Previously I discussed why I think bubbles occur in the US but I left out why I took the position I did, and I was asked so the answer is:
I asked the market. Starting from the assumptions that I layed out the conclusion is fairly straightforward. The bubble sector* would be one that has grown much faster than the surrounding economy and then showed strong signs of a peak just as the yield curve started to invert. There were a few other check marks that it would need to have, such as increased demand or government meddling recently to explain why they were the sector that the money flowed into, but those were obvious for healthcare once I found that the other two patterns fit.
As for individual companies I went through and chose one whose growth appeared to have benefited the most from this situation (stock price wise).
*There doesn't have to be just one.