Evidence Based Medicine

Research versus Evidence Based Medicine

Many physical therapy bloggers talk frequently about evidence based medicine. Often, though, these bloggers don’t agree with each other on treatments.  Usually, they seem very focused on the research.  While I support reviewing the research, I remember evidence based medicine including more than just research.  That’s right, it’s not just research.  So if research is not the only component, what else does it include?  Evidence based medicine, a triad, includes research, clinical experience, and the individual.  However, some have gotten so focused on the research, that they completely overlook the clinical experience and the individual.  My NDT instructor once said that we have stopped teaching students technique and started teaching them research.  Now students do really good research to prove their poor techniques don’t work.

My Case Study

In grad school, I was gung ho about research.  I planned on using it for the basis of my treatment.  Then, I started my clinicals.  My doubts first started while working with a man with an ACL replacement.  His knee extension was struggling; it was around -25 degrees.  My clinical instructor did a lot of massage even though the research didn’t support massage.  I had to go along with it, even though I didn’t really feel like it helped.  He had a huge knot (I know a lot of you don’t like the term, but you know what it is) in his hamstring.  With some massage, the knot went away, and he gained 10 degrees of knee extension.  He maintained the benefits we got from that massage, though after that, he didn’t really seem to benefit from massage as notably.

Duplicating that event for research would be incredibly challenging.   The research would group him with other ACL replacements who didn’t have those knots. The research ends up showing that the technique doesn’t work, and they dismiss it.  Unfortunately, students end up losing a valuable resource to help their patients.

Understanding the limitations of research will help us apply research properly.  So, let’s review the flaws.

• It measures one very small variable. I remember reading through research, writing up CATs, and feeling incredibly frustrated with how I spend several hours reviewing a research article only to gain a tiny bit of information.  If I read a study on joint mobs to the shoulder for frozen shoulder, the only information I get out of it is whether the number of joint mobs done in that study helped frozen shoulder.  It didn’t tell me whether doing more joint mobs would help: it didn’t tell if it would help another diagnosis: it didn’t tell me whether it would help the elbow, hip, or knee.

 

• Research doesn’t always account for different causes of pain. Numerous studies review McKenzie technique to Williams.  These studies often have a huge flaw: they don’t look at the cause of the pain.  It turns out that when McKenzie developed his technique, he worked with primarily young athletes.  Williams worked primarily with seniors.  They often treated different conditions and therefore, got different outcomes.  So, depending on the cause of the pain, the different treatments worked.  Eventually, researchers figured this out.  However, there are so many different causes of pain, that research becomes incredibly difficult.  (McKenzie did eventually acknowledge this difference and did a better job adjusting his technique for both types of patient.  Early research, though, did not include this adjustment).  Keep in mind, when reviewing research, if it really explores the causes of pain.  Are you having success with a technique that the research discounts?  Can you figure out which patients it seems to help?

 

• Be wary of research that disproves certain theories, but doesn’t actually take the time to understand the theory. I read many blogs that conclude a certain technique doesn’t work.  Or that a certain theory can’t be true based off some research they read.  Often, though, when I read the study, the researchers test a theory similar to the proposed theory, but it isn’t actually the theory itself.  For example, many bloggers claim that fascia doesn’t release because it is too strong.  A friend of mine referenced a study where the ITband was attached to a truck, they slowly increased the speed of the truck to increase the resistance of the ITband. They wanted to see if it would release: it never did.  It tore before it released.  My friend concluded from this research that fascia is too strong and cannot be released. However,
  1. Fascia is three dimensional, it does not release in a linear direction, so applying pressure that way will not help
  2. This research occurred on a dead piece of tissue
  3. The connective tissue cannot be engaged, sunk into properly when you pull on it with a truck. I’m not trying to convince anyone reading this that fascia releases; I’m just pointing out that this study does not disprove it.

 

• Variability of humans. This point tailbacks off of my second point, but it is too important to miss.  Researchers in physics can often completely control the design.  We can create the exact same conditions for the research to repeat the study over and over again and therefore get the same results.  However, you can never recreate the exact same conditions in studies with humans: never.  Even when you do the initial study, the human bodies are all different.  When you recreate the study, it becomes even harder.  No research done on humans can ever meet the full requirements for research: EVER.  Researchers can never truly recreate a study on humans the way they can with physics.

Incorporate Research Effectively

Please do not use this to completely disregard regard research or quit using it.  I certainly use it myself. I do ask you to put it into its proper context.  If you have success with a certain treatment, I would show caution before stopping it based on one study.  People often state that research helps rule out biases and placebo effects.  When it comes to pain, though, placebo effects have their advantages.  I will probably get a lot of heat for the article.  It is too important, though, to ignore.  It needs to be said.  I have read articles from too many evidence based practitioners who disprove every technique used in physical therapy.  Yet, I keep reading studies about how much physical therapy helps with pain.  Don’t disregard what happens right in front of your eyes because of one study said it shouldn’t work.