Table 6 Inter-observer agreements for MRI changes in the SIJ and global assessment

BMO

AB

97.77

89.52

.79 (.69–.86)

384

AC

98.09

91.08

.79 (.68–.87)

384

BC

98.70

91.38

.85 (.79–.90)

384

Combined¹

.81 (.78–.84)

384

  Intensity BMO ²

AB

85.00

72.22

.46 (.19–.73)

60

AC

-

-

-

-

BC

-

-

-

-

Combined¹

-

-

  Depth BMO ²

AB

85.00

53.67

.68 (.49–.87)

60

AC

82.35

50.52

.64 (.43–.85)

51

BC

92.86

53.06

.85 (.71–.99)

56

Combined¹

.73 (.63–.82)

65

FMD

AB

97.25

83.26

.84 (.77–.89)

384

AC

97.19

87.28

.78 (.69–.85)

384

BC

95.60

84.77

.71 (.60–.80)

384

Combined¹

.78 (.74–.81)

384

  Depth FMD ²

AB

84.91

56.14

.66 (.44–.87)

53

AC

78.05

63.65

.40 (.08–.71)

41

BC

72.55

58.94

.33 (.07–.60)

51

Combined¹

.52 (.38–.67)

67

Erosions

AB

97.77

92.99

.68 (.49–.81)

384

AC

98.32

96.12

.57 (.30–.76)

384

BC

96.90

94.69

.42 (.20–.63)

384

Combined¹

.57 (.51–.62)

384

Subchondral sclerosis

AB

98.73

96.29

.66 (.40–.81)

384

AC

99.16

97.21

.70 (.37–.87)

384

BC

98.87

97.15

.60 (.28–.81)

384

Combined¹

.65 (.61–.70)

384

Ankylosis

AB

-

-

-

-

AC

-

-

-

-

BC

99.28

97.26

.74 (35–.90)

384

Combined¹

-

-

Global assessment³

AB

94.2

81.31

.69 (.44–.86)

47⁴

AC

90.75

74.95

.59 (.35–.75)

44⁴

BC

89.39

74.64

.58 (.32–.78)

43⁴

Combined¹

.61 (.46–.75)

47⁴