I've never seen research about this. It would be hard to fund/publish because the results would shock people and be highly controversial.
But imagine if we could follow a large cohort, and carefully track their symptoms and what conditions those symptoms are attributed to over time. Perhaps giving them workups from doctors critical of psychosomatic medicine. The numbers could be scary. Like what if 5% of people in the general population experience, at some point, a medical condition that's initially diagnosed as mental or minor.