STOCKHOLM (AP) - The director general of the World Anti-Doping Agency says the spread of nations that won medals at the London Olympics shows that efforts to fight doping have been successful.

At a conference Friday in Stockholm, David Howman said anti-doping campaigns have allowed "clean" nations like his native New Zealand to win medals "because it actually gets rid of the cheats who might have otherwise precluded countries like New Zealand from getting them."

New Zealand won 13 medals, tying its best total from 1988.

Howman said that if "you look at the other podium finishes from London, you will find a far greater spread of countries than you would have in 1984, 1980, 1976, and I think that's a really strong indication that anti-doping has had an impact."

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