## 3 Results
### Efficacy of IRT in Assessing the Temperature of the Horse's Eyes  
The temperatures of the three ROIs are shown in Table 3. The medial canthus had the highest temperature in the three areas of both eyes. In addition, in the medial canthus region, the temperature of the center area (2 \(\times\) 2 pixels) in the 4 \(\times\) 4 pixels was higher (by approximately 0.16 \({}^{\circ}\)C-0.20 \({}^{\circ}\)C) than that of the 4 \(\times\) 4 pixels.  
Table 3 shows that the RMSE and QRMSE (\(p\) < 0.0001) of the three ROIs in the horse's eyes for each instance of RT had values closer to 0, indicating better results. The RMSE and QRMSE before correction had a value of 1.6 or more (Table 3). As shown in Table 4, after correction, they were less than 0.4 to 1.1, respectively. Therefore, the RMSE and QRMSE in 2 \(\times\) 2 pixels displayed the best results in the medial canthus after statistical bias correction.  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**(\(n\) = 176)**} & \multicolumn{4}{c}{ET} & \multirow{2}{*}{**RT**} & \multirow{2}{*}{**HR**} & \multirow{2}{*}{**RR**} \\ \cline{2-2} \cline{6-8}  & & & & & & & \\ \hline Mean & 34.86 & 35.33 & 34.15 & 37.7 & 37 & 23.67 \\ SD & 1.01 & 1.01 & 1.02 & 0.29 & 11.33 & 5.75 \\ Min & 29.7 & 32.5 & 29.0 & 37 & 21 & 12 \\ Max & 37.1 & 38.2 & 36.7 & 38.2 & 60 & 36 \\ CV (\%) & 2.18 & 2.14 & 2.25 & 1.01 & 31.25 & 36.98 \\ CC & 0.3048 & 0.3392 & 0.2073 & 1.00 & 0.088 & 0.032 \\ \hline \hline \end{tabular} LC, lacarimal sac; MC, medial canthus; LC, lateral canthus; SD, standard deviation; CV (\%), coefficient variation; CC, correlation coefficients.  
\end{table}
Table 2: Correlation between eye temperature (ET, \({}^{\circ}\)C: left and right) and heart rate (HR, beat/min), and respiratory rate (RR, cycles/min) for each instance of rectal temperature (RT, \({}^{\circ}\)C) recorded in 176 horses.  
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Total (\(n\) = 176)**} & \multicolumn{4}{c}{**4 \(\times\) 4 Pixels**} & \multicolumn{4}{c}{**2 \(\times\) 2 Pixels**} \\ \cline{2-10}  & **Max (\({}^{\circ}\)C)** & **RMSE** & **QRMSE** & **Mean (\({}^{\circ}\)C)** & **RMSE** & **QRMSE** & **Mean (\({}^{\circ}\)C)** & **RMSE** & **QRMSE** \\ \hline \multirow{2}{*}{Left} & LS & 35.10 \(\pm\) 1.02 & 2.49 & 2.35 & 34.94 \(\pm\) 1.05 & 2.65 & 2.52 & 35.05 \(\pm\) 1.05 & 2.60 & 2.47 \\  & MC & 35.72 \(\pm\) 0.97 & 1.84 & 1.63 & 35.40 \(\pm\) 1.05 & 2.14 & 1.96 & 35.56 \(\pm\) 1.03 & 1.92 & 1.75 \\  & LC & 34.42 \(\pm\) 0.96 & 3.32 & 3.20 & 34.16 \(\pm\) 1.07 & 3.53 & 3.42 & 34.28 \(\pm\) 1.04 & 3.46 & 3.35 \\ \hline \multirow{2}{*}{Right} & LS & 35.08 \(\pm\) 0.92 & 2.56 & 2.50 & 34.90 \(\pm\) 0.99 & 2.71 & 2.58 & 35.00 \(\pm\) 0.98 & 2.67 & 2.54 \\  & MC & 35.78 \(\pm\) 0.92 & 1.70 & 1.62 & 35.43 \(\pm\) 1.01 & 2.04 & 1.84 & 35.63 \(\pm\) 0.96 & 1.89 & 1.69 \\  & LC & 34.56 \(\pm\) 0.97 & 3.27 & 3.23 & 34.36 \(\pm\) 1.01 & 3.45 & 3.34 & 34.46 \(\pm\) 1.01 & 3.41 & 3.30 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Maximum, mean temperature, root mean square error (RMSE), and quantile RMSE (QRMSE) of the three ROIs in the horse’s eyes for each rectal temperature (RT, \({}^{\circ}\)C).