How reliable are ultrasound measurements of renal length in adults?
Ablett MJ; Coulthard A; Lee RE; Richardson DL; Bellas T; Owen JP; Keir MJ; Butler TJ Department of Radiology, Royal Victoria Infirmary, Newcastle upon Tyne, UK. Ultrasound assessment of patients with renal impairment commonly includes measurement of bipolar renal length. Reduction in length is considered to indicate chronic renal disease and is a factor in deciding whether to proceed to renal biopsy. To date, no published data are available on interobserver and intraobserver variation in sonographic renal length measurement in adults. Bilateral renal lengths were measured in 20 adult subjects, with no history of renal disease, by three experienced operators, on two separate occasions. Limits of agreement for replicate measurements by each ultrasonographer and for replicate measurements by each pair of ultrasonographers were determined. Values of repeatability (a measure of intraobserver variation) and reproducibility (a measure of interobserver variation) were calculated for all renal
