N=1…It Works Because I Said So!!!

The concept of N=1 is well understood and prevalent in those who dabble in research and practice evidence based medicine. It is of course “conducting and experiment” with one subject  (N=1). Whether that be on yourself, your friend, or your patient. The parameters are usually poorly controlled, and there will obviously be a high degree of examiner bias without blinding and randomization. However this rationale exists for many treatments/programs that people seek out or clinicians apply. It basically boils down to “this worked on my friend so I need it too”, “this worked for me”, “this worked on that other patient”,  or “that guy did this and got amazing results therefore it should work for me”. Ahhh, the good ole he said she said. 

The world of physical therapy, chiropractic, naturopathy, nutrition, and strength and conditioning tend to develop a lot of “Gurus” that claim to have found the answer for everything. They claim that their intervention is the answer and the way to treat ALL patients. Whether it be manipulating the OA joint cures all ailments, all your vertebrae are out of alignment, fixing posture is the key, strengthening the core fixes all back pain, scraping soft tissue with butter knives, myofascial release, “carbs are the enemy”, gluten causes all illness in the world, “take this 100C solution of oregano oil to cure your chronic lyme disease”, stretch your fascia to allow for maximum muscle hypertrophy, train arms 17 times a week for maximum hypertrophy, etc. The list goes on and on with hundreds of examples that are not supported or even contradicted by best evidence.

The problem is that these people usually have silver tongues and their marketing is far far far better than whatever snake oil they are selling. They often use lofty claims (like getting everyone better in 3 visits http://www.airrosti.com/what-is-airrosti/) about how many people they have/can cure, and that you have wasted the last X amount of years treating all your patients the wrong way. When you ask why you will get the “because I said so! How dare you question the sage wisdom of the guru!.” Often times they honestly and wholeheartedly believe that what they are saying is true. This could be due to multiple phenomenon such as examiner bias, inaccurate patient feedback, placebo effect, and regression to the mean to name a few. 

These “gurus” tend to be unwilling to change their opinions when presented with compelling evidence to the contrary of what they believe. I believe that they start out with very honest intentions to help people and do something that they see results with. This then grows based on a speculative reason as to why said results happens which inevitably leads down a self-confirming path taking as many followers along as possible to bolster their creditability.

I am no exception to the rule and have had to unlearn many ideas that were taught to me in physical therapy school such as reliability of palpation, specific vertebral manipulation, innominate rotation, ultrasound, stretching fascia, etc. Additionally I sometimes struggle to not immediately jump to a specific treatment for a patient that I have had success with on similar patients in the past. Not every patient is the same or will have the same(most likely non-specific)  reaction to that intervention as the last. 

I am by no means trying to say that all of these programs/treatments haven’t ever or don’t work for some people. I have seen patients somehow get significant relief from scraping a butter knife on their plantar fascia for plantar fasciitis, people have sig less pain from myofascial release, knee pain disappear with foam rolling the IT band, back pain diminish with a naturopathic remedy, etc. I am only trying to suggest that in many cases the mechanism of action most likely is not at all what said treatment proposes to do. 

It is imperative that we always examine claims with a discerning eye and examine the body of evidence to make an informed decision for ourselves and more importantly our patients. Be wary of the N=1 and all the gurus out there. There have always been gurus and there always will be gurus. It is your job as a health/fitness/medical professional to make educated treatment choices. 

As always, stay skeptical and keep reading,

Jarod Hall, PT, DPT, CSCS

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