Efficacy of Chiropractic Manual Therapy on Infant Colic: A Pragmatic Single-Blind, Randomized Controlled Trial
Efficacy of Chiropractic Manual Therapy on Infant Colic:
A Pragmatic Single-Blind, Randomized Controlled Trial
J Manipulative Physiol Ther. 2012 (Oct); 35 (8): 600–607
Joyce E. Miller, BS, DC, David Newell, PhD,
Jennifer E. Bolton, PhD
Associate Professor, Anglo-European College of Chiropractic, Bournemouth, UK. firstname.lastname@example.org.
OBJECTIVE: The purpose of this study was to determine the efficacy of chiropractic manual therapy for infants with unexplained crying behavior and if there was any effect of parental reporting bias.
METHODS: Infants with unexplained persistent crying (infant colic) were recruited between October 2007 and November 2009 at a chiropractic teaching clinic in the United Kingdom. Infants younger than 8 weeks were randomized to 1 of 3 groups: (i) infant treated, parent aware; (ii) infant treated, parent unaware; and (iii) infant not treated, parent unaware. The primary outcome was a daily crying diary completed by parents over a period of 10 days. Treatments were pragmatic, individualized to examination findings, and consisted of chiropractic manual therapy of the spine. Analysis of covariance was used to investigate differences between groups.
RESULTS: One hundred four patients were randomized. In parents blinded to treatment allocation, using 2 or less hours of crying per day to determine a clinically significant improvement in crying time, the increased odds of improvement in treated infants compared with those not receiving treatment were statistically significant at day 8 (adjusted odds ratio [OR], 8.1; 95% confidence interval [CI], 1.4-45.0) and at day 10 (adjusted OR, 11.8; 95% CI, 2.1-68.3). The number needed to treat was 3. In contrast, the odds of improvement in treated infants were not significantly different in blinded compared with nonblinded parents (adjusted ORs, 0.7 [95% CI, 0.2-2.0] and 0.5 [95% CI, 0.1-1.6] at days 8 and 10, respectively).
CONCLUSIONS: In this study, chiropractic manual therapy improved crying behavior in infants with colic. The findings showed that knowledge of treatment by the parent did not appear to contribute to the observed treatment effects in this study. Thus, it is unlikely that observed treatment effect is due to bias on the part of the reporting parent.
Excessive infant crying in otherwise healthy infants, traditionally called infant colic, continues to be an enigmatic condition with no known cause and no known cure. [1-3] Afflicting between 10% to 30% of all infants and consuming significant health care resources,  infant colic is a problem for parents and clinicians, both of whom try a wide range of therapies with often disappointing results.
Despite decades of research, a clear pathogenesis has not been elucidated. Notwithstanding, what is clear is that underlying disease is rare in the excessively crying baby  and that half of those affected recover by 6 months of age,  with a small proportion at risk of injury  or long-term developmental problems. [7-9] In an effort to help their child with what appears to be a painful condition, some parents choose complementary and alternative medicine (CAM), including chiropractic manual therapy. [9-12] To date, several randomized trials have been reported, [13-19] and although these trials demonstrate some reduction in crying, weaknesses in study methodologies have compromised their contribution to the evidence base. [20-23]
A Danish study in 1999  showed manual therapy resulted in a significant reduction in crying in a 2-week trial when compared with simethicone (known to have no effect over placebo ) as a control. However, the parents were not blind to treatment allocation, which could have biased their reports of outcome. Similarly, a British study in 2006, comparing manual therapy with no treatment, showed significant declines in crying in the treatment group, but again, parents were not blind to the intervention received.  In contrast, a Norwegian study in 2002, which did blind the parents to treatment allocation, showed similar reductions in crying with manual therapy and with placebo.  However, the manual therapy in that trial was an intervention nonspecific to the patient. A British study in 2005 compared 2 manual therapies, and although participants in both treatment arms showed reductions in crying, there was no placebo group for comparison.  Finally, 3 South African studies showed that significant improvements in crying with manual therapy over detuned ultrasound  and medication [18, 19] can only be found in conference proceedings and therefore remain unpublished in the peer-reviewed literature. Based on these studies, there is some but not conclusive evidence to make a recommendation of manual therapy for the excessively crying baby.  For there to be a better understanding about the efficacy of chiropractic treatment for infants with colic, these methodological weaknesses should be addressed.
Therefore, the objectives of this study were to conduct a single-blind, randomized controlled trial comparing chiropractic manual therapy with no treatment and to determine whether parents’ knowledge of treatment biases their report of change in infant crying. The questions posed were as follows:
(i) in colicky infants, is there a difference in crying time between infants who receive chiropractic manual therapy and those who do not, and
(ii) in colicky infants, is there a difference in infant crying time between parents blinded and parents not blinded to treatment?
In conclusion, the findings of this study demonstrate a greater decline in crying behavior in colicky infants treated with chiropractic manual therapy compared with infants who were not treated. The findings also showed that knowledge of treatment by the parent did not appear to contribute to the observed treatment effects in this study. Thus, it is unlikely that observed treatment effect is due to bias on the part of the reporting parent.
- This study found that excessively crying infants were at least 5 times as likely to cry significantly less if they were treated with chiropractic manual therapy than if they were not treated, even when brought to the same venue.
- Infants who were treated were equally likely to improve, whether the parents were blinded to treatment or not.
- Parents expected a short course of treatment and left care if no improvement was seen in the first week as well as if recovery was obtained in the first week.