Reproducibility of the scleroderma pattern assessed by wide-field capillaroscopy in subjects suffering from Raynaud's phenomenon.

Objectives: The aim of this work was to study inter- and intra-observer agreement for the diagnosis of scleroderma pattern by wide-field capillaroscopy. Methods: Images were taken from 50 patients known to have SSc and 50 controls consulting for RP who did not have SSc. These images were rated simultaneously by 11 experienced vascular medicine physicians as scleroderma pattern or not. Two weeks later, 7 of the 11 observers again rated the same images. Results: Inter-observer agreement was almost perfect between the 11 observers (κ 0.86 ± 0.01), and the proportion of concordant observations was 79% (70-87). When each observer was compared with the reference, agreement was also almost perfect: κ coefficient 0.92 ± 0.03 and proportion of concordant observations 79% (70-87). Intra-observer agreement was also almost perfect: median κ coefficient 0.94 (0.78-0.96) and median proportion of concordant observations 97% (89-98). Conclusion: Excellent inter- and intra-observer agreement was obtained in experienced vascular physicians for the diagnosis of capillaroscopic landscape by wide-field nailfold capillary microscopy.

Reproducibility of capillaroscopic classifications of systemic sclerosis: results from the SCLEROCAP study.

Objectives: Subgroups of capillaroscopic scleroderma landscape have been correlated with stages of SSc: two groups for Maricq's classification (slow and active), and three for Cutolo's classification (early, active and late). We report inter- and intra-observer agreement for these classifications as a preliminary step in the multicentre prospective SCLEROCAP study, which aims to assess the classification and single capillaroscopic items as prognostic tools for SSc. Methods: SCLEROCAP included 385 patients. Agreement was studied in the first 100 patients, who were independently rated twice by two observers, blind to patients' characteristics; 30 of the patients were rated once by six observers. After consensus meetings, these ratings were held again. Kappa and intraclass correlation coefficients were used to assess agreement. Results: Interobserver agreement on 100 patients was moderate for Maricq and Cutolo classifications [κ 0.47 (0.28, 0.66) and 0.49 (0.33, 0.65), respectively], and became substantial after consensus meetings [0.64 (0.50, 0.77) and 0.69 (0.56, 0.81)]. Intra-observer agreement between two observers was moderate to substantial: κ 0.54 (0.33, 0.75) and 0.70 (0.57, 0.83) for Maricq's classification; 0.57 (0.38, 0.77) and 0.76 (0.65, 0.87) for Cutolo's. Thirty patients were rated once by each of six observers, and agreement was moderate to substantial: κ 0.57 ± 0.10 (Maricq) and 0.61 ± 0.12 (Cutolo). Agreement was substantial for bushy, giant capillaries and microhaemorrhages, moderate for capillary density and low for oedema, disorganization and avascular areas. Conclusion: The moderate reproducibility of Maricq and Cutolo classifications might hamper their prognostic value in SSc patients. Consensus meetings improve reliability, a prerequisite for better prognostic performances. A focus on giant capillaries, haemorrhages and capillary density might be more reliable.