Association does not equal causation

Here is a response I wrote to an article reprinted in the Arlington Heights newspaper. 
"This is a reprint of an article from the Washington Post that I had previously read. As in all of medicine, it is very difficult to study rare events such as vertebral artery dissections. Several of the early studies on this topic were just surveys of neurologists. The 2008 Cassidy study of millions of medical records in Ontario, Canada showed that the incidence of this event is the same after chiropractic treatment as after treatment by a family physician ( about 5 times more likely), lending much credence to the theory that these dissections had already occurred and were causing symptoms such as neck pain and/ or headache which then brought the patient to the practitioner. This injury has also been associated with 40 everyday activities such as hair washing with neck extended such as in hair parlors, surgical intubation, and star gazing, and can occur insidiously (for no apparent reason)."

https://www.dailyherald.com/article/20140120/entlife/701209979/