There's some collage in here, yeah! Probably more than you're noticing, too. We do a lot of cut-and-pasting in zines.
Not going to lie, it was fun to try to replicate the visual style of diagnostic texts and academic articles. (Replicating the DSM was a huge formatting challenge!)
All of the quotes on the "how does the world sound in reverse?" page are altered from actual medical texts/guidelines and academic articles about DID, which was also a bit of an adventure. I remember that the ISSTD guidelines for DID treatment were one of the sources used there. I keep meaning to go back and track them all down so I can list proper credit.