Format

Send to

Choose Destination
Clin J Am Soc Nephrol. 2009 Mar;4(3):567-71. doi: 10.2215/CJN.05331008. Epub 2009 Mar 4.

Interobserver reliability of urine sediment interpretation.

Author information

1
Department of Medicine, Division of Nephrology, St Michael's Hospital, Toronto, ON, Canada. ron.wald@utoronto.ca

Abstract

BACKGROUND AND OBJECTIVES:

Urine sediment interpretation is frequently used in the evaluation of patients with kidney disease. There has been no systematic evaluation of the reliability of this diagnostic maneuver.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS:

Digital photographs of urine sediment images were acquired from 165 consecutive patients being evaluated by the nephrology consultation service at a tertiary care hospital. Urine sediment images of 100 patients were randomly selected; 86 patients had images that were deemed to be of sufficient quality, and one image per patient was chosen for inclusion in an internet-based questionnaire. For each image, the presence or absence of 14 potential urinary structures was ascertained. Ten nephrologists (senior readers [n = 3]: >10 yr of experience; intermediate readers [n = 3]: 1 to 10 yr of experience; and junior readers [n = 4]: first year of practice) completed the questionnaire. For each urinary structure, we measured the rate of complete agreement among the readers as well as the kappa statistic as a marker of agreement beyond chance.

RESULTS:

Unanimous agreement was highest (79.1%) regarding the presence of broad and fatty casts and poorest (31.4%) for the identification of dysmorphic red blood cells and white blood cells. Interobserver agreement was best for squamous epithelial cells (kappa = 0.54) and hyaline casts (kappa = 0.52) and worst for transitional epithelial cells (kappa = 0.14) and fatty casts (kappa = 0.06). When assessed within strata of physician experience, interobserver agreement was not associated with seniority.

CONCLUSIONS:

Nephrologists achieved slight to moderate agreement in the identification of structures that are commonly observed in the urine sediment.

PMID:
19261816
PMCID:
PMC2653656
DOI:
10.2215/CJN.05331008
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center