I believe I have found a perfect example where the "Medical Model is Wrong," and I am currently working on a post about it. However, I am swamped with other tasks, I wonder if I will ever finish it.
In my case, I am highly confident that my model is correct, while the majority of the medical community is wrong. Using your bullet points:
1.Personal: I have personally experienced this disease and know that the standard treatments do not work.
2.Anecdotal: I am aware of numerous cases where the conventional treatment has failed. In fact, I am not aware of any cases where it has been successful.
3.Research papers: I came across a research paper from 2022 that shares the same opinion as mine.
4.Academics: Working in academia, I am well aware of its limitations. In this specific case, there is a considerable amount of inertia and a lack of communication between different subfields, as accurately described in the book "Inadequate Equilibria" by EY.
5.Medical: Most doctors hold the same opinion because they are influenced by their education. Therefore, if 10 doctors provide the same response, it should not be considered as 10 independent opinions.
6.Countercultural experts: No idea here
7.Communities: I have not explored this extensively, but completing this post I am talking about might be the beginning
8. Someone claims to have completely made the condition disappear using arbitrary methods. I am not personally aware of any such cases but I suspect that it is feasible and could potentially be relatively simple.
9.Models: I have a precise mechanistic model of the disease and why the treatments fail to cure it. I work professionally in a field closely related to this disease.
In summary, my confidence comes from, 1. being an expert in a closely related field and understanding what other people are missing and above all, why they are missing it, 2. having a mechanistic model 3. finding publications that manifest similar opinions.