I recommend you start with this document: In-Depth: Charting
Charting is challenging to 'get', but once you do, it is an amazing tool.
You want to show the scores for one patient over time? I recommend looking at the chart option "Related Records" or "Current Record" to get you started.
I use ExecuteSQL in my charts, as does many developers. Do you use the ExecuteSQL function at all? If I were on a patient's layout, I'd use ExecuteSQL to return all the scores from that patient over time, as well as those dates. There's another thread here asking the very same question.
Many thanks for the quick reply.
I will have a look at the suggested document. I can code up to HTML so I haven't really considered more advanced scripting in filemaker.
It sounds that I should do exactly what you suggest...get their scores over time, and then chart them!