Described as the most scientific and comprehensive pre-event programme ever operated in the sport, it has been running since January 1 alongside World Rugby's annual testing and education regime.

The programme has been run in consultation with National and Regional Anti-Doping Organisations (NADOs and RADOs) operating in 22 countries and the International Olympic Committee (IOC)/World Anti-Doping Agency (WADA) pre-Olympic Games taskforce.

The programme is said to have captured all Olympic players from qualified nations as well as players from teams still in search of qualification during that period.

It comprised a total of 1,289 samples during the period with 83 per cent of tests conducted out of competition.

On average, it is claimed each player who has made it to Rio 2016 was tested 2.3 times in addition to testing programmes run by NADOs as part of their own pre-Games programmes.

In total, 70 per cent of controls were urine and 17 per cent of controls were for blood within a programme that included additional analysis of samples for erythropoiesis stimulating agents (ESA), such as erythropoietin, as well as for growth hormone releasing factors (GHRF) or human growth hormone (HGH).

The remaining 13 per cent were athlete biological passport (ABP) haematological module samples.

All urine samples were analysed as steroidal module ABP samples.

"Doping is one of the biggest threats to the integrity of sport and World Rugby continues to be committed to protecting clean athletes through intelligent testing and values-based education," said World Rugby chairman Bill Beaumont.

"World Rugby upholds the values of integrity, discipline and respect.

"Our top men's and women's sevens players are excited to be representing rugby on sport's biggest stage and look forward to showcasing rugby's character-building values to educate aspiring sports men and women that there are no short cuts to the top."

All samples have been stored to enable future analysis and to date, there have been two recorded adverse analytical findings during the period which were announced earlier this year.

Two Russian players, Alexey Mikhaltsov and Alena Bogacheva, tested positive for meldonium but were subsequently cleared to play following their respective hearings in line with WADA's notice regarding that substance.

Russia have not qualified for either the men or women's tournament at Rio 2016. 

Earlier this month, WADA extended the period during which athletes may escape punishment if they have tested positive for meldonium from March 1 to September 30. 

Under revised guidance, athletes who provided a urine sample which returned a positive test for the heart-attack drug between January 1 and February 29 can also be given a "no fault" verdict if their sample contained less than five micrograms of meldonium.

This marks an increase from the previous set of guidelines published by WADA, which stated if below one microgram of meldonium was detected and the failed test came before March 1, a negligence or no fault verdict could be reached.

"World Rugby is committed to effective, risk-based anti-doping testing, and we also take our role very seriously to ensure that players at all levels of the game understand that there is no place for doping in our sport," Mike Earl, World Rugby’s anti-doping general manager, said. 

"This dedicated pre-Olympic programme, featuring a more than 5:1 proportion of out-of-competition versus in-competition testing, haematological and steroidal biological passports, and additional analysis conducted on 65 per cent of all samples collected, reflects our commitment to effective test planning and analysis in this important area.

"It is the most scientific and comprehensive pre-event programme ever operated in our sport.

"Rugby is proud to work in partnership with our NADO and RADO colleagues and to support WADA and the IOC in contributing to what we hope will be a fantastic Olympic Games in Rio."

Launched in 2005, World Rugby’s "Keep Rugby Clean" programme aims to educate players within the game about anti-doping, including at lower levels and also in schools.

It has delivered education to more than 15,000 players at World Rugby events, including the men's and women's HSBC World Rugby Sevens Series and Olympic Games repechage events.

Problems still exist in rugby union in Britain, however, where 23 players are currently serving bans for failing drugs tests.

UKAD chief executive Nicole Sapstead has described it as a "worrying trend".

Fifteen-a-side rugby union has appeared at four versions of the Olympics - last doing so in Paris in 1924 - but Rio 2016 will mark the debut of the sevens variant of the sport.