Table 1 Difference values (as a percentage) between various methods with sub-complete data when compared to the full data set analysis (gold standard method); method 1: t1/2 average applied to 4 h data; method 2: t1/2 average applied to 24 h data; method 3: t1/2 patient from cycle 1 applied to 4 h data on subsequent cycles; method 4: t1/2 patient from cycle 1 applied to 24 h data on subsequent cycles; method 5: cycle 1 %IA at 120 h applied to subsequent cycles with only 4 h and 24 h data acquired