Susan, if you are using a psychiatric or partial psychiatric disability, it might be important to go back 10 years. For example, if you've had psychiatric visits fairly regularly for the past ten years, be sure to go back that far. If you had a short time back 10 years ago and then no more psychiatric visits/problems, then it might be hard to use it. However, if you've had even a few a year, I'd try to make it usable.
When you're doing this, TRY FOR ALL YOUR POSSIBLE PENSIONS ETC. There is no guarantee of anything, but if you only try for the easy part, that's all you'll get. I got disability, but even more importantly, that meant I had insurance on me and my husband for the rest of our lives. I want to say again: my eye dr who messed my eyes up with Lasik surgery told me that I'd never get social security. Well, he was wrong and so were a lot of others. You go girl, keep your head up and don't let people talk negatively to you. Lucy