Table 6.

Interobserver analysis for the AO Group classification.

Obs 1 x Obs 2	Observed agreement	Kappa coefficient	Kappa SE	p-value
MS x R3_1	62.0	0.499	0.074	< 0.0001
MS x R3_2	58.0	0.468	0.067	< 0.0001
MS x R2_1	62.0	0.501	0.074	< 0.0001
MS x R2_2	52.0	0.374	0.072	< 0.0001
MS x R1_1	54.0	0.388	0.075	< 0.0001
MS x R1_2	50.0	0.360	0.070	< 0.0001
R3_1 x R3_2	64.0	0.544	0.068	< 0.0001
R3_1 x R2_1	60.0	0.484	0.072	< 0.0001
R3_1 x R2_2	56.0	0.436	0.071	< 0.0001
R3_1 x R1_1	64.0	0.531	0.073	< 0.0001
R3_1 x R1_2	54.0	0.418	0.070	< 0.0001
R3_2 x R2_1	56.0	0.447	0.067	< 0.0001
R3_2 x R2_2	54.0	0.428	0.065	< 0.0001
R3_2 x R1_1	54.0	0.427	0.065	< 0.0001
R3_2 x R1_2	40.0	0.250	0.067	< 0.0001
R2_1 x R2_2	56.0	0.426	0.074	< 0.0001
R2_1 x R1_1	52.0	0.369	0.075	< 0.0001
R2_1 x R1_2	48.0	0.335	0.072	< 0.0001
R2_2 x R1_1	58.0	0.450	0.074	< 0.0001
R2_2 x R1_2	56.0	0.440	0.071	< 0.0001
R1_1 x R1_2	66.0	0.565	0.071	< 0.0001

Obs: observer; MS: medical specialists, R3: third-year resident, R2: second-year resident; R1: first-year resident, SE: standard error.

Source: SOT-HMMC, 2006.