Importance of Replication Studies

By Kalista Arendt

What is a replication study?

To begin, let us discuss what exactly this is.  A replication study is a study where the researchers are using the methods section of a research study that has already been replicated to look at the validity of the research.  Having good validity is crucial because it tells us that the study is accurate and measuring what it is supposed to be measuring.  This is why it is so important when you are writing the manuscript to make sure that your methods section is as clear as possible.  It may seem like you are oversimplifying things, but it is important to the reader to understand how you collected your data and to be able to replicate the study if they want to. Replicating research is a great way to learn how to do research because the methods section is already laid out for you.  The hard part is done.  In Psychology 301: Research Methods, a large portion of the class was dedicated to finding, researching, and replicating a research study.  Our professors made sure that we understood exactly what was expected of us.  They helped us to learn what statistical procedures were used.  Sometimes, the studies used complex statistical methods that we were not taught in basic statistics.  This course is particularly daunting to almost every psychology major.  However, the professors are really helpful and there when you need them.  

How do you replicate a study?

To replicate a study, you must read the manuscript for the study.  It is important that you have a clear understanding of its purpose.  Understanding the background and conclusions from the study are critical.  Most importantly, this should be a study that you are interested in.  To stay motivated through the long hours of preparing the study, collecting data, analyzing the data, and publishing it, you need to have an interest in it.  Do not choose a study that you just think will be easy.  Chances are that enough people have already studied it to establish the validity that it needs anyways.  Now that you have a firm understanding of the study that you want to replicate, you need to look at the methods section of the manuscript in detail.  Look at parts that you want to replicate.  Oftentimes, the researchers will have multiple parts or independent variables that they are studying.  You can replicate all of them if you want, but make sure that you are able to put your best effort into it.  That is why people will sometimes only research one part.  Now that you understand the methods section, you are able to create your own set of procedures, collection materials, and script for the research.  It is important to have a script when you are collecting data so that you are giving the same instructions to everyone that is participating.  This will help you make your data more reliable.  It will also help you to be less nervous when you are giving the instructions to people.  I know this was something that I was nervous about because I collected data in groups of four.  Now that you have all of your materials, it is time to put together your IRB application.  This is important to make sure that your study is following the ethical procedures.  Once your IRB application is complete, you should submit it, and wait for approval.  Once it is approved, you are ready to start collecting data.

I found collecting data to be the most exciting part of the research.  You get to see patterns in your data.  Sometimes you will have expected those patterns, and other times, you will be surprised by what you learn.  Since this is a replication study, you probably have some idea what to expect.  The amount of data you collect depends on how long and how many spots you have available for your research.  Once you have collected a good amount of data which depends on what your goal is, you are ready to analyze the data.  This helps you to see trends and patterns in a more concrete way than just looking at it as you are collecting it.  Finally, you should prepare a manuscript.  You can then compare your results with the results of the original study.  You may even decide to present your findings at a conference to share your results with the rest of the psychology community.

Why replicate a study when it has already been researched?

This is an excellent and practical question.  Everyone wants to be the person who discovers a novel thing.  However, it is important that we make sure that the studies already replicated are valid and reliable.  In psychology, there has been a “Replication Crisis.”  Moreover, a lot of psychological principles are being questioned because people are starting to replicate them, but finding nonsignificant results.  This makes people in the psychology field question foundational research.  To read more about this replication crisis, click here.  Back to why we need to replicate research.  If the researcher messed with the numbers, this would be fraud.  The only way to catch this is if researchers replicate the study.  Replication study is important in the medical and health field because if a drug works for one person but not another, then the question of whether it is a good drug comes into question.  There can also be a false positive, or false statistical significance, but without a replication study, nobody can find it.  My replication study from Psych 301 was interesting because we got insignificant results even though the original study claimed significant findings.  We were worried that we did something wrong.  However, after reading more about the study, there were 17 other replication studies, and they also found insignificant results.  Maybe the idea behind the study is true, but the collection and observation of it is wrong.  It is also important to keep in mind that things change throughout the years.  If the researchers asked participants to rate the funniest of a cartoon from the 50s in the 50s, that would be different from if researchers asked participants to rate the funniness of cartoons from the 50s in 2020.

All in all, it is important to replicate studies because it helps support the validity of the original research.  Sometimes changes need to be made to the procedures, but that is okay in moderation.

Some additional resources:

https://www.verywellmind.com/what-is-replication-2795802#:~:text=When%20studies%20are%20replicated%20and,generalized%20to%20the%20larger%20population.

https://www.enago.com/academy/importance-of-replication-studies/

https://www.popsci.com/what-is-replication-crisis/