Session Information
Session Type: ACR Poster Session C
Session Time: 9:00AM-11:00AM
Background/Purpose: The OMERACT ultrasound (US) Gout Task Force has defined four US elementary lesions to evaluate patients with gout: double contour (DC), aggregates, tophus and erosions. The objective of this study was to evaluate intra and inter-reader reliability of the US definitions of elementary lesions in gout and to assess the Influence of Sonographer Experience.
Methods: We conducted a cross-sectional study. Sixty-two sonographers from several countries and different degree of experience took part in an US reading exercise. All observers evaluated 50 ultrasound videos from patients with gout diagnoses. In addition, a group of 15 videos was displayed twice to assess intra-reader reliability. We evaluated the presence of the four elementary lesions described by OMERACT US Gout Task Force: double contour (DC), tophus, aggregates and erosion. Intra and Inter-reader reliability was calculated by the Cohen’s kappa coefficient and classified according to Landis and Koch criteria. Sonographers were stratiified according to US experience (defining High experience as at least ≥5 years of experience, ≥100 US assessments/month and ≥10 US in gout patients/month), evaluating differences in intra, inter – reader reliability and overall agreement. Bias-adjusted and prevalence-adjusted kappa (PABAK) was calculated to overcome prevalence bias in kappa estimates.
Results: A total of 3100 US assessment were performed. Prevalence of lesions were: Tophus (34%), Aggregates (29%), Erosions (22%) and DC (20%). The mean intra-reader values were good to excellent in all lesions (table 1). Mean Kappa inter-reader correlation coefficients, were fair for aggregates, moderate for tophus and erosions, and good for DC (Table 1). Adjusting for low-prevalence using PABAK estimates, inter-rater reliability increased to 0.42 (moderate), 0.49 (moderate), 0.69 (good) and 0.79 (good); respectively. There was not significant difference between experience and non-experience sonographers regarding to agreement and inter-rater reliability. Experience sonographers showed better intra-rater reliability for the detection of erosions (table 1).
Conclusion: The inter-rater reliability of the OMERACT US elementary lesions for gout is still a concern, especially in others than Double Contour. This results should be taken into account in the design of future multicenter studies.
Table 1. Agreement and kappa estimates stratified by evaluator experience
Group |
US experience [median, (p25-75)] |
US assessment per months [median, (p25-75)] |
US assessment in gout patients per months [median, (p25-75)] |
Reliability assessment (Intra or Inter rater) |
Aggregates |
DC |
Tophus |
Erosions |
||||
|
% |
k |
% |
k |
% |
k |
% |
k |
|||||
|
All Examiners (n=62) |
8 (4-10) |
65 (43-130) |
5 (2-8) |
Inter |
71% |
0.31 |
89% |
0.67 |
74% |
0.43 |
84% |
0.56 |
|
Intra |
83% |
0.62 |
95% |
0.85 |
85% |
0.69 |
93% |
0.77 |
||||
|
High experience (n=9) |
10 (8-12) |
130 (130-174) |
15 (10-20) |
Inter |
68% |
0.27 |
93% |
0.73 |
74% |
0.37 |
88% |
0.62 |
|
Intra |
83% |
0.64 |
95% |
0..84 |
84% |
0.61 |
99% |
0.94 |
||||
|
Low experience (n=53) |
8 (4-10) |
52 (43-130) |
4 (1-5) |
Inter |
71% |
0.31 |
89% |
0.67 |
74% |
0.43 |
84% |
0.56 |
|
Intra |
83% |
0.62 |
95% |
0.85 |
86% |
0.70 |
92% |
0.74 |
||||
Abbreviations: p25-75 – percentile 25 and 75; DC – double contour; k – Light’s kappa; % – proportion of observed agreement.
To cite this abstract in AMA style:
Cazenave T, Martire MV, Waimann CA, Bertoli A, Reginato A, Abril A, Ayala Ledesma EN, Bravo M, Cefferino C, Airoldi C, Saucedo C, Pineda C, Rodriguez Gil G, Urquiola C, Graf C, Sandobal C, Castillo Gallego MC, Troitiño C, Hernandez-Diaz C, Navarta D, Peiteado D, DIAZ M, Saaibi D, Colon Castillo HJ, Gutierrez M, Alvarez del Castillo Araujo AL, Sedano O, Alarcón E, Catay E, Mora C, De Miguel E, Fernández Castillo F, Marengo F, Aguilar G, Monjo I, Rosa J, Díaz Coto JF, Muñoz JS, Marin J, Santiago L, Alva M, Lima Gomes Ochtrop M, Guinsburg M, Benegas M, Santa Cruz MJ, Kohan P, Estrella N, Pera M, Tate P, Marcaida P, Py G, PAVAO R, Munoz-Louis R, Areny Micas R, Arape R, Ruta S, Gálvez Elkin MS, Urioste L, Saldarriaga Rivera L, VEGA-HINOJOSA O, Ventura L, Spindler WJ, Rengel Y, Quintero M, Rosemffet MG. Reliability of Ultrasound Elementary Lesions in Gout: Results from an Inter- and Intra-Reading International Multicenter Exercise By 62 Sonographers [abstract]. Arthritis Rheumatol. 2017; 69 (suppl 10). https://acrabstracts.org/abstract/reliability-of-ultrasound-elementary-lesions-in-gout-results-from-an-inter-and-intra-reading-international-multicenter-exercise-by-62-sonographers/. Accessed .« Back to 2017 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/reliability-of-ultrasound-elementary-lesions-in-gout-results-from-an-inter-and-intra-reading-international-multicenter-exercise-by-62-sonographers/