Reliability of body condition scoring using the Rabbit Size-O-Meter in companion rabbits (Oryctolagus cuniculus)

Area of Science:

• Veterinary Medicine
• Animal Science
• Comparative Physiology

Background:

• Body condition scoring systems are crucial for monitoring companion animal adiposity.
• Existing systems lack validation for rabbits, a common pet species.
• Assessing the reliability of the Rabbit Size-O-Meter (RSOM) scale is essential for accurate rabbit health assessments.

Purpose of the Study:

• To evaluate the inter- and intra-rater reliability of the five-point Rabbit Size-O-Meter (RSOM) scale.
• To assess the scale's consistency across different rater experience levels (veterinary professionals, students, laypersons).
• To investigate the influence of rabbit demographics (age, sex, breed) on body condition scores.

Main Methods:

• 205 rabbits were scored using the RSOM by three distinct rater groups.
• Inter-rater reliability was quantified using Krippendorff's alpha.
• Intra-rater reliability was assessed using Cohen's kappa, with a subset of 10 rabbits re-scored.

Main Results:

• Overall inter-rater reliability was poor (α = 0.58), though moderate among veterinary professionals (α = 0.72).
• Agreement decreased significantly with less experienced raters (students, laypersons).
• Intra-rater reliability demonstrated substantial to almost perfect agreement (κ = 0.69‒0.90).

Conclusions:

• The RSOM exhibits high consistency when used by the same individual (intra-rater reliability).
• Significant variability exists between different individuals scoring rabbit body condition (inter-rater reliability).
• Recommendations include refining the RSOM and validating it against objective adiposity measures.