Traceability refers to the unit of measurement, not so much the actual method. For example, a caliper can be calibrated using a variety of methods (many specified by the manufacturer) but the calibration is traceable only when the standard used to calibrate the caliper can be traced to the NIST standard that is maintained for the dimension. As far as the frequency for calibration is concerned, this is your coice. Most often, you'll use the frequency suggested by the manufacturer. But if you use the item heavily, you may want to increase the frequency. If you don't see any change over a number of calibrations, you may want to reduce the frequency to save some time and money.
