Original sentence: In contrast, the Canadian Chiropractic Association supports vaccination  as a cost-effective and clinically efficient public health preventative procedure for certain viral and microbial diseases.The holistic philosophy of chiropractic suggests that disease prevention should occur by strengthening the host from within, yet there is strong evidence to support the use of vaccinations in the prevention of certain diseases.There are differences of opinion within the chiropractic profession regarding interventions for the prevention of some types of disease.This disparity is exhibited even in statements within national associations, for example the American Chiropractic Association and the International Chiropractic Association support exemptions to compulsory vaccination laws on the grounds that, since vaccines have risk, patients should be allowed the freedom to choose.This has caused significant disparity among chiropractors as they struggle to find their niche in the healthcare arena
Edited sentence: Although vaccination is one of the most cost-effective forms of prevention against infectious disease, traditional chiropractic philosophy is that diseases are traceable to causes in the spine and that vaccines therefore have no benefits to outweigh their risks, and most chiropractic writings on vaccination focus on its negative aspects.Some disease prevention methods are controversial within chiropractic.Surveys in Canada in 2000 and 2002 found that about 40% of chiropractors supported vaccination, and that over a quarter opposed it and advised patients against vaccinating themselves or their children.The Canadian Chiropractic Association supports vaccination, but the American Chiropractic Association and International Chiropractic Association cite vaccine risk and support exemptions to compulsory vaccination laws