What is evidence based practice?

What does “evidence-based” mean?

The health and fitness industry is full of professionals and influencers making statements that are “evidence-based”, “based on the latest research” and “scientifically proven”. This all sounds great to most of us, but what does it actually mean? This article outlines the most reliable types of research, the concept of “cherry-picking”, as well as what an evidence-based therapist is.

How do I know if my health practitioner is evidence-based?

Physiotherapy is a well-known evidence-base profession that is constantly evolving and changing as new research comes out. In addition, Physiotherapists are governed by the Australian Health Practitioner Regulation Agency (AHPRA) and the Physiotherapy Board of Australia which have many rules and regulations that therapists must adhere to to maintain their license to practice, including completing ongoing professional development each year.

True evidence-based physiotherapists will use information from the most recent, high-quality systematic reviews and randomised-controlled trials to best inform their clinical practice, and will also know how to assess whether a study is of good quality. They will only take on findings from lower quality studies with caution.

Evidence-based also means that said clinician’s have reliable ways of staying up-to-date with the latest, most relevant, and high-quality evidence so that their practice can evolve alongside research findings. This is an immense task as thousands and thousands of new research papers are published every day around the world so it is easy to fall out-of-date.

In addition, evidence-based practitioners combine their knowledge of the research with their clinical experience and what the client expects, believes or desires. For example, the evidence about the first line treatment for osteoarthritis is quite clear, however no two people will have the same treatment experience.

Not all research is good research

If you’re someone who hasn’t learned about scientific research principles and how to interpret data, seeing a statement with a link to an article that looks something like this can make you feel as though what’s being said is pretty reliable and can be taken as a fact.

What many don’t realise, including many people making claims, is that not all research is good research. There are certain types of papers that’s findings are more accurate than others, and even within those articles, there are many factors that can impact their quality and therefore the likelihood of the results being actually true.

The first thing you need to know is the levels of research, which can be seen in this image. The levels at the bottom are the least reliable, and the filtered information at the top is the most reliable. 

Although the paper above looks reliable to most people, it is based on case studies, meaning its results should not be taken as fact. It is not to say that its results wouldn’t match higher quality studies, but it is unwise to use this level of evidence on its own due to the high risk of bias and error.

“Cherry-picking”

When a paper like the one above is used on its own to back up statements, it is called “cherry-picking”. This means it has been selectively chosen to support a claim as opposed to all of the available research being referenced.

This often occurs unknowingly with the best intentions by professionals who don’t have training in scientific degrees, so are unable to assess the type and quality of information that is being used to base a claim on.

A common example of this in the health and fitness industry is claims that ‘slouching’ postures are bad and more upright postures are good for you, even though the most robust evidence doesn’t support these claims (a more accurate statement is that any sustained posture is a problem; increasing movement is better than simply changing to a different sustained posture).

The most reliable evidence – Systematic Reviews

Systematic reviews are the most reliable forms of evidence (the top of the pyramid above). They are essentially a summary of the best available research on a particular topic.

They summarise and often statistically analyse the findings of all of the available studies on a topic. When done well, these papers conclude the overall findings by weighing up individual study qualities so as to ensure results from high quality studies have more weight than those of poorer quality, resulting is a much more reliable conclusion than a stand-alone study.

High quality systematic reviews will generally only include studies called randomised controlled trials (RCTs). 

The next best thing – Randomised Controlled Trials (RCT)

When done well, RCTs are the best way to study the safety and efficacy of new treatments as they aim to reduce the amount of biases present, prevent systematic errors, and use proper analytical techniques. They aim to compare at least one treatment to a control group or another treatment (eg. surgery vs exercise, or surgery vs control group).

There are many elements that go into a good quality RCT including patients, assessors and clinicians not knowing who is in which group, having a large number of people involved in the study, and other more specific statistical requirements.

In conclusion

If you don’t have a thorough understanding of research and scientific methods, looking at research articles yourself is most likely adding more ‘noise’ and confusion to the question you are trying to answer. The best place to get evidence-based health care is through a therapist who has training in a health-based science degree, such as doctors, physiotherapists, dieticians, psychologists, etc.