Figure 2.

Bland–Altman correlation between urea clearance obtained by two methods: urea clearance calculated with the described software (K_CALC) and urea clearance obtained by direct measure on prefilter blood and effluent samples (K_DEL). It is possible to distinguish the correlations between K_CALC and K_DEL, at therapy start (T₀) and after 18 to 24 hours of uninterrupted therapy (T₁₈).