Table 4

Intrareader reliability* of MRI features in the distal interphalangeal (DIP) and proximal interphalangeal (PIP) joints (score range in brackets)

Single measure ICCPEAPCASDD
Synovitis (0–24)0.48 (0.09, 0.70)58 (45, 69)100 (99, 100)6.7 (5.0, 9.1)
Flexor tenosynovitis (0–24)0.51 (0.49, 0.65)58 (49, 67)95 (87, 100)4.9 (4.1, 5.3)
Erosions (0–48)0.92 (0.91, 0.96)81 (76, 81)99 (96, 99)5.8 (4.9, 7.9)
Cysts (0–16)0.21 (0.00, 0.57)98 (96, 99)NA1.3 (0.6, 2.5)
Osteophytes (0–48)0.88 (0.86, 0.89)65 (63, 69)99 (99, 99)6.1 (5.0, 9.5)
Joint space narrowing (0–24)0.97 (0.93, 0.99)81 (73, 88)100 (99, 100)2.3 (1.7, 2.5)
Malalignment frontal (0–8)0.79 (0.77, 1.00)96 (95, 98)NA1.0 (–, 1.2)
Malalignment sagittal (0–8)100 (99, 100)NA0.6 (–, –)
BMLs (0–48)0.89 (0.65, 0.89)89 (85, 89)99 (98, 100)3.7 (3.4, 3.7)
CL absence (0–16)0.81 (0.61, 0.81)86 (83, 86)NA4.9 (3.7, 5.4)
BMLs at CL insertion sites (0–32)0.81 (−0.07, 0.83)95 (94, 98)NA2.5 (2.0, 3.8)
  • * The values are median (minimum, maximum) for the three readers.

  • BMLs, bone marrow lesions; CL, collateral ligament; ICC, intraclass coefficient; NA, not applicable (dichotomous variable); PCA, percentage close agreement; PEA, percentage exact agreement; SDD, smallest detectable difference; –, scale or part of the scale has zero variance.