[MontyCarloHall]

Not too surprising that physical differences across ethnicities are literally more than skin deep. It wouldn’t be shocking that a model could identify one’s ethnicity based on, for example, a microscope image of their hair; why should bone be any different?

I’m more surprised that the distinguishing features haven’t been obvious to trained radiographers for decades. It would be cool to see a followup to this paper that identifies salient distinguishing features. Perhaps a GAN-like model could work—given the trained classifier network, train 1) a second network to generate images that when fed to the classifier, maximize the classification for a given ethnicity, and 2) a third network to discriminate real from fake X-Ray images (to avoid generating noise that happens to minimize the classifier’s loss function). I wonder if the generator would yield images with exaggerated features specific to a given ethnicity, or whether it would yield realistic but uninterpretable images.

[eklitzke]

I think it's more likely the case that (a) most radiographers aren't trained in medical school to look for distinguishing racial features (why would they be?) and (b) in most cases the radiologist knows or can easily guess the race of the patient anyway so there's no need to try to guess it from X-ray imaging data. There are a lot of anatomical features related to race that have been known since before radiology has been a field, it's just not pertinent to the job of most radiologists.