Some of the signs of pain in the babies are obvious, that it does not require of special equipment or training. The baby is crying and null and voidable when he is wide-awake, a pattern of altered dream is developed, it is fed bad, and it shows an afraid, distrustful reaction before the caretakers.

The classic Association the International for the Study of the Pain definition the pain like a subjective, emotional experience that is described in terms of damage to weaves, depends on the victim to be able pain car-report, that is very little used in the diagnosis and the treatment of the pain in the babies. More significant they are the nonverbal answers, of which there are two classes: the physical movements gross and measures of physiological answer. First they are the simple direct observation, whereas the second requires a specific equipment of control of the arterial pressure and the levels of hormonal stress.

The shout is the more and more important answer, since the investigators are now in conditions for distinguishing between different types from weeping: classified like “hunger”, “angered” and “fear or of pain”. The interpretation is difficult, nevertheless, depending on the sensitivity of the listener, and varies considerably between the observers.
The studies have looked for indicating additional, visible and easily definibles of pain. The combinations to cry with the face expressions, positions and movements, with the aid of physiological measurements, have been proven and it was verified that the trustworthy indicators. Several of those scales of observation have been published and verified