Interobserver reproducibility in reporting on renal cortical scintigraphy in children: a large collaborative study.
OBJECTIVE
To evaluate the interobserver reproducibility in reporting on technetium-99m (99mTc) dimercaptosuccinic acid (DMSA) scan in children.


METHODS
Sixty 99mTc-DMSA scans, issued from three centres, were distributed by e-mail to nuclear medicine physicians from the five continents interested in paediatric nuclear medicine. Observers had to choose, for each kidney, among four answers: normal, abnormal, equivocal or poor quality. An additional question was the location of the lesion if any: upper part, mid part, lower part. The responses had to be returned by e-mail.


RESULTS
Sixty-one observers, with an experience of approximately five or more 99mTc-DMSA/month, contributed to the study. Median agreement was 93%. The agreement was less than 80% in 29 kidneys (24%) but only in 13% (16 kidneys) was there disagreement between normality and abnormality, the remaining cases being related to 'equivocal' responses. Disagreement was mainly related to the following patterns: (i) normal variants: pear-shaped kidney, hypoactive poles contrasting with important parenchymal mass, triangular kidney, unusual shape of the columns of Bertin; (ii) congenital abnormalities: hydronephrosis, normal duplex kidney; (iii) small defects.


CONCLUSIONS
Interobserver reproducibility can be considered as good among a wide number of observers from the five continents. Disagreement among observers could be reduced by taking the normal variants into account.
Tondeur
Marianne C
MC
Department of Radioisotopes, CHU St Pierre, Brussels, Belgium. Marianne_Tondeur@stpierre-bru.be
De Palma
Diego
D
Roca
Isabel
I
Piepsz
Amy
A
Ham
Hamphrey H
HH
D002648:Child; D015902:Gamma Cameras; D006801:Humans; D006869:Hydronephrosis / Q000000981:diagnostic imaging; D007391:International Cooperation; D007672:Kidney Cortex / Q000002:abnormalities / Q000000981:diagnostic imaging*; D007674:Kidney Diseases / Q000000981:diagnostic imaging; D015588:Observer Variation; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D019783:Technetium Tc 99m Dimercaptosuccinic Acid
D019275:Radiopharmaceuticals; D019783:Technetium Tc 99m Dimercaptosuccinic Acid