National associations of chiropractors from these countries are members of a World Federation of Chiropractic, based in Toronto, Canada, which is in official relations with the World Health Organization. In North America there is a minimum of six years full time university-level education, which includes two years of university credits in qualifying subjects and then a four year undergraduate program at chiropractic college. Postgraduate specialties include chiropractic sciences, neurology, nutrition, orthopedics, radiology, rehabilitation and sports chiropractic. In most countries these colleges are now in the public university system. The practice of chiropractic is now recognized and regulated by law in many countries in all world regions.
Diagnosis includes the right to use x-ray and other diagnostic imaging and tests.
The professional titles most commonly approved by law in the U.S. states and Canadian provinces are chiropractor and doctor of chiropractic . Many U.S. states also approve the title chiropractic physician . In these states the title physician is given to chiropractic, medical and osteopathic doctors in recognition of their competence and duty to perform a diagnosis. Patients requiring these interventions are referred for medical care. Chiropractors use natural or non-invasive treatment approaches including manual treatments, physical therapy modalities, exercise programs, nutritional advice, orthotics, lifestyle modification and other patient education.