The most recent issue of the Journal of Manipulative and Physiological Therapeutics has a series of 3 papers that will help to fill the evidence gap and answer the question "Does inclusion of chiropractic care result in cost savings?" Each of these papers focuses on one area of musculoskeletal health that has been identified as a public health burden: low back pain, neck pain, and headache.  Check out each one at the following links:

http://www.jmptonline.org/article/S0161-4754(16)00055-5/abstract

http://www.jmptonline.org/article/S0161-4754(16)00053-1/abstract

http://www.jmptonline.org/article/S0161-4754(16)00054-3/abstract