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bibliography * The PainScience Bibliography contains plain language summaries of thousands of scientific papers and others sources, like a specialized blog. This page is about a single scientific paper in the bibliography, Williams 2011.

How much of treatment effect is needed to actually matter?

Williams NH. How important is the ‘minimal clinically important change’? International Musculoskeletal Medicine. 2011 Jun;33(2):47–82(2).
Tags: scientific medicine, spinal adjustment, spine, treatment

PainSci summary of Williams 2011?This page is one of thousands in the bibliography. It is not a general article: it is focused 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. ★★★☆☆?3-star ratings are for typical studies with no more (or less) than the usual common problems. 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.

There are various ways of measuring improvement in scientific tests of treatments. As this paper points out, “when an outcome measure improves by, say, five points it is not immediately apparent what this means.” How much improvement matters? It is extremely common for experimenters to confirm real, statistically significant treatment effects that are nevertheless trivial. This paper discusses how much benefit is needed to be taken seriously, and cites the damning example of spinal manipulation. Chiropractors routinely claim that the benefits of spinal adjustment are “proven,” but the authors point out that trials have “shown an effect size for manipulation that is less than the threshold for what is clinically worthwhile.”

I think it’s particularly noteworthy that these authors have no particular axe to grind about chiropractic treatment — this is not a paper about that. They simply needed a good example to make their point, and it’s telling that they picked spinal manipulative therapy.

original abstract

Patient-based outcome measures have been developed to measure the health status of patients suffering from many conditions found in musculoskeletal medicine. Many types have been developed. Generic measures can be used across a broad spectrum of illness and can compare the health of an affected group with that in the general population.1 Condition-specific instruments on the other hand measure the effect of a single condition on health. Compared to generic measures they have a narrower focus and are more sensitive to small but clinically significant changes in health status over short periods. Examples include the Roland–Morris questionnaire2 for low back pain and Western Ontario McMaster universities arthritis index (WOMAC) for osteoarthritis.

related content

These two articles on cite Williams 2011 as a source:

This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog.