# Acoustic, Myoelectric, and Aerodynamic Parameters of
## 4 Discussion  
The multifactorial analysis of the voice, both objectively and subjectively, is of great interest for the study and evaluation of vocal disorders from a global perspective. In studies where the sample was divided into two groups, only 10 specified the type of vocal pathology [12; 13; 16; 17; 18; 20; 24; 25; 26; 28]. In addition, none of the studies specified how the calculation of the sample size or the sampling procedure was performed. Both the distribution by groups (gender and number) and the age ranges observed in the included studies were quite heterogeneous, except in two of the included works [24; 25], where the same number of participants appeared in both groups. This heterogeneity may hinder the interpretation of the studies' results since both age and gender could act as factors influencing voice quality and its characteristics. Other factors such as ethno-cultural features or traits could also present a certain specificity in terms of the characteristics of the voice, as suggested by [PERSON] et al. [31]. \begin{table}
\begin{tabular}{l c c c c c c c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Author**} & \multicolumn{13}{c}{**STROBE Checklist Items for Study Title, Abstract, Introduction and Methodology**} \\ \cline{2-13}  & **1a** & **1b** & **2** & **3** & **4** & **5** & **6a** & **6b** & **7** & **8** & **9** & **10** & **11** & **12a** & **12b** & **12c** & **12d** & **12e** \\ \hline [PERSON] et al., 2010 & N & Y & Y & Y & Y & N & N & - & Y & Y & N & N & Y & Y & N & - & N \\ [PERSON] et al., 2015 & N & Y & Y & Y & Y & N & Y & - & Y & Y & Y & N & Y & Y & Y & N & - & N \\ [PERSON] \& [PERSON] et al., 2016 & N & Y & Y & Y & Y & N & N & - & Y & Y & Y & N & Y & Y & Y & N & - & N \\ [PERSON] et al., 2019 & Y & Y & Y & Y & N & Y & - & Y & Y & Y & N & Y & Y & Y & N & - & N \\ [PERSON] et al., 2018 & Y & Y & Y & Y & Y & N & Y & - & Y & Y & Y & N & Y & Y & Y & N & - & N \\ [PERSON] et al., 2011 & Y & Y & Y & Y & Y & N & Y & - & Y & Y & Y & N & Y & Y & Y & N & - & N \\ [PERSON] et al., 2001 & Y & Y & Y & Y & Y & N & Y & - & Y & Y & N & Y & Y & Y & N & - & N \\ [PERSON] et al., 2017 & Y & Y & Y & Y & Y & Y & Y & - & Y & Y & N & N & Y & Y & Y & N & - & N \\ [PERSON] et al., 2017 & N & Y & Y & N & Y & N & Y & - & Y & Y & Y & N & Y & Y & Y & N & - & Y \\ [PERSON] \& [PERSON] et al., 2006 & N & Y & Y & Y & Y & N & Y & - & Y & Y & Y & N & Y & Y & Y & N & - & N \\ [PERSON] et al., 2006 & N & Y & Y & Y & Y & N & Y & - & Y & Y & N & Y & Y & Y & Y & N & - & N \\ [PERSON] et al., 2011 & N & Y & Y & Y & Y & N & Y & - & Y & Y & N & Y & Y & Y & N & - & N \\ [PERSON] et al., 2018 & Y & Y & Y & Y & Y & N & Y & - & Y & Y & N & Y & N & Y & N & N & - & N \\ [PERSON] et al., 2014 & Y & Y & Y & Y & Y & N & Y & - & Y & Y & N & Y & Y & Y & N & - & N \\ [PERSON] et al., 2004 & N & Y & Y & Y & Y & N & Y & - & Y & Y & N & N & Y & Y & Y & N & - & N \\ [PERSON] et al., 2012 & N & Y & Y & Y & Y & N & Y & - & Y & Y & N & N & Y & Y & Y & N & - & N \\ \hline \hline \end{tabular}  
Y: reported (yes), N: not reported (no), \(\cdot\): non-applicable.  
\end{table} 
Table 6: Quality assessment for observational studies: title, abstract, introduction and methodology.