What makes you think that conductor paid more? Certainly nothing that I said! Likewise what makes you think that the epidemiology was hard? The statistics were

What makes you think that conductor paid more? Certainly nothing that I said! Likewise what makes you think that the epidemiology was hard? The statistics were absolutely brutally obvious. The main problem was getting people to look at the data, not interpreting it. See https://bcmj.org/articles/exercise-and-heart-review-early-studies-memory-dr-rs-paffenbarger https://bcmj.org/articles/exercise-and-heart-review-early-st... for some of the early history that is involved here.