\begin{table*}[ht]
\centering
\caption{
\textbf{State-of-the-art comparisons} using DenseNet-121, ResNet-18, and ResNet-50 as backbones.
We re-implement the methods on the datasets and report the mean accuracy across all the domains. The best results are in \textbf{bold. }Our results are averaged over five runs. Our method performs the best consistently with the highest performance improvement.
} 
\centering
    \resizebox{1\columnwidth}{!}{%
        \setlength\tabcolsep{4pt} 
\begin{tabular}{lllllll}
\toprule
& \multicolumn{3}{c}{\textbf{Messidor}}     & \multicolumn{3}{c}{\textbf{Fetal-8}} \\ 
\cmidrule(lr){2-4} \cmidrule(lr){5-7}
\quad \textbf{Methods} & DenseNet-121 & ResNet-18 & ResNet-50 & DenseNet-121 & ResNet-18 & ResNet-50 \\ \midrule

\quad ERM &  52.2 & 53.1 & 52.1 & 81.6 & 84.3 & 83.6 \\


\midrule
\multicolumn{7}{l}{\textit{Parametric}} \\
\quad Tent \cite{wang2021tent} 
&  44.7 \scriptsize{$\pm$0.4} & 43.9 \scriptsize{$\pm$0.5} & 40.0 \scriptsize{$\pm$0.5}& 73.0 \scriptsize{$\pm$0.6} & 70.3 \scriptsize{$\pm$0.4} & 80.1 \scriptsize{$\pm$0.5} \\

\quad SHOT \cite{liang2020we} 
& 47.4 \scriptsize{$\pm$0.4} & 51.6 \scriptsize{$\pm$0.5} & 51.9 \scriptsize{$\pm$0.6} & 69.8 \scriptsize{$\pm$0.7} & 70.1 \scriptsize{$\pm$0.4} & 72.4 \scriptsize{$\pm$0.7}  \\

\quad ShotIM \cite{liang2020we} 
& 47.5 \scriptsize{$\pm$0.4}& 51.8 \scriptsize{$\pm$0.5}& 46.0 \scriptsize{$\pm$0.6}& 68.9 \scriptsize{$\pm$0.7}& 69.9 \scriptsize{$\pm$0.5}& 72.0 \scriptsize{$\pm$0.7}\\

 \midrule
\multicolumn{7}{l}{\textit{Non-Parametric}}\\

\quad T3A \cite{iwasawa2021test}
& 51.6 \scriptsize{$\pm$0.4}& 51.8 \scriptsize{$\pm$0.3} & 51.6 \scriptsize{$\pm$0.3}& 82.4 \scriptsize{$\pm$0.3}& 71.8 \scriptsize{$\pm$0.4}& 85.6 \scriptsize{$\pm$0.3}\\


 \toprule
\quad {\textit{\textbf{TNN (Ours)}}}
& \textbf{53.1}  \scriptsize{$\pm$0.2} & \textbf{53.8} \scriptsize{$\pm$0.2} & {\textbf{53.9}} \scriptsize{$\pm$0.2} & \textbf{83.3 }\scriptsize{$\pm$0.2} & 72.7 \scriptsize{$\pm$0.2} & \textbf{86.1} \scriptsize{$\pm$0.2} \\

\bottomrule
\end{tabular}
}

\label{table:all_datasets}
\end{table*}
