THE United States is poised to claim a stunning overall victory at the Games, even though the host nation China has won nearly double the number of gold medals.

So who is No. 1? How can there be two winners, two tallies? The confusion arises because of the different ways of measuring Olympic success based on the number of overall medals or on a ranking system using gold medals.

"We always consider the overall number of medals because it shows the true strength of the team. The gold medals take care of themselves," the United States Olympic Committee's director of media services, Bob Condron, said. "We rank the countries according to total number of medals so if we say we won the medal tally, it means we won it overall."

Chinese Olympic Committee officials could not talk about the medal tally because it was a topic sensitive enough for only the most senior party officials. But in China, and in most parts of the world, the medal tally is calculated by the number of gold medals, with the other medals used to break a tie.

The International Olympic Committee ranks the medal standings on its official information service both ways. Historically the IOC has rejected the notion of any medal tally, but in recent years it has become a talking point, and a means to lobby governments for sports funding.

Last night China led the tally based on golds, with the US second and Australia third. But on the US measurement, the US was leading overall, followed by China and Australia. However, Australia is tipped to fall to around sixth overall.

If it appears obvious that the gold medal standard is the way to go - as published by Australian newspapers, websites and broadcasters - think again.

The Australian Olympic Committee has used a total medal tally forecast for the past couple of Olympics. For Beijing, Australian success was measured on finishing in the top five - based on the overall tally, not numbers of golds.

"Generally we look at the overall medals when it comes to our objectives, because it is so hard to predict the number of golds," said the AOC president, John Coates, who had tipped 42 to 48 medals.

So who should claim the global medal victory, China or the United States? Coates believes it should be the overall winner, not the number of golds.

But Coates said maybe the medal tally should be calculated on the number of each team's medallists. "In Athens we had 482 competitors and 158 medallists, so a third of the team came home with a medal - that is because we do so well in team sports," he said.