Table 2.

 Coefficient of variation values for the stereometric parameters generated in the test-retest study

Stereometric parameter	Coefficient of variation (%)
	HRT Classic				HRT Explorer				HRT-II Explorer
	I	II	III	IV	I	II	III	IV	I	II	III	IV
Cup area	26	21	16	27	25	25	25	24	25	25	23	19
Rim area	7	11	7	10	9	10	9	10	9	12	7	8
Cup volume	26	27	23	30	27	30	31	30	32	37	29	26
Rim volume	16	19	15	17	18	19	19	19	18	22	17	18
Reference height	11	14	11	13	11	15	13	16	17	17	13	13
Height variation contour	14	12	15	15	13	16	14	16	20	15	20	16
Maximum cup depth	8	7	10	8	8	7	10	11	12	13	10	12
Mean cup depth	8	8	9	7	7	8	9	11	11	11	9	10
Mean retinal nerve fibre layer thickness	21	21	32	19	20	23	18	22	31	27	25	22
Retinal nerve fibre layer cross sectional area	22	21	22	19	20	23	18	22	31	27	25	22
Cup shape measure	19	28	28	23	24	32	32	27	24	26	28	29

I = intraobserver/intravisit; II = interobserver/intravisit; III = intraobserver/intervisit; IV = interobserver/intervisit.

Low coefficient values equate to high repeatability.