Table 3

Reproducibility of US endpoints.

10 MCP US endpoint

Reproducibility method

Baseline ICC (95% CI)

Day 15 ICC (95% CI)


Long PDA

Within-scan inter-reader

0.89 (0.80; 0.99)

0.98 (0.95; 1.00)

Parallel scan intra-reader

0.80 (0.64; 0.96)

0.62 (0.36; 0.88)

Parallel scan inter-reader

0.78 (0.59; 0.97)

0.68 (0.45; 0.92)

Long STA

Within-scan inter-reader

0.76(0.56; 0.95)

0.81 (0.65; 0.97)

Parallel scan intra-reader

0.95 (0.90; 1.00)

0.83 0.68; 0.98)

Parallel scan inter-reader

0.85 (0.72; 0.98)

0.71 (0.48; 0.95)

Long STi

Within-scan inter-reader

0.67 (0.40; 0.93)

0.54 (0.20; 0.88)

Parallel scan intra-reader

0.87 (0.75; 0.99)

0.82 (0.66; 0.98)

Parallel scan inter-reader

0.67 (0.42; 0.93)

0.46 (0.07; 0.85)

Long VASCi

Within-scan inter-reader

0.90 (0.81; 0.99)

0.94 (0.88; 1.00)

Parallel scan intra-reader

0.93 (0.87; 0.99)

0.94 (0.88; 1.00)

Parallel scan inter-reader

0.83 (0.67; 0.98)

0.85 (0.72; 0.99)

Trans PDA

Within-scan inter-reader

0.99 (0.98; 1.00)

1.00 (0.99; 1.00)

Parallel scan intra-reader

0.75 (0.57; 0.93)

0.76 (0.57; 0.94)

Parallel scan inter-reader

0.72 (0.51; 0.93)

0.75 (0.55; 0.96)

Trans STA

Within-scan inter-reader

0.52 (0.33; 0.72)

0.57 (0.36; 0.79)

Parallel scan intra-reader

0.83 (0.68; 0.98)

0.92 (0.85; 0.99)

Parallel scan inter-reader

0.57 (0.24; 0.89)

0.40 (0.01; 0.80)

Trans STi

Within-scan inter-reader

0.48 (0.19; 0.76)

0.36 (0.10; 0.62)

Parallel scan intra-reader

0.83 (0.68; 0.98)

0.77 (0.58; 0.97)

Parallel scan inter-reader

0.00 (-0.46; 0.46)

0.01 (-0.46; 0.48)

Trans VASCi

Within-scan inter-reader

0.92 (0.84; 0.99)

0.96 (0.92; 1.00)

Parallel scan intra-reader

0.73 (0.52; 0.94)

0.91 (0.84; 0.99)

Parallel scan inter-reader

0.68 (0.45; 0.92)

0.78 (0.60; 0.96)


ICC (intraclass correlation coefficient) values of <0.40, poor to fair agreement; 0.41 to 0.60, moderate agreement; 0.61 to 0.80, good agreement; and 0.81 to 1.00, excellent agreement. CI, confidence interval; PDA; Power Doppler Area; STA, synovial thickness area; STi, synovial thickness index; VASCi, vascularity index.

Seymour et al. Arthritis Research & Therapy 2012 14:R198   doi:10.1186/ar4034

Open Data