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Journal of veterinary diagnostic investigation : official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc2021; 34(2); 215-225; doi: 10.1177/10406387211062866

IIB or not IIB, part 2: assessing inter-rater and intra-rater repeatability of the Kenney-Doig scale in equine endometrial biopsy evaluation.

Abstract: Inter- and intra-rater variability negatively affects the reliability of various histopathology grading scales used as prognostic aids in human and veterinary medicine. The Kenney-Doig categorization (grading) scale, which is used to associate equine endometrial histologic lesions with prognostic estimation of a broodmare's reproductive potential, has not been evaluated for inter- or intra-rater variability, to our knowledge. To assess whether the Kenney-Doig system produces reliable results among observers, 8 pathologists, all with American College of Veterinary Pathologists certification, were recruited to blindly categorize the same set of 63 digital equine endometrial biopsy slides as well as to re-evaluate anonymously 21 of 63 of these slides at a later time. Cohen kappa values for pairwise comparison of final Kenney-Doig categories were -0.05 to 0.46 (unweighted) and 0.08-0.64 (weighted), with an average Light kappa of 0.19 (unweighted) and 0.36 (weighted) across all 8 pathologists, 0.14 (unweighted) and 0.33 (weighted) for pathologists at different institutions, and 0.22 (unweighted) and 0.46 (weighted) for pathologists at the same institution. Intra-class correlations measuring intra-rater agreement were 0.12-0.77 with an average of 0.55 for all 8 pathologists. We found that only slight-to-moderate inter-rater agreement and poor-to-good intra-rater agreement was produced by 8 pathologists using the Kenney-Doig scale, suggesting that the system is subject to significant observer variability and care should be taken when communicating Kenney-Doig categories to submitting clinicians with emphasis on the quality of endometrial lesions present instead of the category and associated expected foaling rate.
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Publication Date: 2021-12-29 PubMed ID: 34965793PubMed Central: PMC8921799DOI: 10.1177/10406387211062866Google Scholar: Lookup
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  • Journal Article

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 researchers tested the reliability of the Kenney-Doig grading system, used to rate equine endometrial lesions for predicting a broodmare’s reproductive potential. Their findings indicate that different pathologists’ ratings using this scale can vary significantly, suggesting a need for cautious communication regarding the system’s categories and expected foaling rate.

Study Objective

  • The study aimed to test the reliability and consistency of the Kenney-Doig scale which is used in veterinary medicine to assess equine endometrial lesions. This rating system serves as a prognostic tool estimating the reproductive potential of a broodmare. The reliability of this system has not been evaluated before in terms of consistency across different raters (inter-rater) or consistency of the same rater over time (intra-rater).

Methodology

  • Eight pathologists, all certified by the American College of Veterinary Pathologists, were recruited for this study. They were asked to provide blind categorization using the Kenney-Doig scale on a set of 63 digital equine endometrial biopsy slides.
  • In order to evaluate intra-rater variability, 21 slides from the original set were re-evaluated by the same pathologists at a later stage.
  • The agreement among the pathologists for the initial and repeat assessments was then measured using Cohen kappa values and Intra-class correlations.

Key Findings

  • The Cohen kappa values indicated broad variation in inter-rater compatibility, ranging from -0.05 to 0.46 (unweighted) and 0.08-0.64 (weighted).
  • The consistency between the results of the same pathologist at different times (intra-rater consistency) as evaluated by intra-class correlations, ranged from 0.12 to 0.77, with an average of 0.55 for all eight pathologists.
  • These findings suggest that there is only slight to moderate agreement between different observers, and poor to good agreement when the same observer rates at different times.

Conclusion

  • The results indicate a high degree of variability in the use of the Kenney-Doig scale, pointing to a risk of inconsistency in its application.
  • This highlights the need for caution when interpreting and communicating findings using this system, with a recommendation to focus more on the quality of endometrial lesions instead of the category and its associated expected foaling rate.

Cite This Article

APA
Westendorf J, Wobeser B, Epp T. (2021). 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, 34(2), 215-225. https://doi.org/10.1177/10406387211062866

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: 215-225

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
  • Horses
  • Humans
  • Observer Variation
  • Reproducibility of Results

Conflict of Interest Statement

Declaration of conflicting interests: 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. Zdrojkowski Ł, Pawliński B, Skierbiszewska K, Jasiński T, Domino M. Assessment of Connective Tissue in the Equine Uterus and Cervix: Review of Clinical Impact and Staining Options. Animals (Basel) 2024 Jan 3;14(1).
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