The Kt/V value demonstrates the dose of hemodialysis (HD). However, because of several existing methods for calculating delivered dialysis dose, Kt/V values can, in fact, be different for the same set of pre-/post-dialysis blood urea concentrations. We prospectively compared the “gold standards” of prescribed (urea kinetic model, UKM), delivered (Daugirdas second-generation) Kt/V and values obtained via the other existing formulae with values obtained using the new system dynamics model for calculating dialysis adequacy and session performance to see whether reliance on the latter approach was likely to lead to errors in over- or underprescribing dialysis regimens. Data were processed on 134 dialysis patients. The statistical analysis reveals that system dynamics model Kt/V values were statistically different (p < 0.05) from the calculated Kt/V values from other models, except for those Kt/V values calculated according to the Basile (P = 0.064), Ijely (P = 0.475) and Daugirdas Second Generation (P= 0.54).