## 2 Materials and Methods
### Fuzzy Cognitive Map Model  
The FCM model consists of 34 input symptoms related to the conditions of Brain Fog (BF), Attention Deficit (AD), Memory Problems (MP), Dyspnea (D), Communication Problems (CP), Swallowing (Sw), Excessive Saliva (ES), Voice Disorders (VD). The output decision Table 3 shows the FCM concepts. Depending on the Values of the output nodes one decision is made (maximum value) consultation with an ENT specialist, Pulmonologist, Neurologist, or SLP. In the event that the output node values are all less than 0.3, then the DSS gives a decision of \"Low risk\" of developing these conditions. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline  & **Brain Fog** & **Attention** & **Memory** & **Breathing** & **Communication** & **Swallowing** & **Excessive** & **Voice** \\  & **Deficit** & **Problems** & **Problems** & **Problems** & **Problems** & **Swallowing** & **Silvation** & **Disorders** \\ \hline Population* & 95,871 & 68,835 & 62,867 & 97,230 & 150 & 96,797 & 5002 & 1122 \\ \hline Weighted Average & 0.129 & 0.130 & 0.131 & 0.147 & 0.070 & 0.069 & 0.070 & 0.029 \\ \hline Weighted Maximum & 0.314 & 0.380 & 0.329 & 0.334 & 0.133 & 0.239 & 0.109 & 0.062 \\ \hline Weighted Minimum & 0.025 & 0.090 & 0.028 & 0.011 & 0.020 & 0.005 & 0.060 & 0.012 \\ \hline \hline \end{tabular}
* Total population in reported studies.  
\end{table} 
Table 2: Weighted average, maximum, and minimum prevalence of conditions across all studies. Figure 3: Nonlinear weighting function according to size of sample. The causality weights between symptoms and outputs were determined based on the weighted values of Table 2, where each symptom was related to one or more conditions and the specialty under which it fell. The resulting FCM-DSS model is shown in Figure 4.  
Figure 4: Competitive Fuzzy Cognitive Map for Post-Covid. \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & \multicolumn{4}{c}{**Concepts**} \\ \hline C1. Difficulty Functioning & C10. Feeling of Confusion & C19. Time Management & C28. Unexplained \\  & C10. Feeling of Confusion & Difficulties & Dysaesthesia in Month \\ \hline C2. Difficulty Breathing & C11. Difficulty with & C20. Impulsiveness & C29. Extended Medication \\  & Activity Execution & & During Acute Phase \\ \hline C3. Shortness of Breath & C12. Post-Covid Stress & C21. Memory Problems & C30. Affected Food \\  & C13. Mental Fatigue & Worsening Post-Covid & Consumption Post-Covid \\ \hline C4. Cough & C13. Mental Fatigue & C22. Sleep Problems & C31. Affected Sense of Taste \\ \hline Input Concepts & C5. Apnea & C14. Difficulty & C23. Word Finding Problems & C32. Weight Loss \\  & Recalling Information & & C24. Difficulty & C33. Swallowing Difficulties \\ \hline C6. Changes in Voice & C15. Difficulty Retaining & & Remembering Words & C33. Swallowing Difficulties \\  & Quality & & & \\ \hline C7. Hoarseness & C16. Difficulty Maintaining & C25. Difficulties & C34. Reduced Appetite \\  & Conversation Topic & Understanding Language & C34. Reduced Appetite \\ \hline C8. Voice Fatigue & C17. Difficulty & C26. Decreased & \\  & Maintaining Attention & & Saliva Secretion & \\ \hline C9. Increased Effort to & C18. Difficulty & & & \\ \multicolumn{1}{c}{Speak} & Organizing Activities & & \\ \hline Output Concepts & C35. Pulmonologist & C36. ENT Specialist & C37. Neurologist & C38. SLP \\ \hline \hline \end{tabular}
\end{table} 
Table 3: FCM Concepts. The implementation of the FCM-DSS was carried out in MATLAB (v.2023), which presents a series of questions for each symptom of the reported problems. The user responds to these questions based on their subjective assessment of their symptoms. For example, one of the symptoms related to voice is hoarseness, with possible responses being None, Low, Moderate, or High. These responses, along with all others, are cumulatively assessed using the FCM-DSS, which evaluates their severity based on the causal relationships between concepts.