Side stitches while running can have various causes, just like most other symptoms. Finding the true cause means ruling out or confirming each possibility – in other words, diagnosis.
Diagnosis is usually a complex process due to the sheer number of possible causes and related symptoms. In order to diagnose side stitches while running, we could:
When you exercise (run, walk fast, cycle, etc.), do you get a 'side stitch'?
Possible responses:→ I don't exercise / don't know
→ No, never
→ Regularly, but under half the time
→ Most of the time