<P> The games of the tournament follow the rules of the International Ice Hockey Federation (IIHF), which differ slightly from the rules used in the NHL . The tournament follows the World Anti-Doping Agency's (WADA) rules on performance - enhancing drugs and the IIHF maintains a Registered Testing Pool (RTP), a list of top players who are subjected to random in - competition and out - of - competition drug tests . Several players have tested positive for banned substances since the 1972 Winter Olympics . </P> <P> In the men's tournament, Canada was the most successful team of the first three decades, winning six of seven gold medals . Czechoslovakia, Sweden and the United States were also competitive during this period and won multiple medals . Between 1920 and 1968, the Olympic hockey tournament was also counted as the Ice Hockey World Championship for that year . The Soviet Union first participated in 1956 and overtook Canada as the dominant international team, winning seven of the nine tournaments in which they participated . The United States won gold medals in 1960 and in 1980, which included their "Miracle on Ice" upset of the Soviet Union . Canada went 50 years without a gold medal, before winning one in 2002, and following it with back - to - back wins in 2010 and 2014 . Other nations to win gold include Great Britain in 1936, the Unified Team in 1992, Sweden in 1994 and 2006 and the Czech Republic in 1998 . Other medal - winning nations include Switzerland, Germany, Finland and Russia . </P> <P> In July 1992, the IOC voted to approve women's hockey as an Olympic event; it was first held at the 1998 Winter Olympics in Nagano . The Nagano Organizing Committee was hesitant to include the event because of the additional costs of staging the tournament, but an agreement was reached that limited the field to six teams, and ensured that no additional facilities would be built . The Canadian and American teams have dominated the event, typically losing only to each other . The United States won the first tournament in 1998 and the most recent in 2018 . Canada has won all of the other tournaments (2002--2014). </P> <P> The first Olympic ice hockey tournament took place at the 1920 Summer Olympics in Antwerp, Belgium . At the time, organized international ice hockey was still relatively new . The International Ice Hockey Federation (IIHF), the sport's governing body, was created on May 15, 1908, under the name Ligue Internationale de Hockey sur Glace . At the 1914 Olympic Congress in Paris, ice hockey was added to the list of optional sports that Olympics organizers could include . The decision to include ice hockey for the 1920 Summer Olympics was made in January, three months before the start of the Games . Several occurrences led to the sport's inclusion in the programme . Five European nations had committed to participating in the tournament and the managers of Antwerp's Palais de Glace stadium refused to allow the building to be used for figure skating unless ice hockey was included . The IIHF considers the 1920 tournament to be the first Ice Hockey World Championship . From then on, the two events occurred concurrently, and every Olympic tournament until 1968 is counted as the World Championship . The Olympic Games were originally intended for amateur athletes, so the players of the National Hockey League (NHL) and other professional leagues were not allowed to play . </P>

When was women's hockey introduced into the olympics
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