GRADE and DODAR are essentially the same thing. BA uses DODAR, eJ use GRADE.
They are a decision-making framework designed to slow you down in a stressful situation and lead you to the correct course of action rather rushing into a potentially disasterous one - check out the Midland Kegworth incident..
G - Gather information - gauges, atc, cab crew etc
R - Reject irrelevant info
A - Analyse info and alternatives
D - Decide on a course of action
E - Evaluate and be prepared to change decision
You won't be expected to know everything about this at this stage but if you can show some multi-crew awareness, it'll come over well.