Explain Your Return Call Policy: In your after hours message for the medical office, be sure to state your return call policy for voicemail response. By giving callers an estimate of when they can expect a return call from someone in your office, you can eliminate multiple phone calls from the caller, as well as reduce work for your staff members.
Voicemail and voice messages are among the top ways every professional business can use to enhance their customer services. Though this idea may sound strange to many in the internet age, this kind of mail is a proven source of solutions for business communications and customer service.

Save time with Call Return. Press 88 after listening to a message to automatically dial the number of the person who called. (This feature will not work if the caller has Caller ID Blocking.) Reply to or forward messages
You might also consider giving them the option to skip your voicemail message completely by pressing another key (again, check with IT). You also want to make callers aware what you will return their call, instead of telling them that you will try to return their call--and let them know when you are likely to do it, if possible. If necessary, provide additional or emergency information in your voicemail greetings. My dentist, for example, lists his cell phone number for emergencies.