Table 1.

Inter- and intra-observer reliability (intra class correlation- ICC) of 99mTc-HDP-BTU activity using the localization and semiquantitative BTU grading scheme for the acetabular and femoral zones (Likert scale 0-10)

	Intra-observer-reliability				Inter-observer- reliability
Location	Observer 1		Observer 2		Observer 1-Observer 2
	Mean	95% CI	Mean	95% CI	Mean	95% CI
AS	0.954	0.913–0.976	0.975	0.952–0.987	0.900	0.815–0.947
AI	0.963	0.929–0.981	0.529	0.252–0.726	0.401	0.093–0,639
PS	0.967	0.938–0.983	0.949	0.903–0.973	0.950	0.905–0.974
PI	0.878	0.775–0.935	0.790	0.629–0.886	0.493	0.206–0.703
Z1	0.888	0.794–0.941	0.807	0.656–0.895	0.799	0.643–0.891
Z2	0.882	0.783–0.938	0.692	0.478–0.829	0.703	0.495–0.835
Z3	0.781	0.614–0.881	0.929	0.867–0.963	0.866	0.755–0.928
Z4	0.822	0.680–0.904	0.938	0.883–0.968	0.744	0.557–0.860
Z5	0.884	0.786–0.938	0.975	0.951–0.987	0.829	0.693–0.908
Z6	0.877	0.774–0.935	0.792	0.633–0.887	0.733	0.540–0,853
Z7	0.945	0.895–0.971	0.811	0.663–0.898	0.723	0.524–0.847
Z8	0.955	0.914–0.976	0.923	0.855–0.959	0.864	0.752–0.928
Z9	0.937	0.882–0.967	0.833	0.699–0.910	0.601	0.348–0.773
Z10	0.838	0.708–0.913	0.978	0.958–0.989	0.718	0.517–0.844
Z11	0.878	0.777–0.936	0.955	0.914–0.976	0.681	0.461–0.822
Z12	0.881	0.781–0.937	0.964	0.931–0.981	0.846	0.722–0.918
Z13	0.921	0.852–0.958	0.804	0.651–0.894	0.563	0.296–0.748
Z14	0.889	0.796–0.942	0.876	0.772–0.934	0.819	0.675–0.902
Acetabulum	0.975	0.953–0.987	0.967	0.937–0.983	0.877	0.774–0.935
Femur	0.992	0.984–0.996	0.981	0.963–0.990	0.871	0.764–0.932