Chiropractic evidence under attack in BCA/Singh case
Previously I wrote about the British Chiropractic Association suing science writer Simon Singh for libel. This has been widely criticized as a tactical mistake due both to the expense and to the negative publicity which has thus far ensued. The BCA has recently produced a list of evidence justifying the chiropractic treatment of children with asthma and colic which evidence-based blogs have proceeded to, for want of a better term, eviscerate. One of the criticisms was for the BCA not including a study which showed manipulation to be no better than placebo for infantile colic.
Other criticisms of some of the studies from the Ministry of Truth
Klougart et al. is an uncontrolled prospective study that provided the first [alleged] evidence for the use of chiropractic manipulation in treating infantile colic. Although noteworthy for its size – 316 infants were recruited to the study – it lacks blinding, randomisation and a control group and is, therefore, subject to a considerable degree of bias and offers no means of assessing its findings against either a placebo or simply allowing the condition to run it natural course, colic being a condition that typically improves over time.
The BCA’s inclusion of the paper by Mercer and Nook, which claims a 93% success rate in actually curing colic, in its list of evidence is nothing short of a complete embarrassment. No information given on dropouts RCT (level 1b). Single blinded study. Randomisation unclear. Subjective response to treatment by parents before treatment and at each subsequent consultation. Outcomes not defined. Statistically significant difference (no data given) in response to treatment between 2 groups (assumed beneficial in experimental group). Complete resolution of symptoms in 93% of infants in (assumed) experimental group. No comparative data for placebo group.
The third study, Wiberg et al. is perhaps the best designed of the three but still not without significant flaws. It is a single blinded study of 50 infants, 25 of whom were given chiropractic treatment while 25 were treated with dimethicone, a common, over the counter, colic remedy which has been shown to perform no better than a placebo. Nine of the 25 infants treated with dimethicone dropped out of the study with their parents citing a worsening of symptoms, rather than a medication bias. The big problem with this study is that the parents were fully aware of which treatment their child was receiving and the researchers failed to conduct an ‘intention to treat’ analysis prior to beginning the study, the upshot of which being that the outcomes reported are prone to a significant degree of parental bias.
Most blogs that I’ve read come down squarely on Singh’s side. A typical example might lament that a “powerful organization” like the BCA is using it’s legal muscle to silence one lonely voice. Some other thoughts from online articles:
“The association could have challenged the author in an open debate, providing the evidence Mr. Singh said did not exist. Instead, it sued the author for libel. In a remarkable ruling last month, Justice David Eady decided that Mr. Singh’s article was defamatory because, according to the judge, Mr. Singh implied that the association deliberately misled the public.
Mr. Singh, though, didn’t suggest that the chiropractors were being dishonest — after all, they might sincerely believe that their treatment is effective. He simply questioned the scientific validity of their claims.”
The British Medical Journal writes:
“The fundamental point is that it is essential in the scientific sphere, and in particular in the world of medicine, for claims of efficacy to be subject to the most stringent examination and criticism. In the field of health care, the consumer is particularly vulnerable to false promises of cure or symptomatic relief, and all practitioners—especially those in the private sector—need to be able to justify their claims in a transparent and scientific way. If that debate is chilled, then the medical profession, patients’ interests, and scientific discourse are severely undermined.”
It’s hard to argue with that sentiment however, apparently there are some who feel we have sufficient evidence to justify the treatment of colic in kids. A British Medical Journal publication The Archives of Disease in Childhood states:
“In this clinical scenario (colic) where the family is under significant strain, where the infant may be at risk of harm and possible long term repercussions, where there are limited alternative effective interventions, and where the mother has confidence in a chiropractor from other experiences, the advice is to seek chiropractic treatment.”
A reasonable discussion on the evidence for chiropractic treatment of paediatric asthma is to be found on the Evidence Matters blog.
So, how much evidence is enough? Clinical decision-making in the office should rely on best evidence whenever possible. The best approaches are found in national association produced clinical guidelines if available and these should be kept up-to-date when better information becomes available.
The upshot of this mess is if more chiropractors based their scope of practice on good evidence rather than obvious marketing strategies this whole event might have been avoided. As it is, maybe there is something that can be learned. The outlandish claims and dogmatic beliefs of too many of us will continue to foster a sense of paranoia where we feel the need to quash ANY perceived threat by legal action rather than improve communication and understanding through informed debate. In the meantime there will be suspicions that chiropractic is a second-rate profession.