4 collisions with deer in 5 years prior to using the whistles

by DR
(TEXAS)

From 1990 -1995 - I had a truck totaled from collision with deer, another hit cost me $1000 and others that left radiator needing repair and left dents on my front end.

Since then, I have used dozens of whistles on dozens of vehicles and NEVER had another collision, though I travel the same roads and have not changed any other behaviors than use these devices.
I am PhD.
I know how to do research...these are case studies that provide valid and reliable evidence.
Dr. M.