Abstract In order to relate histopathological findings of the kidney in systemic vasculitis to renal outcome, scoring of various morphological parameters is neces-.
Nephrol Dial Transplant (1996) 11: 1989-1995
Nephroloqy Dialysis Transplantation
Original Article
The renal histopathology in systemic vasculitis: an international survey study of inter- and intra-observer agreement I. M. Bajema1'2, E. C. Hagen3, B. E. Hansen4, J. Hermans4, L. H. Noel5, R. Waldherr6, F. Ferrario7, F. J. van der Woude8 and J. A. Bruijn1 Departments of 'Pathology, Nephrology and 4Medical Statistics, Leiden University, and Leiden University Hospital, The Netherlands; 3Eemland Hospital 'Lichtenberg', Amersfoort, The Netherlands; 'Department of Nephrology, Hopital Necker, Paris, France; 6Department of Pathology, University of Heidelberg, Germany; 7Department of Nephrology, Ospedale San Carlo Borromeo, Milan, Italy; 8Vth Medical Department, Medical Faculty Mannheim, University of Heidelberg, Germany
Abstract In order to relate histopathological findings of the kidney in systemic vasculitis to renal outcome, scoring of various morphological parameters is necessary. Therefore, we conducted a standardization study for evaluating renal biopsies from patients with systemic vasculitis. Four experienced renal pathologists from four European centres joined in the study. A scoring protocol was devised that required the observers to score an extensive number of histopathological lesions either quantitatively (as a percentage of the total number of glomeruli) or dichotomously (on a present/absent scale). Twenty renal biopsies were scored individually by all the observers, from which the inter-observer variability was analysed. Ten randomly chosen biopsies were scored again, in order to obtain the intra-observer variability. For inter-observer agreement, the evaluation of the quantitative variables was satisfactory for both rounds (0.55^Kendall's H^0.95 and 0 . 5 9 ^ ^ 0 . 9 6 , respectively, with all P
1E ver
-/•
wit
Thrombo»l»
-/+
tho
eo*mophB»
HyaSnosii
uh
nautropftfli mononuofctar oalb
-/•
'S3
Sderoitt Necrotit V w a a U n n InflXnrt* OUtyp* of W»ra«a
s.
j+
•ra arteriw prttent
z
ber
Artarin
rosis
logists
(
a:
U
x:
Z
on B
_, £
o
1
ra
DO
— r^i
O
o
psy
-o
o ca
tal
a.
. Raw
Kappa values for the rank concordance of the dichotomous data were generally poor (i.e. below 0.30) during the first and the second observation round (Table 3). Only for interstitial and intratubular infiltrates and for tubular atrophy there appeared to be some consensus among the observers at both occasions.
5U1O
Inter-observer variation, dichotomous data
No.
C
