On the one hand, it could be rational if based on observational or social learning.
These estimates were based on observational data during infant observation.
I won't repeat the tale here, but colleagues and I discovered that what we thought we knew about hormone replacement at menopause based on observational trials was a bit wrong in one direction, while what we thought we learned from subsequent RCTs was at least as wrong in a different direction.
As we observed here, most studies are based on observational research.
The initial promises made that HRT could reduce future cardiovascular disease were based on observational studies.
For example, Dr. Berry notes that, based on observational studies, thousands of women were given bone marrow transplants for breast cancer.
This was based on observational studies in Africa, which noted that people there had diets high in fiber and correspondingly low rates of colon cancer.
To date, the published data are predominantly based on observational trials and small case series [8].
Therefore, this article proposes an explanatory hazard mapping approach based on observational design.
Sober gives a related but stronger argument based on observational selection effects (Sober 2009, 77 80).
