Just call nuh or sgh and inform that you have a referral letter but your preference is actually nuh/sgh.. If you have appt before hvg referral letter also possible but they will charge you private for the 1st visit then only subsidize once referral ltr given..
If you want to pay a subsidised rate then you need to go through polyclinic to get a referral. If you make appointment on your own, you will be charged private rates.
SweetHoney Mimi