The clinical diagnosis of equine sarcoids – Part 1: Assessment of sensitivity and specificity using a multicentre case-based online examination.

This research article focuses on assessing the accuracy of diagnosing equine sarcoids (ES), a skin condition in horses, based solely on clinical assessment. The study used an online exam to measure the sensitivity and specificity of diagnosing ES without histopathological confirmation. Despite a fairly high overall success rate, the study found that less experienced veterinarians, in particular, often misjudge the condition. The authors suggest creating a diagnostic tool to help improve the selection of lesions requiring biopsy.

Methodology and Study Design

• To evaluate the sensitivity, specificity, positive and negative predictive values of the clinical diagnosis of ES, the researchers created an online examination that featured 40 clinical cases.
• The cases included equine skin lesions which were histologically confirmed, 26 were ES and 14 were non-ES.
• The online examination provided a detailed standardised format of presentation. Details included a photograph of the lesion, the horse’s details, location of the lesion, progression of the lesion, any present additional skin lesions, previous treatments, and the response to those treatments.
• The study stressed that there was no relevant information intentionally left out in the examination that would impact the assessment of the lesions.

Participants and Evaluation Process

• The participants in the examination were divided into four groups: 14 ES experts, 39 board-certified equine specialists, 103 equine practitioners, and 25 novices.
• Participants were asked to categorise the cases as either ES or non-ES and assess their level of diagnostic confidence on a scale of 1 to 6 for each case.

Findings and Conclusions

• The study found that the overall success rate of participants was 82.0%, and the sensitivity and specificity were 83.3% and 79.6% respectively.
• The positive and negative predictive values in the tested population, with a 66% prevalence of ES, were 88.4% and 72.0% respectively.
• Interestingly, it was found that less experienced veterinarians often incorrectly judged the condition clinically, even when their level of diagnostic confidence was high.
• Based on these observations, the researchers recommend the development of a diagnostic tool. This should help with the selection of lesions requiring a biopsy more accurately, reducing the costs and morbidity associated with unnecessary diagnostic and therapeutic efforts.