Drug tests conducted in tennis

David Howman expresses his opinion about point of view about anti-doping policies in some sports organizations. While the director general of the WADA is happy with jobs of several sports organizations, he notes that anti-doping policies in other leagues/teams are not appropriate.
For example, David Howman praises the International Tennis Federation (ITF) for its anti-doping system. David Howman says that anti-doping program is suitable in tennis.
But as for the National Basketball Association (NBA), it doesn’t want to adopt its anti-doping program to that of the WADA. It doesn’t agree to add certain new drug tests in order to catch those that use steroids and/or other forbidden medications. That’s why the director general of the WADA affirms that the anti-doping system of the NBA is not good enough to detect those who dope. He claims that the NBA should add more sophisticated new methods as well.
David Howman claims that drug tests conducted in tennis are of high quality. But there is a defect in tennis’ anti-doping program. Numerous tests take place during competitions. But few tests take place out-of-competition. That’s why ITF’s anti-doping policy is also criticized.
Of course, no one can claim that anti-doping system of ITF is perfect. It has several lacks too. But it is quite adequate.
So, you should not think that tennis is clean from doping wholly. Several tennis players are likely to administer steroids and/or related preparations. But it is not so tainted, as some other sports.
 Just one tennis player was banned for application of banned substances. However it seems to prove that tennis is not tainted, it is important to consider that there are certain methods to prevent positives. As you probably know, the prominent cyclist Lance Armstrong administered steroids and other related preparations and avoided detection much time. Couldn’t tennis players act the same way?