Table 2.

Five sigmoidal fitted parameters.

Parameter	Mathematical meaning	Representation in amplification curves
$\mathbf{a}$	Amplitude of the function in the y-axis	Affect the maximum fluorescence that the amplification curves can reach
$\mathbf{b}$	Vertical shift of the function along the y-axis	Affect the maximum fluorescence together with parameter $a$
$\mathbf{c}$	Maximum slope of the sigmoid function	Related to the efficiency of PCR reactions
$\mathbf{d}$	Horizontal shift of the function x-axis	Fractional cycle of the inflection point (related to Ct values)
$\mathbf{e}$	Richard’s coefficient	Asymmetry of the sigmoidal trend