How to calculate Electrochemical Active Surface Area (ECSA) for Screen printed electrodes (SPE)?

In SPE electrodes, the geometrical surface area is determined by its physical dimension but it is impossible to determine whether the electrode surface is inert or electrochemically active. Two electrochemical techniques are used to determine the ECSA of SPE such as:
1. Cyclic voltammetry (using Randles–Sevcik equation).
2. Chronocoulometric (using Anson equation).