## 3 Results
Although there were slight differences in the shimmer (%) values extracted from female and male voice signals, it can be concluded that the two programs extract almost the same values because they both extract acoustic parameters based on the cross-correlation method. The statistical analysis between young and elderly voice signals in Table 3 was performed using [PERSON]'s U-tests for non-Gaussian distributions and two-sample \(t\)-tests for independent samples. The significance level was set to \(p\) < 0.05. Young and elderly voice signals significantly differed in normalized skewness in women (\(p\) = 0.005) and normalized kurtosis in men (\(p\) = 0.011). Thus, they can be viewed as age-related parameters that differ according to gender. Since the mean of normalized skewness estimated \begin{table}
\begin{tabular}{l l l l l l} \hline \hline  & & **Men** & \multicolumn{3}{c}{**Women**} \\ \hline  & & **Young** & **Elderly** & **Young** & **Elderly** \\ \hline Fundamental & Arithmetic mean & 125.32 & 142.23 & 213.75 & 199.06 \\ frequency (Hz) & 95\% CI for the mean & 116.24–135.11 & 134.41–150.68 & 202.65–224.42 & 188.23–209.14 \\  & SD & 4.74 & 4.17 & 5.42 & 5.22 \\  & \(p\) value & 0.004 * & & 0.008 * & \\ \hline Ppd (\%) & Arithmetic median & 8.06 & 6.87 & 4.63 & 4.88 \\  & 95\% CI for the median & 7.39–8.61 & 6.58–7.64 & 4.53–5.01 & 4.60–5.24 \\  & SD & 0.32 & 0.28 & 0.17 & 0.16 \\  & \(p\) value & 0.011 * & & 0.048 * & \\ \hline Jitter (\%) & Arithmetic median & 0.34 & 0.53 & 0.31 & 0.42 \\  & 95\% CI for the median & 0.28–0.43 & 0.37–0.71 & 0.28–0.41 & 0.32–0.56 \\  & SD & 0.03 & 0.09 & 0.03 & 0.05 \\  & \(p\) value & 0.001 * & & 0.018 * & \\ \hline Shimmer (\%) & Arithmetic median & 2.17 & 3.54 & 1.91 & 2.03 \\  & 95\% CI for the median & 1.96–2.46 & 2.54–5.07 & 1.61–2.31 & 1.72–2.50 \\  & SD & 0.14 & 0.79 & 0.15 & 0.20 \\  & \(p\) value & 0.001 * & & 0.765 & \\ \hline SNR (dB) & Arithmetic mean & 23.89 & 20.05 & 24.13 & 23.42 \\  & 95\% CI for the mean & 22.31–25.33 & 18.31–21.81 & 22.76–25.40 & 22.29–24.71 \\  & SD & 0.76 & 0.91 & 0.65 & 0.62 \\  & \(p\) value & 0.001 * & & 0.233 & \\ \hline Trk & Arithmetic median & 90.00 & 146.00 & 34.00 & 65.00 \\  & 95\% CI for the median & 60.00–135.00 & 121.00–200.00 & 21.00–43.00 & 35.00–144.00 \\  & SD & 23.62 & 17.20 & 7.01 & 28.22 \\  & \(p\) value & 0.044 * & & 0 * & \\ \hline Err & Arithmetic median & 0.00 & 5.00 & 0.00 & 1.00 \\  & 95\% CI for the median & 0.00 & 0.00–0.16 & 0.00 & 0.00–6.00 \\  & SD & 0.03 & 3.93 & 0.09 & 1.65 \\  & \(p\) value & 0 * & & 0.004 * & \\ \hline \hline \end{tabular} Note: * \(p\) < 0.05.  
\end{table} 
Table 2: Means, 95% CIs for the mean and median, and SDs for all parameters analyzed with TF32. in young female voices is close to zero, the data are normally distributed. However, the values extracted from elderly male and female voices range from \(-\)0.5 to 0.5, so the data are fairly symmetrical. As the means of the normalized kurtosis are all less than 3, the dataset is considered to have a light-tailed distribution. Figure 1 shows the results obtained in Praat. The figure presents various parameters extracted from Praat in the form of box plots, which provide better visualization of young and elderly voice signals for men and women. As shown in Figure 1a, F0 tends to increase in older men, whereas it tends to significantly decrease in older women [13]. This may be attributed to a change in the posture of elderly people who bend forward, which lowers the vocal cords. Notably, the results are the same as those obtained by other authors [34; 35]. As shown in Figure 1b, jitter was significantly higher in both men and women of all ages. The jitter represents the regularity of the oscillation cycle and the perturbation of the F0 mean, and it is related to the degree of roughness. Therefore, the results can justify the use of speech sounds as clinical cues in presbyphonia. We also obtained similarly meaningful results by analyzing other parameters, such as jitter local abs, rap, and ppq5, for the same properties (Figure 1c-e).