## 4 Discussion  
Challenges for children with CIs are increasing in everyday listening scenarios. Indeed, these determine a risk source for HoH children due to their role in the degradation of speech understanding related to the presence of reverberation and noise, as highlighted also by [PERSON] et al. [33]. The main outcomes of this work corroborate the few available similar studies. The presented outcomes, however, only consider the effects of noise and the presence of different face masks as competitive factors for speech understanding. As far as the exclusive effect of noise is concerned (i.e., no mask effect is considered), this work highlighted that speech intelligibility for children with CIs degrades when SNR decreases. In particular, it shifts from about 90% to about 80% to about 62% under the +10 dB SNR, +5 dB SNR, and 0 dB SNR conditions, respectively. [PERSON] et al. [33] found that children with CIs need an average SNR of about 10 dB to reach 50% speech intelligibility. This result slightly differs from that of the present study; however, it is possible to compare them, as they are dependent on the type of noise considered in the experiments, and that differed between the two. Indeed, [PERSON] et al. [33] considered a speech-shaped artificial noise, whereas in this work it has been considered a real classroom noise with a degree of informative content. Furthermore, the compared study of [PERSON] et al. [33] presents a high variability in the results. Concerning the effect of face masks on speech intelligibility, [PERSON] et al. [34] found that both HoH and TH listeners experienced difficulties in the speech communication process, which is referred to speaking as well as to listening, due to wearing a mask or communicating under noisy conditions. This finding is corroborated by the presented experiments, as HoH listeners in the EG experienced a higher listening difficulty compared to the participants with TH in the CG. Indeed, this difference was statistically significant  
Figure 4: Mean listening difficulty scores and related standard errors reported as error bars. Black circles (\(\bullet\)) show the Experimental Group (EG) results; empty circles (\(\Box\)) show the Control Group (CG) results. Values on the y-axis correspond to the degrees of perceived difficulty, i.e., 1—no difficulty at all, 2—very low difficulty, 3—slight difficulty, 4—high difficulty, 5—very high difficulty. \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **No Mask** & **Mask 1** & **Mask 2** & **Mask 3** \\ \hline \multicolumn{5}{c}{_Experimental group (EG)_} \\ \hline No noise & 1.11 (0.03) & 1.09 (0.02) & 1.10 (0.02) & 1.06 (0.02) \\ +10 dB SNR & 1.18 (0.03) & 1.56 (0.05) & 1.43 (0.04) & 1.41 (0.04) \\ +5 dB SNR & 1.81 (0.06) & 1.89 (0.06) & 1.95 (0.07) & 1.49 (0.05) \\ 0 dB SNR & 2.25 (0.07) & 2.63 (0.08) & 2.59 (0.08) & 2.60 (0.08) \\ \hline \multicolumn{5}{c}{_Control group (CG)_} \\ \hline No noise & 1.06 (0.04) & 1.06 (0.02) & 1.13 (0.04) & 1.08 (0.04) \\ +10 dB SNR & 1.41 (0.06) & 1.60 (0.08) & 1.52 (0.05) & 1.58 (0.07) \\ +5 dB SNR & 1.60 (0.07) & 1.88 (0.08) & 1.67 (0.08) & 1.42 (0.06) \\ 0 dB SNR & 1.78 (0.09) & 1.89 (0.09) & 2.00 (0.09) & 1.91 (0.09) \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Mean values of listening difficulty scores and related standard errors in brackets. and, overall, with an increasingly competitive acoustic scenario (i.e., with lower SNRs) even listeners with TH revealed a tendency of increased difficulty in the listening task to which they were subjected. A recently published paper by [PERSON] et al. [35] underlined that the combined effect of face masks and competitive noise scenarios further hampers speech intelligibility for HoH listeners. In their study, they showed that at decreasing SNRs, i.e., from +15 dB SNR to +10 dB SNR to 0 dB SNR, speech intelligibility drops from averages of 95%, 90%, and 50%, respectively. In particular, it lowers per noise condition when a more acoustically absorbent face mask is considered.