The results of the present systematic review showed that very few controlled clinical trials of chiropractic treatments for gastrointestinal problems have been published. The two included studies were both of very poor methodological quality; one (7
) scored 1, and the second (8
) scored zero points on the Jadad scale.
The study by Hains et al (7
) failed to control for nonspecific effects including natural history of the disease, regression toward the mean and placebo effects. Thus, the seemingly positive results may have been entirely unrelated to the interventions. Moreover, essential details regarding the patient population were missing. The authors’ conclusions do not seem justified – both treatments may have been similarly ineffective.
The pilot study by Pikalov and Kharin (8
) was not randomized. Its sample size was very small and there was no attempt to control for nonspecific effects. Moreover, unclear and subjective criteria for evaluating the clinical outcome were used, and essential patient details were not provided. The authors were aware of some of these limitations and drew adequately cautious conclusions.
Chiropractors adjust ‘subluxtions’ (ie, minimal perceived malalignments of the vertebrae). Such abnormalities – if they exisit at all – have no proven pathophysiological significance (9
). The dictum of DD Palmer (10
), the founder of chiropractic, that “95% of all diseases are caused by displaced vertebrae, the remainder by luxations of other joints” is clearly not correct. Yet many chiropractors still seem to adhere to it, arguing that “it seems unreasonable to limit the horizons of clinical chiropractic unnecessarily…” (11
Given the paucity and the poor quality of the existing evidence, this attitude seems questionable, particularly because some chiropractic treatments are associated with considerable risks (2
). Therapeutic claims should be supported by sound evidence in all areas of health care. The notion that chiropractic is an effective treatment for gastrointestinal problems is not supported by good evidence.
Unsubstantiated therapeutic claims made by chiropractors are not confined to gastroenterology. Many investigations have disclosed claims that are not based on good evidence (12
). It is, therefore – high time, one might argue – that the chiropractic profession worldwide draws the correct conclusions from this evidence and adheres to the basic principles of evidence-based medicine and medical ethics.