Doctors who are trained in any speciality are only good in that particular area of speciality. That is why doctors in one department (speciality) refer any patient to another department (speciality), when they realise that the health problem is different from their own area of specislity. This is because the issue of de-skilling.

Doctors loss the skill & knowledge in any particular area if those skills and knowledge are not utilised or practiced for months or years. This is what is called de-skilling. In other words, the skill is lost due to inadequate usage or practice. This de-skilling process is more common as we have more of our doctors go it areas of specialization.

Doctors who are working in the provinces are usually better of and do not experience de-skilling as such, because they are doing every tasks of all other specialities. For example, the provincial doctors can deliver babies, they can put patients to sleep before operation (anaesthetic procedure), do operations, manage sick children (paediatic patients), etc. Therefore, these provincial doctors are better of and are unlikely to experience de-skilling. Infact, these provincial doctors are even better of because they even get more experience & skills so they have what we call, up-skilling.

So one can see that the Eye doctor has already been de-skilled in internal medicine. He should be allowed only to deal with Eye patients but not the general population with other illnesses.