Normally I don't post a lot on this subject, but if you need to keep track of messages, these are a couple services worth looking at. YouMail is for cell phones only and Got Voice can do both land line and cell phones. I use both!
The both have a free or light version. So why do I like services like this? Well a few months ago, Verizon had some voice mail issues, lost a bunch of them for folks all over for a couple days. I thought I was out of luck, but not so, I checked both of these services and guess what, voice mails! I used the web interface from my computer and they were all there, so it's a nice back up system.
Physicians could not afford to lose messages I would presume, so give this some thought, and even when you delete them from your phone, they are still here as a back up version from your computer, not bad. I have needed that reference too a couple times when I have been too quick on the draw. BD