Table 7.

The calculated dosimetric indices for the target volumes; dose non-homogeneity ratio (DNR), conformal index (COIN), and mean dose to the coldest volume (LCVaR). The clinics are denoted from A to E. Clinic B changed methods during the audit and provided two answers: B1, the old method and B2, the new method

	DNR			COIN			LCVaR
	PTV2mm	PTV3mm	CTV	PTV2mm	PTV3mm	CTV	CTV α = 5%	CTV α = 1%
A	0.21	0.21	0.18	0.74	0.80	0.55	10.34	10.07
B1	0.27	0.27	0.25	0.75	0.78	0.59	9.40	8.65
B2	0.30	0.29	0.28	0.76	0.82	0.57	10.17	9.35
C	0.33	0.31	0.32	0.70	0.78	0.52	10.21	9.41
D	0.25	0.24	0.23	0.75	0.83	0.56	9.35	8.33
E	0.24	0.23	0.22	0.74	0.80	0.55	10.50	10.22

PTV – planning target volume, CTV – clinical target volume