Hz to 15 MHz. This data should be collected for all magnetics that you build or specify during the design and development phase of your project. You will use the data to help evaluate new manufacturers, and as part of the comprehensive record of the magnetics' performance. Make sure that the short circuit you apply is of low impedance , especially for low-turn transformers. A terminating loop of just a few cm diameter can result in an inductance measurement significantly higher that the internal leakage of the transformer you are trying to measure.
Measure dc winding resistances with a four-terminal measurement setup.
You can use a simple lab current source and Fluke voltmeter to get very accurate dc measurements. A similar setup with the AP102B frequency response analyzer will produce good results at frequencies up to 1 MHz or more for low resistances. Leakage inductance is a function of frequency. Make sure you specify the measurement frequency for both leakage inductance and magnetizing inductance to your manufacturer. For most switch-mode power transformers, a sense resistor of either 0.1 or 1 ohm can be used to extract the needed frequency response data.