The greatest hits of back pain science are a disappointment
PainSci summary of Machado 2009?This page is one of thousands in the PainScience.com bibliography. It is not a general article: it is focussed on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided at the bottom of the page, as often as possible. ★★★★★?5-star ratings are for sentinel studies, excellent experiments with meaningful results. Ratings are a highly subjective opinion, and subject to revision at any time. If you think this paper has been incorrectly rated, please let me know.
This is a meticulous, sensible, and readable analysis of the very best studies of back pain treatments that have ever been done: the greatest hits of back pain science. There is a great deal of back pain science to review, but authors Machado, Kamper, Herbert, Maher and McCauley found that shockingly little of it was worth their while: just 34 acceptable studies out of a 1031 candidates, and even among those “trial quality was highly variable.” Their conclusions are derived from only the best sort of scientific experiments: not just the gold-standard of randomized and placebo-controlled tests, but carefully choosing only the “right” kind of placebos (several kinds of placebos were grounds for disqualification, because of their known potential to skew the results). They do a good job of explaining exactly how and why they picked the studies they did, and pre-emptively defending it from a couple common concerns. The results were sad and predictable, robust evidence of absence: “The average effects of treatments … are not much greater those of placebos.”
OBJECTIVE: Estimates of treatment effects reported in placebo-controlled randomized trials are less subject to bias than those estimates provided by other study designs. The objective of this meta-analysis was to estimate the analgesic effects of treatments for non-specific low back pain reported in placebo-controlled randomized trials.
METHODS: Medline, Embase, Cinahl, PsychInfo and Cochrane Central Register of Controlled Trials databases were searched for eligible trials from earliest records to November 2006. Continuous pain outcomes were converted to a common 0-100 scale and pooled using a random effects model.
RESULTS: A total of 76 trials reporting on 34 treatments were included. Fifty percent of the investigated treatments had statistically significant effects, but for most the effects were small or moderate: 47% had point estimates of effects of <10 points on the 100-point scale, 38% had point estimates from 10 to 20 points and 15% had point estimates of>20 points. Treatments reported to have large effects >20 points) had been investigated only in a single trial.
CONCLUSIONS: This meta-analysis revealed that the analgesic effects of many treatments for non-specific low back pain are small and that they do not differ in populations with acute or chronic symptoms.
- “Systematic review of manual therapies for nonspecific neck pain,” an article in Joint Bone Spine, 2013.
- “More questions than answers,” an article in Physical Therapy, 2002.
These five articles on PainScience.com cite Machado 2009 as a source:
- PS Save Yourself from Low Back Pain! — Low back pain myths debunked and all your treatment options reviewed
- PS Microbreaking — Lots of little breaks may compensate
- PS Healer Syndrome — The problem with health care professionals, especially in alternative medicine, who want to be known as “healers”
- PS Does Spinal Manipulation Work? — Spinal manipulation, adjustment, and popping of the spinal joints and the subluxation theory of disease, back pain and neck pain
- PS Pseudo-quackery in Chronic Pain Care — A field with a large gray zone between overt quackery and evidence-based care for chronic pain and injury rehabilitation