In Oz lots of medical appointments are confirmed by text. Excellent idea. It's a reminder to the patient as well as allowing the doctor to use his time more effectively.
If I want to make sure they know of what I am Talking, or it's an ASAP...Phone, other wise how do I know they received the text? ...If I really don't want to talk with them and know that they text, then will text them. Sometimes will back up the text with an email to make sure they get the msg. ...If I cannot reach them on the phone and it is really important will do all three.