Various requirements for file formats have been put forward. One such list is as follows: A protocol should be: 1) simple, 2) self describing, 3) maintainable, 4) extensible, 5) N dimensional, and 6) have a universal data structure. The NetCDF format meets all of these requirements, suggesting that it is a good place to start. I would, however, add some more requirements to the list. Implied in the above list is the requirement that there be a standard for accessing data (how do I get the patient name) -- this is not provided by NetCDF. Furthermore, a useful format should come with a software interface that makes it easy to use, particularly in a development environment. Finally, a format that stores many associated pieces of information should also provide some data organization.
The MINC format attempts to add these things to the NetCDF format.