Functional Movement Screen unreliable

PainSci » bibliography » Whiteside et al 2014
updated Nov 22, 2024

Tags: diagnosis, etiology, exercise, debunkery, sports, bad science, fibromyalgia, pro, self-treatment, treatment, research, scientific medicine, contested illness, pain problems, controversial, medically unexplained symptoms, signs & symptoms, pain

Four pages on PainSci cite Whiteside 2014: 1. The Complete Guide to IT Band Syndrome 2. Is Diagnosis for Pain Problems Reliable? 3. The Functional Movement Screen (FMS) Reviewed 4. FMS: Back to the drawing board?

PainSci commentary on Whiteside 2014: ?This page is one of thousands in the PainScience.com 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 wherever possible.

Is the Functional Movement Screen accurate? Who knows: “virtually no investigations have probed the accuracy of FMS grades assigned by a manual tester.” So Whiteside et al probed it! They compared “the FMS scores assigned by a certified FMS tester to those measured by an objective inertial-based motion capture system.” Alas for FMS, the results were “poor”:

Manual grading may not provide a valid measurement instrument. The levels of agreement between the two grading methods were poor in all six FMS exercises. It appears that manual grading of the FMS is confounded by vague grading criteria.

The discussion section of the article is detailed, readable, and full of ominous understatement. “Dubious grading presents a concern for FMS clientele,” they write. They graciously allow that, with better objective criteria, FMS grading might “improve to acceptable levels.” Meanwhile, FMS testers are officially encouraged to aim for lower scores when in doubt, but in this test, even under scrutiny, apparently they didn’t have much self-doubt, consistently scoring “0.54 points higher than the IMU system.” (I’m shocked, simply shocked, to learn that FMS practitioners might be a tad overconfident!) The authors also point out that FMS has not only failed to reliably forecast injuries, but all FMS predictions may be “a product of specious grading.” Which is hardly surprising, since FMS fails to take into account “several factors that contribute to musculoskeletal injury.” These concerns must be addressed “before the FMS can be considered a reliable injury screening tool.”

Clearly more research is needed — of course! Naturally! But it’s worse than that:

The high potential for subjective and/or inaccurate grading implies that standard procedures must be developed before FMS performance and injury rates can be conclusively studied.

Before it can be studied. They seem to be saying that not only is the cart is still in front of the FMS horse, the horse may now be falling well behind. FMS research so far may be a bit of a write-off, because it can’t inform us without better criteria, and everyone should probably just go back to the drawing board and try again.

~ Paul Ingraham

original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.

Although inter-and intra-tester reliability has been a common theme in Functional Movement Screen (FMS) research, the criterion validity of manual grading is yet to be comprehensively examined. This study aimed to compare the FMS scores assigned by a certified FMS tester to those measured by an objective inertial-based motion capture system (IMU). Eleven female Division I collegiate athletes performed six FMS exercises and were manually graded by a tester. Explicit kinematic thresholds were formulated to correspond to each of the grading criteria for each FMS exercise and then used to grade athletes objectively using the IMU data. The levels of agreement between the two grading methods were poor in all six FMS exercises. It appears that manual grading of the FMS is confounded by vague grading criteria. More explicit grading guidelines would likely improve the uniformity and accuracy of manual FMS grading and also facilitate the use of objective measurement systems in the grading process. Contrary to the approach that has been employed in several previous studies, the potential for subjective and/or inaccurate FMS grading insinuates that it may be inappropriate to assume that manual FMS grading provides a valid measurement tool. Consequently, the development and criterion validation of uniform grading procedures must precede research attempting to link FMS performance and injury rates. With manual grading methods seemingly susceptible to error, the FMS should be used cautiously to direct strength and/or conditioning programs.

original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.

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