There are scores of studies from around the world showing the effectiveness of chiropractic manipulation. Here are excerpts from just a few of those studies:

For Acute Low-Back Pain:

"For patients with acute low-back symptoms without radiculopathy (ed.sciatica), the scientific evidence suggests spinal manipulation is effective in reducing pain and perhaps speeding recovery within the first month of symptoms." - Clinical Practice Guidelines, AHCPR (1994)

For Long-Term (Chronic) Low-Back Pain:

"There is strong evidence that manipulation is more effective than a placebo treatment for chronic low-back pain or than usual care by the general practitioner, bed rest, analgesics and massage." - Spine, Van Tulder and Bouter et al. (1997)

"...improvement in all patients at three years was about 29% more in those treated by chiropractors than in those treated by the hospitals. The beneficial effect of chiropractic on pain was particularly clear." - British Medical Journal, Meade et al. (1995)

"Manipulative therapy and physiotherapy are better than general practitioner and placebo treatment. Furthermore, manipulative therapy is slightly better than physiotherapy after 12 months." - British Medical Journal, Koes et al. (1992)

Neck and Back Pain:

"...patients suffering from back and/or neck complaints experience chiropractic care as an effective means of resolving or ameliorating pain and functional impairments, thus reinforcing previous results showing the benefits of chiropractic treatment for back and neck pain." - Journal of Manipulative and Physiological Therapeutics, Verhoef et al. (1997)

"...for the management of low-back pain, chiropractic care is the most effective treatment, and it should be fully integrated into the government's health care system." - The Manga Report (1993)

Headaches:

"Cervical spine manipulation was associated with significant improvement in headache outcomes in trials involving patients with neck pain and/or neck dysfunction and headache." - Duke Evidence Report, McCrory, Penzlen, Hasselblad, Gray (2001)

"The results of this study show that spinal manipulative therapy is an effective treatment for tension headaches. . . Four weeks after cessation of treatment . . . the patients who received spinal manipulative therapy experienced a sustained therapeutic benefit in all major outcomes in contrast to the patients that received amitriptyline therapy, who reverted to baseline values." - Journal of Manipulative and Physiological Therapeutics, Boline et al. (1995)

Cost Effectiveness:

A 4-year retrospective review of claims from 1.7 million health plan members analyzed the cost effects of having a chiropractic benefit in their HMO insurance plan. The data revealed that members with the chiropractic benefit had lower overall total annual health care costs. Back pain patients with chiropractic coverage also realized lower utilization of plain radiographs, low back surgery, hospitalizations and MRI's. Back pain episode-related costs were also 25 percent lower for those with chiropractic coverage ($289 vs. $399). - Archives of Internal Medicine (2004)

This study compared the benefits of spinal manipulation and exercise to “best care” in general practice for patients consulting for back pain. 1,287 patients were recruited, divided into treatment groups and followed for more than one year. Patients receiving manipulation and exercise had lower relative treatment costs and received more treatment benefits than those treated with general medical care. The authors believe that this study was able to show convincingly that manipulation alone and manipulation followed by exercise provided cost-effective additions to general practice. - British Medical Journal (2003)