Validity and sensitivity to change of the semi-quantitative OMERACT ultrasound scoring system for tenosynovitis in patients with rheumatoid arthritis.
OBJECTIVE
The aim was to evaluate the metric properties of the semi-quantitative OMERACT US scoring system vs a novel quantitative US scoring system for tenosynovitis, by testing its intra- and inter-reader reliability, sensitivity to change and comparison with clinical tenosynovitis scoring in a 6-month follow-up study.


METHODS
US and clinical assessments of the tendon sheaths of the clinically most affected hand and foot were performed at baseline, 3 and 6 months in 51 patients with RA. Tenosynovitis was assessed using the semi-quantitative scoring system (0-3) proposed by the OMERACT US group and a new quantitative US evaluation (0-100). A sum for US grey scale (GS), colour Doppler (CD) and pixel index (PI), respectively, was calculated for each patient. In 20 patients, intra- and inter-observer agreement was established between two independent investigators. A binary clinical tenosynovitis score was performed, calculating a sum score per patient.


RESULTS
The intra- and inter-observer agreements for US tenosynovitis assessments were very good at baseline and for change for GS and CD, but less good for PI. The smallest detectable change was 0.97 for GS, 0.93 for CD and 30.1 for PI. The sensitivity to change from month 0 to 6 was high for GS and CD, and slightly higher than for clinical tenosynovitis score and PI.


CONCLUSIONS
This study demonstrated an excellent intra- and inter-reader agreement between two investigators for the OMERACT US scoring system for tenosynovitis and a high ability to detect changes over time. Quantitative assessment by PI did not add further information.
Copenhagen Center for Arthritis Research (COPECARE), Center for Rheumatology and Spine Diseases, Rigshospitalet, Glostrup ammitz7@gmail.com.|Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.
Mads
M
Ammitzbøll-Danielsen
Copenhagen Center for Arthritis Research (COPECARE), Center for Rheumatology and Spine Diseases, Rigshospitalet, Glostrup.|Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.
Mikkel
M
Østergaard
Department of Rheumatology, Hospital General Universitario Gregorio Marañón and Universidad Complutense, Madrid, Spain.
Esperanza
E
Naredo
Copenhagen Center for Arthritis Research (COPECARE), Center for Rheumatology and Spine Diseases, Rigshospitalet, Glostrup.
Lene
L
Terslev
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018501:Antirheumatic Agents / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000000981:diagnostic imaging* / Q000188:drug therapy; D005260:Female; D005534:Foot Diseases / Q000150:complications / Q000000981:diagnostic imaging / Q000188:drug therapy; D005938:Glucocorticoids / Q000627:therapeutic use; D006225:Hand / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011594:Psychometrics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013583:Synovial Membrane / Q000502:physiology; D013710:Tendons / Q000502:physiology; D013717:Tenosynovitis / Q000150:complications / Q000000981:diagnostic imaging*; D018615:Ultrasonography, Doppler, Color; D055815:Young Adult
D018501:Antirheumatic Agents; D005938:Glucocorticoids
OMERACT; reliability; rheumatoid arthritis; scoring system; tenosynovitis; ultrasonography