## 2 Materials and Methods
### Weighted Symptom Prevalence  
An evaluation of selected research studies was conducted using the PICO (Population, Intervention, Comparison, Outcome) methodology ([PERSON] et al., 2010). None were given a rating of LOW, while four were assessed as MODERATE due to unclear research questions in one of the evaluation areas. Specifically, the studies ([PERSON] et al., 2018; [PERSON] et al., 2018; [PERSON] et al., 2018), were rated moderate because, in the outcomes section, the use of the questionnaires employed did not clearly target specific \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Study** & **Population** & **Brain Fog** & \begin{tabular}{c} **Attention** \\ **Deficit** \\ \end{tabular} & \begin{tabular}{c} **Memory** \\ **Problems** \\ \end{tabular} & \begin{tabular}{c} **Breathing** \\ **Problems** \\ \end{tabular} & \begin{tabular}{c} **Communication** \\ **Problem** \\ \end{tabular} & \begin{tabular}{c} **Swallowing** \\ **Sailvation** \\ \end{tabular} & \
\begin{tabular}{c} **Excessive** \\ **Disorders** \\ \end{tabular} &
\begin{tabular}{c} **Voice** \\ **Disorders** \\ \end{tabular} \\ \hline [PERSON] & & & & & & & & & \\ et al. ([PERSON] et al., 2018) & 61,002 & 0.34 & 0.27 & 0.26 & 0.05 & & 0.09 & \\ \hline [PERSON] & & & & & & & & \\ et al. ([PERSON] et al., 2018) & 96 & 0.49 & & 0.56 & 0.43 & & & \\ \hline [PERSON] & & & & & & & & \\ et al. ([PERSON] et al., 2018) & 2696 & 0.07 & & & & & & \\ \hline [PERSON] & & & & & & & & \\ et al. ([PERSON] et al., 2018) & 100 & 0.85 & 0.27 & 0.32 & 0.46 & 0.02 & & \\ \hline [PERSON] & & & & & & & & \\ et al. ([PERSON] et al., 2018) & 134 & 0.10 & 0.25 & 0.37 & 0.60 & & 0.09 & \\ \hline [PERSON] & & & & & & & & \\ et al. ([PERSON] et al., 2018) & 4861 & 0.10 & 0.14 & & 0.19 & & 0.03 & 0.06 \\ \hline [PERSON] & & & & & & & & \\ et al. ([PERSON] et al., 2018) & 1733 & & & & & & & \\ et al. ([PERSON] et al., 2018) & 213 & 0.38 & & & 0.38 & & 0.23 & \\ \hline [PERSON] & & & & & & & & \\ et al. ([PERSON] et al., 2018) & 465 & & & & & & & \\ et al. ([PERSON] et al., 2018) & 1022 & 0.08 & 0.64 & 0.55 & 0.56 & & 0.40 & 0.01 \\ \hline [PERSON] et al. ([PERSON] et al., 2018) & 316 & & & 0.10 & & & & 0.39 & 0.05 & \\ \hline [PERSON] & & & & & & & & & \\ et al. ([PERSON] et al., 2018) & 50 & 0.70 & & 0.38 & 0.66 & 0.44 & 0.46 & \\ \hline [PERSON] & & & & & & & & \\ et al. ([PERSON] et al., 2018) & 25,910 & 0.02 & & & & & & \\ \hline [PERSON] & & & & & & & & \\ et al. ([PERSON] et al., 2018) & 96 & & & & & & & \\ et al. ([PERSON] et al., 2018) & 222 & & 0.09 & 0.05 & 0.40 & & 0.03 & \\ \hline [PERSON]- & & & & & & & & \\ Corona & & & & & & & & \\ et al. ([PERSON] et al., 2018) & 141 & & & & & & & \\ et al. ([PERSON] et al., 2018) & 100 & 0.22 & 0.18 & 0.50 & & 0.08 & 0.20 \\ \hline [PERSON] & & & & & & & & & \\ et al. ([PERSON] et al., 2018) & 720 & 0.30 & & & & & & \\ et al. ([PERSON] et al., 2018) & 49 & & & & & & & \\ \hline \hline \end{tabular}  
* Population indicates the sample size of each study. The columns list the relative frequency of specific symptoms related to speech-language pathology as reported in the studies. The values represent the proportion of the study population that exhibited these symptoms.  
\end{table} 
Table 1: Speech-language pathology-related symptoms of long COVID and their relative frequency in the studies *. results. On the other hand, [47] was evaluated as moderate because, in the comparison area, it was not clear what was being compared. The remaining fifteen studies met all the criteria in the four areas of the PICO framework as set out for the purposes of this research and were characterized as studies of HIGH rating. Finally, an assessment of the prevalence of SLP-related conditions across the total population was conducted. Populations in each study exhibiting altered mental status, attention deficit, memory problems, dyspnea, communication disorders, swallowing/feeding disorders, sialorrhea, or voice disorders were recorded.