The normal interpretation of kinetic parameters in thermal analysis (DTA, TG) is deduced from isothermal experiments. In the present work, we propose a method which takes into account non-isothermal conditions, particularly high heating rates are considered. The new basic equation for the reaction rate includes in the Arrhenius relation the number of nuclei per unit volume in the sample at temperature T. This number is a function of the heating rate v. This model allows, in particular, to account for the curvature of the variation of ln(v/T_C²) as a function of the inverse of the crystallization peak temperature (1/ T_C) for high heating rates in DTA experiments. This model is applied successfully to DTA results on an amorphous CdGeAs₂ compound.