## 3 Results
### Discussion  
Accurate and timely identification of viral pathogens is critical for guiding patient management, implementing infection control measures, and informing public health strategies. To our knowledge, this is the first study to compare the performance of the Bioneer \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Target** & **CIA*/PCR\({}^{\dagger}\)** & **CIA*/PCR\({}^{\dagger}\)** & **CIA*/PCR\({}^{\ddagger}\)** & **CIA*/PCR\({}^{\ddagger}\)** & **PPA\({}^{\ddagger}\)** & **NPA\({}^{\lx@sectionsign}\)** & **OPA\({}^{\dagger}\)** & **Cohens\({}^{\prime}\)** \\  & \(-/-\) & +/\(-\) & \(-\)/+ & +/+ & (95\% CI) & (95\% CI) & (95\% CI) & **(95\% CI)** & **Kappa** \\ \hline Adenovirus & 51 & 12 & 0 & 0 & 0 & 100.0 & 80.95 (0.000) & 0.000 \\ \hline Rotavirus & 52 & 10 & 0 & 1 & 90.9 & 100.0 & \
\begin{tabular}{c} 84.13 \\ (\(-\)0.109 to 0.392) \\ \end{tabular} & 0.142 \\ \hline Norovirus & 51 & 3 & 8 & 1 & 25.0 & 86.4 &
\begin{tabular}{c} 82.54 \\ (\(-\)0.203 to 0.348) \\ \end{tabular} & 0.072 \\ \hline Sapovirus & NA/62 & NA & NA & NA/1 & / & / & / & / \\ \hline Astrovirus & NA/63 & 0 & 0 & 0 & / & / & / \\ \hline \hline \end{tabular}  
* Note: CIA* (chromatographic immunoassay): JustCheck Norovirus; AcroBiotech Rota/Adenovirus; PCR\({}^{\ddagger}\): Bioneer AcroPower Diarrhea V16V2 Real-Time RT-PCR; PPA\({}^{\ddagger}\) (positive percent agreement), NPA\({}^{\lx@sectionsign}\) (negative percent agreement), OPA\({}^{\dagger}\)\({}^{\dagger}\) (overall percent agreement).  
\end{table} 
Table 2: Human stool co-testing with CIA and RT-PCR. AccuPower Diarrhea V1&V2 RT-PCR with a chromatographic immunoassay for detecting major gastrointestinal viruses in stool specimens. The RT-PCR multiplex method, when paired with advanced nucleic acid extraction systems like the ExiPrep(tm)48 Dx, Bioneer, offers a simple, automated, and user-friendly solution for pathogen detection in clinical settings. Our results highlight significant discrepancies between the two methods, emphasizing the diagnostic limitations of CIA and the potential advantages of RT-PCR in specific clinical (e.g., immunosuppression) and diagnostic scenarios (e.g., cross-reactivity in CIA). The overall findings demonstrate the superior sensitivity and specificity of RT-PCR compared to CIA, particularly for norovirus and adenovirus detection. For norovirus, CIA had a low PPA of 25%, indicating that it missed 75% of norovirus-positive cases identified by RT-PCR. Additionally, the observed false positive rate with CIA highlights its limited reliability for this pathogen. These results align with the existing literature, suggesting that norovirus detection is challenging with rapid antigenic tests, especially in low-viral-load cases or during outbreaks, where accurate results are critical for infection control and management. Adenovirus detection by CIA showed poor agreement with RT-PCR, with 12 false positives reported and a PPA of 0%. This lack of sensitivity raises concerns about the clinical utility of CIA for diagnosing adenovirus gastroenteritis, particularly in immunocompromised patients, where timely and accurate identification is crucial. While the NPA for adenovirus was 100%, the false positives undermine CIA's reliability as a standalone diagnostic tool. Rotavirus detection presented a relatively better performance with CIA, achieving a PPA of 90.9% and an OPA of 84.13%. However, the presence of false positives (15.8%) highlights the need for confirmatory testing, especially in cases where clinical presentation does not align with CIA results. The higher agreement observed for rotavirus suggests that CIA may still hold some value in resource-limited settings for this pathogen, but its results should be interpreted cautiously. In addition, it is important to mention that six samples gave a simultaneous positive result for rotavirus and adenovirus (all were RT-PCR-negative), and four samples gave a positive CIA result for all three viruses tested (of which only one was RT-PCR-positive for norovirus).