How should medical mileage be recorded? Do I need beginning and ending mileage for the year like for a business if I'm not using the vehicle for a business?

For example, we went to the hospital many times this year.  Do we need to record the date of each trip with the distance or can I just add up all the trips we took and multiply it by the distance?  Also do I need to record it for each vehicle or for our family as a whole?