We have to do these yearly. We do a self-appraisal and then we compare ours with what the project managers have for us. It can be a little awkward as sometimes they don't see or know everything you do. Most of the time we agreed though.
I'm glad I keep a daily work journal though. It sure came in handy and reminded them of stuff they forgot. Heck, I dealt with a couple of things this year that were delegated to me, but they didn't know and gave the other person credit for it (ie. the person who delegated). What really got me was that the person who delegated to me had their appraisal before mine and somehow forgot to mention it...
It is a little humbling though. There is a portion where you are supposed to list your doctorates and honourary degrees.