Support of “A Fall From the Summit” by Goertz et al.

To the EditorIn September 2019, I had the honor to attend the Global Summit event. As a participant, I was one of the primary reviewers for an included article1Balon J Aker PD Crowther ER et al.A comparison of active and simulated chiropractic manipulation as adjunctive treatment for childhood asthma. and a co-author of another included article.2Goertz CM Salsbury SA Vining RD et al.Effect of spinal manipulation of upper cervical vertebrae on blood pressure: results of a pilot sham-controlled trial. When the Summit event concluded, I had a solid understanding of the review results and that the implications would highlight the lack of evidence for spinal manipulation therapy (SMT) of the nonmusculoskeletal disorders explored and the need for further research. However, I was disappointed when the completed statement had a focus on overreaching policy implications for all nonmusculoskeletal conditions and little input or suggested changes could be made by the authors. The article by Goertz et al3

Goertz CM, Hurwitz E, Murphy B, Coulter I. Extrapolating beyond the data in a systematic review of spinal manipulation for nonmusculoskeletal disorders: a fall from the summit [e-pub ahead of print]. J Manipulative Physiol Ther. doi: https://doi.org/10.1016/j.jmpt.2021.02.003. Accessed April 17, 2021.

points out the dangers in making policy implications from finite findings arising from a review with stringent eligibility criteria. Although strict criteria are acceptable for a systematic review of efficacy and effectiveness,4Why certain systematic reviews reach uncertain conclusions. the implications and conclusions must follow equally stringent criteria.I would like to offer additional concerns that should be considered. The Summit statement lacked acknowledgment that varied intervention and control procedures could have on study findings. Although SMT was the intervention for each of these studies, SMT includes a vast array of techniques with modifiable characteristics (eg, application to different spinal areas with variable velocity and amplitudes). Although researchers continue to investigate the mechanisms of SMT, these characteristics can be modified, which is thought to explain the variety of outcomes from SMT.5Funabashi M Nougarou F Descarreaux M et al.Spinal tissue loading created by different methods of spinal manipulative therapy application. The Summit failed to acknowledge the impact that these differences may have had on individual study results. Clearly, further research is needed on these varied techniques before policy recommendations can be considered.For the control groups in the 6 selected studies, none of the shams were validated for use within the study's conditions. None were assessed for possible treatment effect on the underlying condition nor confirmed that blinding could be maintained. Although this is a well-known limitation of SMT studies,6Spinal manipulation: a systematic review of sham-controlled, double-blind, randomized clinical trials. this lack of validation could contribute to the no difference being found between groups. This methodological flaw should be addressed and further research considered before pronouncing overarching policy recommendations.To add to these concerns, the Summit cited a commentary by its own authors to highlight proposed methodological flaws for a review with opposing conclusions (ie, more research needed), yet failed to cite the follow-up response by authors of the original study that addressed these methodological flaws.7Pohlman KA Anderson K Carleo B et al.Response to ‘Methodological flaws on “manual therapy for the pediatric population: a systematic review” by Prevost et al. (2019)’. For the Summit to leave out known information in favor of only including that which fits a predetermined narrative is concerning. Although all articles carry bias of one kind or another, stakeholders should be skeptical of such bias when conclusions have such bold policy recommendations.The real conclusion should be as suggested by Goertz et al.3

Goertz CM, Hurwitz E, Murphy B, Coulter I. Extrapolating beyond the data in a systematic review of spinal manipulation for nonmusculoskeletal disorders: a fall from the summit [e-pub ahead of print]. J Manipulative Physiol Ther. doi: https://doi.org/10.1016/j.jmpt.2021.02.003. Accessed April 17, 2021.

I am hopeful that future Summit events can conduct and adopt more rigorous methodology to develop evidence-based implications and conclusions.ReferencesBalon J Aker PD Crowther ER et al.

A comparison of active and simulated chiropractic manipulation as adjunctive treatment for childhood asthma.

N Engl J Med. 339: 1013-1020Goertz CM Salsbury SA Vining RD et al.

Effect of spinal manipulation of upper cervical vertebrae on blood pressure: results of a pilot sham-controlled trial.

J Manipulative Physiol Ther. 39: 369-380

Goertz CM, Hurwitz E, Murphy B, Coulter I. Extrapolating beyond the data in a systematic review of spinal manipulation for nonmusculoskeletal disorders: a fall from the summit [e-pub ahead of print]. J Manipulative Physiol Ther. doi: https://doi.org/10.1016/j.jmpt.2021.02.003. Accessed April 17, 2021.

Why certain systematic reviews reach uncertain conclusions.

BMJ. 326: 756-758Funabashi M Nougarou F Descarreaux M et al.

Spinal tissue loading created by different methods of spinal manipulative therapy application.

Spine (Phila Pa 1976). 42: 635-643

Spinal manipulation: a systematic review of sham-controlled, double-blind, randomized clinical trials.

J Pain Symptom Manag. 22: 879-889Pohlman KA Anderson K Carleo B et al.

Response to ‘Methodological flaws on “manual therapy for the pediatric population: a systematic review” by Prevost et al. (2019)’.

BMC Complement Med Ther. 21: 5Article InfoPublication History

Published online: June 15, 2021

Accepted: April 19, 2021

Received: April 19, 2021

Publication stageIn Press Corrected ProofIdentification