# New Approaches to AI Methods for Screening Cardiomegaly on Chest Radiographs
## 3 Results
### Inter-Reader Agreement Assessment  
To assess the inter-reader agreement, we determined the average CTR or TCD values from three manual measurements (made by three independent radiologists) and from an automatic measurement. We then determined the ICC between this average and four measurement series (one automatic and three manual: 0, 1, and 2).  
For CTR calculated from manual and automatic segmentation, the ICC1 for mean vs. automatic was 0.954, ICC2 for mean vs. manual0 was 0.983, ICC3 for mean vs. manual1 0.990, and ICC4 for mean vs. manual2 was 0.963 (\(p\)-value for ICC1 vs. ICC2 was 0.013, for ICC1 vs. ICC3 was 0.0002, for ICC1 vs. ICC4 was 0.596, for ICC2 vs. ICC3 was 0.211, for ICC2 vs. ICC4 was 0.05, and for ICC3 vs. ICC4 was 0.001).  
For TCD calculated from manual and automatic segmentation, the ICC1 for mean vs. automatic was 0.972, ICC2 for mean vs. manual0 was 0.989, ICC3 for mean vs. manual1 0.994, and ICC4 for mean vs. manual2 was 0.971 (\(p\)-value for ICC1 vs. ICC2 was 0.03, for ICC1 vs. ICC3 was 0.0002, for ICC1 vs. ICC4 was 0.94, for ICC2 vs. ICC3 was 0.14, for ICC2 vs. ICC4 was 0.02, and for ICC3 vs. ICC4 was 0.0002).  
For CTR calculated from direct manual measurements and automatic segmentation, the ICC1 for mean vs. automatic was 0.956, ICC2 for mean vs. manual0 was 0.924, ICC3 for mean vs. manual1 0.980, and ICC4 for mean vs. manual2 was 0.971 (\(p\)-value for ICC1 vs. ICC2 was 0.16, for ICC1 vs. ICC3 was 0.06, for ICC1 vs. ICC4 was 0.31, for ICC2 vs. ICC3 was 0.001, for ICC2 vs. ICC4 was 0.02, and for ICC3 vs. ICC4 was 0.02, and for ICC3 vs. ICC4 was 0.40).  
For TCD calculated from direct manual measurements and automatic segmentation, the ICC1 for mean vs. automatic was 0.975, ICC2 for mean vs. manual0 was 0.950, ICC3 for mean vs. manual1 0.950, and ICC4 for mean vs. manual2 was 0.978 (\(p\)-value for ICC1 vs. ICC2 was 0.09, for ICC1 vs. ICC3 was 0.09, for ICC1 vs. ICC4 was 0.047, and for ICC3 vs. ICC4 was 0.046).  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Cardiomegaly Definition Based on CMR** & **Method of Measurements** & **AUC** \\ \hline \multirow{4}{*}{Both elevated LVEDV and enlarged LVM} & Manual reading & 0.795 \\ \cline{2-3}  & Manual segmentation & 0.775 \\ \cline{2-3}  & Automatic segmentation & 0.761 \\ \hline \multirow{4}{*}{Both elevated LVEDV/BSA and enlarged LVM/BSA} & Manual reading & 0.793 \\ \cline{2-3}  & Manual segmentation & 0.745 \\ \cline{2-3}  & Automatic segmentation & 0.734 \\ \hline \multirow{4}{*}{Elevated LVEDV} & Manual reading & 0.892 \\ \cline{2-3}  & Manual segmentation & 0.899 \\ \cline{2-3}  & Automatic segmentation & 0.916 \\ \hline \multirow{4}{*}{Enlarged LVM} & Manual reading & 0.808 \\ \cline{2-3}  & Manual segmentation & 0.745 \\ \cline{2-3}  & Automatic segmentation & 0.731 \\ \hline \multirow{4}{*}{Elevated LVEDV/BSA} & Manual reading & 0.922 \\ \cline{2-3}  & Manual segmentation & 0.902 \\ \cline{2-3}  & Automatic segmentation & 0.928 \\ \hline \multirow{4}{*}{Enlarged LVM/BSA} & Manual reading & 0.793 \\ \cline{2-3}  & Manual segmentation & 0.745 \\ \cline{2-3}  & Automatic segmentation & 0.734 \\ \hline \hline \end{tabular} Abbreviations: BSA—body surface area; CMR—cardiac magnetic resonance; LVEDV—left ventricle end–diastolic volume; LVM—left ventricular mass; TCD—transverse cardiac diameter.  
\end{table}
Table 4: Results of receiver operating characteristic analysis for transverse cardiac diameter.  
The inter-variability segmentation metrics between the two radiologists are summarized in Table 5, which presents the Dice similarity coefficients and Hausdorff distances for the lung and heart. The table highlights the mean, standard deviation, minimum, and maximum values for each comparison, providing a comprehensive view of the segmentation consistency. Statistical analysis revealed no significant differences across the comparisons[PERSON]