USNH Yokosuka does not have a sick call.  The hours above are times that you can schedule an appointment to see a doctor or Independent Duty Corpsman if you aren't feeling well and want to be checked out.  There are quite a number of times the doctors finish with patients early or people cancel, so calling ahead would be a good idea.  The weekend appointments are not for regular patients, they are seasonal and for PHA's only, in other words, anyone going IA or getting deployed (although OB GYN does do weekend pap smears, I believe, but I don't know the circumstances for those).  Also, the emergency room has no sick call hours either, and is for just that, emergencies.