How is antithesis used to introduce the idea of an inefficient medical establishment within the military?

The first chapter is freewheeling and almost random, setting the satirical tone for the rest of the novel. Heller's cynicism about the war and the government is clear. An entire ward is pretending to be ill and is waiting for the war to end. Oddly, no one realizes what a widespread tactic this has become. Even worse, the men manage to avoid the front by the most ludicrous tactics, such as Dunbar's literal falling on his face.

The medical establishment is also severely ridiculed. Ironically, the men are seeking to avoid actual injury or death by pretending to be ill. Dunbar claims he can lengthen his lifespan by lying in a deathlike state for hours on end. Somehow the doctors are all deceived into believing that the entire ward is ill while the nurses have come to realize that the soldiers are simply pretending. Despite their extensive medical testing and knowledge, the doctors fail to realize that the men are faking their illnesses. They have been trained such that they can only recognize certain types of diseases, such as jaundice, and the fake illnesses that do not fit a known category bewilder them. Moreover, their methods of treatment are absurd. They keep on giving Yossarian a daily pill, hoping he will either get well or become jaundiced. The encased man is fed his own urine. All of this symbolizes the futility of life. At last, the stupidity of the doctors is exposed when the ill-educated, bigoted Texan proves that everyone in the ward except the C.I.D. man is a hypochondriac and sends them back to the front.