Early in my career I had reverse engineered the DBF desktop database format (XBASE), and used that info to write programs in both Pascal and C (at different times) to read and print the metadata and data of DBF files. Later did the same in Python as part of xtopdf, my Python toolkit for PDF creation from other data formats. It was an interesting project for a relative beginner. Good fun.

https://en.wikipedia.org/wiki/XBase

xtopdf overview:

http://slides.com/vasudevram/xtopdf

DBFReader.py code:

https://bitbucket.org/vasudevram/xtopdf/src/default/DBFReade...

It's interesting that you didn't look at the binary that created this file and tried to reverse engineer it that way. If you're still looking for more, I'd suggest going through Instruments.app/Contents/Frameworks/InstrumentsAnalysisCore.framework/InstrumentsAnalysisCore.

binwalk is a good tool to use for this, especially early analysis: https://github.com/ReFirmLabs/binwalk

Putting "Instruments" in quotes would help. It's some program for Apple computers here. This is not about figuring out what measuring instruments are sending on the wire, something that's often proprietary.