Mongodb + Mongoose.js - easy way to check that records conform to schema?

I have a mongodb DB which over time has been populated with data using various mongoose schema versions. I would like to run through these collections and verify that each document still conforms to the current mongoose schema.

What's the best way of going about this with Mongoose?

Document.validate can be a good start. After if you use mongoose in strict mode, it's really a bad idea to didn't transform documents when you change your schema