Supplementary Table 1 (For Online Publication): Monthly Quality Assurance Process, And

Supplementary Table 1: Monthly quality assurance process, and test-retest reliability studies of Osteoarthritis Initiative (OAI) pilot imaging data (cartilage segmentation)

Authors Imaging Method Analysis Type n = Knees / Key Results Participants Schneider et al.S7 Various Test-retest phantoms Good stability of geometrics measures over time OAI sequences High consistency of geometrics measures across the sites RMS CoV% = 0.04% for diameter measures RMS CoV% = 0.56% for length measures RMS CoV% = 0.46% for spherical volume measures RMS CoV% =2.3 to 18.8% for T2 relaxation times Eckstein et al.S4 cor FLASH Non-paired test/ 19/19 Femorotibial joint: cor MPR DESS retest analysis; RMS CoV% = 3.0-6.4% with coronal FLASH sag DESS cartilage volume RMS CoV% = 2.4-6.2% with coronal MPR DESS RMS CoV% = 2.3-8.2% with sagittal DESS Correlation of DESS vs FLASH r = 0.88 to 1.0 Femoropatellar joint: RMS CoV% = 3.4-8.5% with sagittal DESS

Eckstein et al.S5 cor FLASH Paired test /retest 19/19 RMS CoV% ≤ 2.6/2.3% (FLASH/MPR DESS) quadrature coil cor MPR DESS analysis cartilage RMS CoV% ≤ 2.3/2.5 % (FLASH/MPR DESS) phase array coil volume / thickness; statistically significant differences between coils coil comparison greater precision for compartment vs. plate measures

Brem et al.S1 sag DESS Paired test /retest 12/12 RMS CoV% ≤ 1.2% for cartilage volume analysis cartilage RMS CoV% ≤ 1.5% for cartilage thickness volume / thickness Eckstein et al.S6 cor FLASH Paired test/retest 9/9 RMS CoV% = 1.8%; 2y loss = -1.7% (cor FLASH) cor MPR DESS analysis and two-year RMS CoV% = 3.0%; 2y loss = -0.3% (cor MPR DESS) sag DESS sensitivity to change RMS CoV% = 2.6%; 2y loss = -2.8% (sag DESS)

Tamez et al.S8 sag DESS Paired test/retest RMS CoV% = 0.6%-1.6% for cartilage thickness and two-year change RMS CoV% = 3.6%-11.7% for bone curvature analysis ICC for reproducibility of change 0.00-0.87 cor = coronal; FLASH = fast low angle shotsequence (= SPGR = spoiled gradient recalled); MPR = multiplanar reconstruction; sag = sagittal; DESS = double echo steady state sequence with water excitation; RMS CoV% = root mean square coefficient of variation; Please note that the OAI pilot studies built on previous work comparing cartilage volume and thickness measurements obtained from 3 Tesla MRI with that obtained from 1.5 Tesla MRI S2, with 1.5 Tesla MRI having been previously validated versus external reference methodology S3

Supplementary Reference List

S1. M. H. Brem, et al., "Magnetic resonance image segmentation using semi-automated software for quantification of knee articular cartilage---initial evaluation of a technique for paired scans," Skeletal Radiol. 38(5), 505 (2009).

S2. F. Eckstein, et al., "Accuracy and precision of quantitative assessment of cartilage morphology by magnetic resonance imaging at 3.0T," Arthritis Rheum. 52(10), 3132 (2005).

S3. F. Eckstein, et al., "Magnetic resonance imaging (MRI) of articular cartilage in knee osteoarthritis (OA): morphological assessment," Osteoarthritis Cartilage. 14 Suppl 1: 46 (2006).

S4. F. Eckstein, et al., "Double echo steady state magnetic resonance imaging of knee articular cartilage at 3 Tesla: a pilot study for the Osteoarthritis Initiative," Ann. Rheum Dis. 65(4), 433 (2006).

S5. F. Eckstein, et al., "Impact of coil design on the contrast-to-noise ratio, precision, and consistency of quantitative cartilage morphometry at 3 Tesla: a pilot study for the osteoarthritis initiative," Magn Reson Med. 57(2), 448 (2007). S6. F. Eckstein, et al., "Two year longitudinal change and test-retest-precision of knee cartilage morphology in a pilot study for the osteoarthritis initiative," Osteoarthritis Cartilage. 15(11), 1326 (2007).

S7. E. Schneider, et al., "The osteoarthritis initiative (OAI) magnetic resonance imaging quality assurance methods and results," Osteoarthritis. Cartilage. 16(9), 994 (2008).

S8. J. G. Tamez-Pena, et al., "Unsupervised segmentation and quantification of anatomical knee features: data from the Osteoarthritis Initiative," IEEE Trans. Biomed. Eng 59(4), 1177 (2012).