The phrases “according to one study” and “some studies suggest” have become so common that the appeal to studies is now the butt of many jokes. It’s hard to get through a news program or article without encountering some variation of these phrases, and for good reason: Studies can lend scientific perspective and credence to the views we discuss. This can help us avoid arguments that are skewed by empty rhetoric and false impressions.
Those of us in the field of health and wellness rely on studies heavily to learn about causes of and treatments for health conditions, such as chronic back pain. Research is important, as it helps us understand how to prevent and manage pain safely and to know what the dangers of certain treatment methods are.
But sometimes appeals to studies, whether in the health and wellness niche or other areas, can stray from their positive purpose of getting us closer to the truth. Sometimes, such appeals can actually lead us astray.
There are a number of reasons for this, one of the most obvious being a failure to properly understand what a study suggests. This could manifest as a substantial misinterpretation.
But perhaps a more ubiquitous reason why studies are often misunderstood is that not enough attention is paid in public discourse to the different levels of evidence studies may attain to. Rarely if ever can a study be said to “prove” something. The best studies provide such reliable evidence in support of a conclusion that it would be unreasonable to doubt it, but most studies fall more into the category of “suggesting” a possible conclusion – or none at all – and provide guidance for further research.
Quality studies contain a section devoted to a discussion of the limitations of the study and any flaws in its design. This section is normally found after the conclusion or discussion section. Seek “Limitations” sections out before drawing any firm conclusions.
Below is a list of the five levels of scientific evidence studies attain to that can help you situate the studies you encounter. The levels are listed in order from most to least evidential.