I came across this article courtesy of a colleague down under. While there is a lot of modern/current published research on chiropractic applications to more straightforward neuromusculoskeletal conditions, the first chiropractors were much more interested in chiropractic impact on the the general health and well being of their patients by affecting the spine-central nervous system connection.
In that regard, this piece of research would be more in line with “early chiropractic”. The SF36 is a broadly recognized tool to assess a person’s overall well being rather than condition specific wellness. The first aspect of the research is that spinal and neuromusculoskeletal conditions are associated with a higher reported state of decreased well being that one might expect. The second aspect is that chiropractic intervention seems to improve the SF36 and thus the state of well being independently of the concurrent decrease in pain, which seems to indicate that chiropractic care affects well being not just by decreasing pain, as has been previously reported, but also by simply normalizing input to parts of the brain involved in mood regulations. This is very much what I have observed in over 2 decades of clinical practice, when proactive patients will often return for care with a sense that “something is off”, a sensation of not feeling well that they have recognized to precede the arrival of pain symptoms by a few weeks.