This isn't an issue of data, it's an issue of racist drivel being presented as medical science, people in this thread have already presented the actual data for your "questions" and surprise! Yes medical professionals are trained to expect black people to lie about pain because they're literally taught black people don't experience pain, THAT'S THE REAL WORLD DATA
See we're dealing with the dire reality of racism in the medical field and you think it's simply an issue of not having data, one: we already have the data, two: racists don't give a fuck about data, that's why the black category can only be read as "they're lying" because the rest of the categories are filled with indefensible bigotry and cartoonish caricatures, that reveals the mindset of the editor and author of the section, as such they cannot be treated as any sort of reliable transmitter of inferred data, especially when the real data contradicts their racist assertions