Table 2 Intra-reader agreement for the domains and scales used in the reliability exercise

Reader	Reliability	Synovitis (0–1 scale)	Synovitis (0–3 scale)	Doppler (0–1 scale)	Doppler (0–3 scale)	Osteophytes (0–1 scale)	Osteophytes (0–3 scale)
1	PEA	80.0	80.0	80.0	73.3	73.3	66.7
	PCA	–	100.0	–	73.3	–	93.3
	% m2>m1	66.6	66.7	0.0	0.0	100.0	100.0
	κ	0.602	0.679	0.471	0.348	0.375	0.561
	κ (w)	–	0.923	–	0.305	–	0.813
2	PEA	80.0	60.0	86.7	80.0	93.3	80.0
	PCA	–	86.7	–	100.0	–	100.0
	% m2>m1	0.0	16.7	0.0	0.0	100.0	66.7
	κ	0.471	0.474	0.667	0.536	0.842	0.719
	κ (w)	–	0.673	–	0.830	–	0.935
3	PEA	73.3	40.0	80.0	26.7	53.5	40.0
	PCA	–	93.3	–	80.0	–	80.0
	% m2>m1	50.0	77.8	66.7	63.6	71.4	77.8
	κ	0.444	0.172	0.571	0.088	0.087	0.172
	κ (w)	–	0.637	–	0.439	–	0.453
4	PEA	66.7	53.3	60.0	53.3	93.3	80.0
	PCA	–	100.0	–	100.0	–	93.3
	% m2>m1	60.0	57.1	33.3	28.6	0.0	100.0
	κ	0.074	0.356	0.211	0.132	–	0.664
	κ (w)	–	0.753	–	0.276	–	0.763
5	PEA	60.0	53.3	86.7	73.3	93.3	73.3
	PCA	–	86.7	–	93.3	–	100.0
	% m2>m1	16.7	28.6	0.0	25.0	0.0	50.0
	κ	0.224	0.255	0.595	0.250	0.762	0.620
	κ (w)	–	0.545	–	0.637	–	0.900
6	PEA	100.0	100.0	100.0	100.0	100.0	93.3
	PCA	–	100.0	–	100.0	–	100.0
	% m2>m1	–	–	–	–	–	100.0
	κ	1.000	1.000	1.000	1.000	1.000	0.911
	κ (w)	–	1.000	–	1.000	–	0.973
7	PEA	73.3	53.3	73.3	66.7	100.0	53.3
	PCA	–	86.7	–	93.3	–	100.0
	% m2>m1	100.0	85.7	100.0	100.0	–	85.7
	κ	0.444	0.327	0.250	0.085	1.000	0.327
	κ (w)	–	0.369	–	0.277	–	0.656

PEA, percentage exact agreement; PCA, percentage close agreement; κ(w), weighted κ; %m2>m1, percentage second scores higher than first score.