Medical Info on Cell Phones

I was updating my emergency info on my phone the other day, and realized it had a spot for medical conditions and info. It got me thinking. In an emergency when the patient is compromised or unconscious, do you actually look at their phone for this info? For John or Jane Does, do you specifically try and find their phone, if available, to see if they've entered it? Or is it a complete waste of my time to put it in?