I'll take your question seriously. Why do people do studies like this when the answer seems obvious? (1) It quantifies the seriousness of the problem. Does it

I'll take your question seriously. Why do people do studies like this when the answer seems obvious? (1) It quantifies the seriousness of the problem. Does it increase the chance of death or significant injury by 1%, 10%, 50%? Without reading the article, what is the "obvious" answer to that question? (2) People believe many "obvious" things that aren't true. They are trivial to find simply by finding two groups with opposite beliefs on a subject and both think their conclusions are obvious. Eg, did the COVID-19 vaccines reduce or increase death rates? It seems obvious to me that it was a great benefit, but there are people going on TV claiming the vaccines killed millions of people. (3) Even in areas that aren't contentious, there are many widely believed but untested assumptions. If someone didn't spend the time and effort to validate those things, we might never find what is really true. 50 years ago it was unquestioned that stress is what causes ulcers. Almost nobody questioned that except for the one guy who did the experiment that proved it was bacterial in origin. Had his result been negative, you'd be here to mock him.