Shat kriya kala, an approach towards disease manifestation

Diseases are of four types. Some diseases are easily curable, curable with difficulty, some can be managed and some of them are incurable. But there is an approach towards understanding the progress of disease manifestation. It is called as Shatkriya kala. Whereas Shat means six, kriya is action and kala indicates time. So, Shat kriya kala means six different stages of a disease. This understanding is very useful clinically.