Table 3.

Mean estimates, standard error, interindividual variability and descriptions of component parameters in the ecarin clotting time (ECT) concentration–response model based on data from the BISTRO I patient population

Parameter	Parameter estimate	RSE (%)*	IIV (%)†	RSE of IIV (%)*	Description
BAS0 (s)	28.0	0.49	8.2‡	8.98§	Baseline ECT at time 0 on the day of surgery
SLO0 (s ng−1 ml−1)	0.377	2.18	13.7‡	13.76§	Initial slope value (SLOP) at time 0, on the day of surgery
SLOF (s ng−1 ml−1)	0.268	1.49	NE	NE	Final slope value at time infinity
KM (h−1)	0.617	13.55	NE	NE	Constant describing the exponential rate of decline in the slope from 0 h to the final value
EMBA	0.175	6.46	NE	NE	Constant describing the maximum decrease in baseline ECT over time
ET50 (days)	2.86	13.50	NE	NE	Time point at which the baseline ECT has declined to half the EMBA
Residual error	6.63*	6.83	NE	NE	Proportional error reported as coefficient of variation (CV %)

^*RSE, Residual standard error. Percentage standard error for the parameter estimates was calculated according to percentage RSE: 100% · SE/parameter estimate.

^†IIV, Interindividual variability. Estimates of variance components (ω and σ) were converted into standard deviations by taking their square root. These are reported as coefficients of variation (CV %) after multiplying them by 100.

^‡Interindividual variability is based on values for E₀and SLOP rather than BAS₀(initial E_maxat time 0) or SLO₀(initial SLOP at time 0).

^§Percent SE is given on the variance scale; NE, not estimated.