we're (moving) in the right direction.