How long can the medical rectification check reveal blindness?

It usually takes a month to arrive, but it takes two months. It usually takes one or two months from the completion of the third phase clinical trial of drugs to the uncovering of blindness. After the registration is completed, data entry and data analysis are required, and then the data can be checked and modified. After several times of data analysis, the data can be summarized, and then the blindness can be uncovered.