how to check the impact of a field length change from 15 to 35 char in a standard table?

Hi Team,

There is one custom filed in VBAK table, i want to change the this custom filed length from 15 char to 35 char, but before this i need to prepare the impact of this field length change. so i have done the where used list and i prepared the impact, but in addition to this how can i check this impact from any interfaces and RFC objects?

Regards.