Doping in tennis

David Howman expresses his thoughts about anti-doping policies in certain sports organizations. While the director general of the WADA seems to be happy with jobs of several sports organizations, he notes that anti-doping programs in other leagues/teams are not proper.
For example, David Howman praises the International Tennis Federation (ITF) for its anti-doping system. David Howman says that anti-doping system is appropriate in tennis.
But as for the National Basketball Association (NBA), it doesn’t agree to adopt its anti-doping system to that of the WADA. It refuses to add certain new drug tests in order to catch those who take steroids and/or other prohibited preparations. That’s why the director general of the WADA notes that the anti-doping system of the NBA is not good enough to catch those who dope. He confirms that the NBA should add more sophisticated new methods as well.
The director general of the WADA claims that drug tests conducted in tennis are of high quality. But there is a defect in tennis’ anti-doping program. A lot of tests are conducted during competitions. But few tests take place out-of-competition. That’s why ITF’s anti-doping system is also criticized.
Of course, no one can confirm that anti-doping program of ITF is perfect. It has some lacks too. But it is quite adequate.
Thus, you should not believe that tennis is clean from doping wholly. Certain tennis players are likely to administer steroids and/or related medicines. But it is not so tainted, as certain other sports.
 Only one tennis player was banned for intake of forbidden drugs. Although it seems to prove that tennis is clean, it is important to consider that there are certain methods to avoid positives. As you probably know, the American cyclist Lance Armstrong took steroids and other related products and avoided detection much time. Couldn’t tennis players act the same way?