Who chooses PT care over MD or DC for LBP/NP?

Finally, I've almost made it through what has become a crazy month here at UWO.  In a mistake I won't make again, I clearly bit off more than I should have by agreeing to supervise 22 students in 5 different research projects this year, and booking myself almost solid for the upcoming Canadian Physiotherapy Association's annual congress in Whistler BC.  Despite being busy howerver, the experiences I've had in supervising the research projects were very good, and some neat things have come out of them, which I'll share in a future post.  As long as I make it through CPA congress this week, I'm looking forward to catching up with things I've let slide come the second half of July.  One of those things is this blog and some much needed time to read some research.

To that end, I did spend a few minutes over my cup of Joe this morning to read a new paper in JOSPT entitled "Factors Associated with Care Seeking from Physicians, Physical Therapists, or Chiropractors by persons with spinal pain: a population-based study" by Julia Chevan and Dan Riddle from Massachusettes and Virginia, respectively.  This was a secondary analysis of survey data from the Medical Expenditure Panel Survey conducted in 2001 through 2003 (two panels, each encompassing 1 year) of US citizens.  Using a variety of statistical techniques for longitudinal survey data, the authors were able to construct two models, one evaluating factors that promoted the use of PT care of MD care alone for neck or low back pain, the other for evaluating factors that promoted PT care over chiropractic (DC) care.

Of note for the first model was that, in the sample studied, the PT care almost exclusively occurred secondary to a referral from a physician (in 203 of 233 cases).  In most cases in the US, the physicians act as a sort of gatekeeper to PT care, driven largely by health insurance requirements.  As a result however, these results may not be generalizable to countries in which PTs enjoy more direct access/primary care privileges.  The final model, which evalauted factors categorized as either predisposing (ie. demographics), enabling (ie. income, insurance coverage) and needs (ie. characteristics of the health condition itself), found the following factors (with odds ratios) are associated with seeking PT care above MD care alone:

Female sex (OR 1.65), higher income (OR 2.09), high school (OR 2.1) or college (OR 2.01) degree over those without either.

The model explaining PT care seeking over DC care for people with spinal pain retained the following factors:

Female sex (OR 2.02), lower rating of self-health (OR 1.93), and having at least 1 disability day over the previous year (OR 3.80).

So how to interpret these findings?  With the caveat of questionable generalizability outside the US that I mentioned above, it appears as though females are 65%-100% more likely to seek PT care over either MD alone or DC care for spinal pain.  Education level seems to be associated with seeking more care the MD alone, but doesn't impact the choice of PT or DC.  People who are generally less well (lower self-ratings of health and at least 1 disability day for their condition) are more likely to seek PT care than DC care.  Interestingly, whether the condition was affecting the low back or neck didn't appear to have any bearing on people's care seeking behaviours in any comparison.

Overall this appears to have been a well-done study.  Survey research can be difficult to interpret at times, and even in a large study like this one (over 2300 cases of care) the results are not cut and dry.  While the data came from two years of survey research, it was not prospective in nature (each year respondents were asked about cases that occurred in the previous year), which renders cause and effect impossible to draw.  If I were to speculate on a mechanism, and this is purely speculation, it looks to me as though the sample surveyed might view DC as requiring somewhat greater intestinal fortitude than PT - in other words it's more of a treatment choice for the 'tough and manly' who can handle the risk and the slight discomfort, whereas PT may be viewed as a somewhat gentler approach more geared towards people with greater health problems.  What do you think?  Do you have a different interpretation?  Feel free to share in the comments section below.