When setting up an HL7 interface, the most fundamental question that you need to ask yourself as a developer
is how much information do I require?
In most cases, you will need either:
Only a small subset of the information, or
Just about everything.
If you only need a small subset of the data then
you are very lucky - you'll be able to save yourself a lot of
work. On the other hand, if you know you need just about
everything then you can definitely minimize your work by
designing your segment grammar accordingly.
Your segment grammar design
must be driven by your data requirements.