The kinetics of overall crystallization can be analyzed using the Avrami equation. Usually also called the JMAK equation (Jhonson-Mehl-Avrami-Kolmogorov equation).
This equation can be used for the overall cristallized fraction as a function of time (in isothermal experiments) or as a function of time or Temperature (non iso thermal exp.)
Look at Fig 3 in the attachement for an example of how to use this model.