This Week In Wellness peoples self assessments of their own bodies potential to fight off a pathogen was compared with the actual levels of antibodies in their blood for that same pathogen and the results were surprisingly accurate.

https://www.sciencedaily.com/releases/2023/08/230816114132.htm

https://www.sciencedirect.com/science/article/abs/pii/S0301051123001540?via%3Dihub