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Home / Equine Research Bank / J Vet Diagn Invest / IIB or not IIB, part 1: retrospective evaluation of Kenney-D...
Journal of veterinary diagnostic investigation : official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc2021; 34(2); 206-214; doi: 10.1177/10406387211062207

IIB or not IIB, part 1: retrospective evaluation of Kenney-Doig categorization of equine endometrial biopsies at a veterinary diagnostic laboratory and comparison with published reports.

Abstract: The Kenney-Doig scale is a histopathology categorization (grading) system often used as the standard for assessing endometrial disease and communicating prognostic fertility information for equine breeding prospects. We investigated how Kenney-Doig categories compared within the same institution and across different institutions to determine if observer variability may contribute to category frequencies. We conducted a retrospective analysis of all equine endometrial submission records between 1998 and 2018 at the Western College of Veterinary Medicine (WCVM) and Prairie Diagnostic Services (PDS). Of 726 biopsies, we found the following category distribution: 46 of 726 (6.3%) I, 307 of 726 (42.3%) IIA, 326 of 726 (44.9%) IIB, and 47 of 726 (6.5%) III. We also conducted a review of the literature and included 6 studies reporting Kenney-Doig category distributions. Chi-square analysis showed significant differences between the category distribution found at WCVM and PDS and the category distribution reported in the 6 studies. To account for differences in mare populations, individual category distributions were generated for 5 pathologists at the WCVM and PDS. The Fisher exact test among these 5 Kenney-Doig categories revealed significant differences in category tendencies, suggesting that observer variation affects the use of the scale. Our results suggest that there is a need for prospective inter-rater and intra-rater agreement studies of the repeatability of the Kenney-Doig scale.
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Publication Date: 2021-11-28 PubMed ID: 34841986PubMed Central: PMC8921822DOI: 10.1177/10406387211062207Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research discusses an investigation into the variability in use of the Kenney-Doig scale—a system for grading endometrial disease in horses.—by both different individuals and institutions. This investigation uncovered significant disparities, suggesting that the scale’s usage may be influenced by observer variation.

Research Methodology and Objectives

  • The goal of the study was to assess the consistency of the Kenney-Doig scale application, a grading system used to assess endometrial disease and predict fertility chances in horses.
  • With retrospective analysis of equine endometrial biopsy records from 1998-2018 from the Western College of Veterinary Medicine (WCVM) and Prairie Diagnostic Services (PDS), the researchers attempted to unveil any institutional or observer-related inconsistencies.

Results and Findings

  • From a total of 726 biopsies, the categorizations were as follows: 46 of 726 (6.3%) were classified as category I, 307 of 726 (42.3%) as category IIA, 326 of 726 (44.9%) as category IIB, and 47 of 726 (6.5%) as category III.
  • These results were then contrasted with six other studies that reported Kenney-Doig category distributions.
  • The researchers noticed significant differences between the categorization done at the WCVM and PDS and the distributions reported in the other six referenced studies.
  • Furthermore, when the study controlled for mare populations and created different category distributions for five separate pathologists at the WCVM and PDS, significant differences were again apparent.

Implications

  • The existence of an apparent observer variation in the use of the Kenney-Doig scale challenges its reliability as a measure of endometrial disease in horses.
  • This inconsistency suggests a need for further research via prospective inter-rater and intra-rater agreement studies to test the repeatability of the Kenney-Doig scale.
  • To ensure the Kenney-Doig scale’s continued use as a predictive system for equine breeding, a more standardized approach might be necessary, reducing observer bias and possible inconsistencies.

Cite This Article

APA
Westendorf J, Wobeser B, Epp T. (2021). IIB or not IIB, part 1: retrospective evaluation of Kenney-Doig categorization of equine endometrial biopsies at a veterinary diagnostic laboratory and comparison with published reports. J Vet Diagn Invest, 34(2), 206-214. https://doi.org/10.1177/10406387211062207

Publication

Journal of veterinary diagnostic investigation : official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc
ISSN: 1943-4936
NlmUniqueID: 9011490
Country: United States
Language: English
Volume: 34
Issue: 2
Pages: 206-214

Researcher Affiliations

Westendorf, Jane
  • Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
Wobeser, Bruce
  • Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
Epp, Tasha
  • Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.

MeSH Terms

  • Animals
  • Biopsy / veterinary
  • Endometrium
  • Female
  • Horse Diseases / diagnosis
  • Horse Diseases / pathology
  • Horses
  • Laboratories
  • Retrospective Studies

Conflict of Interest Statement

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

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Citations

This article has been cited 1 times.
  1. Westendorf J, Wobeser B, Epp T. IIB or not IIB, part 2: assessing inter-rater and intra-rater repeatability of the Kenney-Doig scale in equine endometrial biopsy evaluation.. J Vet Diagn Invest 2022 Mar;34(2):215-225.
    doi: 10.1177/10406387211062866pubmed: 34965793google scholar: lookup
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