How to Interpret Scientific Studies (Part 2)

How to Interpret Scientific Studies (Part 2)

The best way to keep up to date with the latest scientific research is to go straight to the source and read scientific studies. Last week, we provided some simple guidelines to help you interpret them. Today, we'll take a look at a couple of scientific studies that caught our attention and interpret them using our guidelines.

Scientist holding a flask

The best way to keep up to date with the latest scientific research is to go straight to the source and read scientific studies. But studies can be difficult to read and understand. So, in last week's post, we provided some simple guidelines to help you interpret them.

In today's post, we'll take a look at a couple of scientific studies that caught our attention and interpret them using the guidelines in our previous post. So, next time you want to make sense of a scientific study, be sure to reference this 2-part post.

The Studies

We've selected two scientific studies from the past several years. Here are the titles with links to the full studies:

Study 1: Short- and medium-chain fatty acids exhibit antimicrobial activity for oral microorganisms

Study 2: Worldwide trends in body-mass index, underweight, overweight, and obesity from 1975 to 2016: a pooled analysis of 2416 population-based measurement studies in 128·9 million children, adolescents, and adult

In the next part of this post, we'll interpret each study by running them through the 4-step process we outlined in our last post.

Scientist holding a flask

Step 1: Skim Through the Study

First, we'll take a look at the title, keywords, and publication date of each study to get an overview of what they are about and when they were published. We'll also check where the studies were published to make sure that they are reliable. Next, we'll skim through each study and pick out several words or acronyms that are difficult to understand.

Study 1

The title of this study tells us that it is about the antimicrobial activity of short- and medium-chain fatty acids against oral microorganisms. The following keywords are found after the abstract: Short-chain, Medium-chain, Long-chain fatty acids, Antimicrobial activity, Bacterial ecology. These show us the main topics that will be discussed in the study.

The study was published in the Archives of Oral Biology in July 2011. A quick Google search reveals that this is a reputable monthly peer-reviewed journal that was established in 1959.

The study contains several acronyms that may be difficult for the casual reader to understand. However, each acronym is explained the first time it is used. Examples include short-chain fatty acids (SCFAs) and medium-chain fatty acids (MCFAs).

Study 2

The title of this study shows us that it is an analysis of worldwide trends in body-mass index over a given period of time. We can also see that the researchers studied a large group of children, adolescents, and adults. This particular study does not include a list of keywords, but the title gives us a good idea of what it's about.

The study was published in The Lancet, one of the best-known medical journals in the world. Therefore, we can consider the research to be reputable. The study publication date is December 2017. The language used in this study is fairly straightforward, and any acronyms used are explained the first time they are used.

Step 2: Read the Introduction and Discussion

Now that we've skimmed through both studies, we'll go back and read the introductions and discussions. Here are some brief notes about these important sections of the studies:

Study 1

The introduction gives some background information about other research in the field. We learn that fatty acids are produced by oral bacterial strains and have been shown to exhibit strong antimicrobial activity against various oral pathogens. The authors also explain that the main purpose of the study is to find out which fatty acids are most effective at inhibiting oral bacteria.

The discussion provides insights into the findings of the study. Here, we learn that certain LCFAs and MCFAs (including lauric acid) had significant anti-Candida activity. By comparison, some types of fatty acids such as SCFAs had a limited effect against oral fungal species.

Study 2

The first sentence of this introduction is very clear and easy to understand:
"Being underweight, overweight, or obese during childhood and adolescence is associated with adverse health consequences throughout the life-course."

The authors of the study then go on to explain some of these health consequences. The next section of the introduction gives an overview of the research in context. Finally, in the last paragraph of the introduction, the authors state that their aim is to look at worldwide trends in body-mass index. They also explain that this research has never been carried out before.

In the discussion section, we learn that the mean BMI and prevalence of obesity increased worldwide in children and adolescents from 1975 to 2016. Details about trends in different parts of the world are also discussed.

The authors go on to say that although mean BMI has increased, more children and adolescents worldwide are moderately or severely underweight than obese. However, they conclude that: "If post-2000 trends continue, child and adolescent obesity is expected to surpass moderate and severe underweight by 2022." In the final part of the discussion, the authors outline the implications of their findings.

Step 3: Read the Results Section and Abstract

At this stage, we have a pretty good understanding of each study. But it's worth going back and reading the results sections and abstracts. Here are some notes about these sections of the study:

Study 1

The results section of this study is combined with the discussion, so we've already read through it in full. This time, it's worth examining the graphs and tables to gain a better understanding of the effects of different types of fatty acids on the various oral microorganisms.

The abstract is broken down into 4 sections: objectives, methods, results, and conclusions. Although this section is a little difficult to read, it provides a good overview of the entire study. Here, we learn that more research is needed into how fatty acids influence the microbial ecology in the oral cavity.

Study 2

The results section of this study is quite dense, but it contains some useful visual representations of the researchers' findings. For example, in figures 1 and 2, we can see trends in age-standardized BMI by sex and region in males and females. Figure 3 is especially clear and easy to understand. It shows us age-standardized mean BMI, prevalence of obesity, and prevalence of moderate and severe underweight by sex and country in 2016 in children and adolescents.

The abstract in this study is the summary at the beginning of the paper. It is divided into the following sections: background, methods, findings, and interpretation. The interpretation is particularly useful, as it summarizes the findings of the study in the following simple paragraph: "The rising trends in children's and adolescents' BMI have plateaued in many high-income countries, albeit at high levels, but have accelerated in parts of Asia, with trends no longer correlated with those of adults."

Step 4: Consider Different Points of View

Now that we've read the most important sections of the studies, it's time to look for other studies on similar topics. To do this, we'll type some keywords into online academic search engines such as Google Scholar and Pubmed. For example, when we type "medium-chain fatty acids" into Pubmed, we can see that there are 3701 results! We recommend skimming through these entries and looking at the titles of the studies to give you an idea of other research in the field.

Finally, we'll head on over to Google and search for books or articles that reference the studies. When we enter the title of the first study, we can see that it has been referenced by a number of qualified experts. One of these is world-renowned lipids expert, Dr. Bruce Fife, C.N., N.D., who referenced the study in his book, Coconut Therapy for Pets. Similarly, when we enter the title of the second study, we can see that it has been referenced in several reputable publications. This gives us confidence that the studies are generally well regarded by the scientific community.

We're at the end of our 4-step process for interpreting scientific studies. So, now it's over to you! Want to discover more great scientific studies about medium-chain fatty acids and coconut oil? Be sure to check out our previous post.