Quantitative Research Designs: Descriptive non-experimental, Quasi-experimental or Experimental?

Quantitative Research Designs: Descriptive non-experimental, Quasi-experimental or Experimental?


Students often have difficulty classifying
quantitative research designs. In quantitative research, designs can be classified into one
of three categories: descriptive non-experimental, quasi-experimental or experimental. To identify
which of these designs your study is using follow the steps in this video.
First, ask yourself if the researchers did anything to the participants. More specifically,
was there an intervention? Interventions include things like support
groups, educational sessions, treatments for a condition or some other variable that is
being tested. If people would not normally have something without being in the study
but the researcher gives it to them to see what it will do than that is an intervention.
You may also see research texts call this a manipulation. Essentially, the researcher
did something to people to provoke some kind of measurable result.
If the answer is yes, there was an intervention, then the study is either a quasi-experimental
or experimental. I will tell you how to decide in a moment.
If the answer is no, the study is descriptive non-experimental. Sure, you could be more
specific in the description of the design, but for the purposes of grouping your research
in a literature review this label is often sufficient at an undergraduate level.
Descriptive non-experimental studies may also be called observational. Some examples of
more specific labels include case control, cohort and correlational studies. For more
information about these non-experimental designs please visit the research playlist below this
video and watch the video about research paradigms and methodology.
To find out if the design is experimental ask yourself if it is a randomized controlled
trial. Randomized controlled trials are considered the gold standard or “best” possible design
(in quantitative research). You may also hear randomized controlled trails referred to as
true experiments. However, in the real world it is difficult to conduct a true randomized
controlled trial in many situations, which means that a lot of studies are done that
are not classified as randomized controlled trials.
Randomized control trials have three key components: a random sample, a control group and an intervention.
If your study is truly a randomized control trial it should say in the abstract and/or
the methods section of the article. If it doesn’t say then it is likely that the study
is either descriptive non-experimental or quasi-experimental. You can tell the difference
by looking into the methods section further. Recall that if the intervention is missing
the study is not an experiment. As we just discussed, this type of research is observational
in nature and therefore is classified as a descriptive non-experimental study.
If there is no control group than the study is quasi-experimental. A control group is
a group of people that enter the study but do not receive the intervention under study.
Instead, they are used for the purpose of comparison.
If the sample was not randomized properly or adequately or even at all then the study
is also quasi-experimental. You may also see this type of study being called a non-randomized
trial. Many randomization strategies exist, but basically if a study is randomized it
means that everyone who entered the study had an equal chance of receiving the intervention
under study. You may see some studies indicate that they were partially randomized. These
studies still do not count as true experiments. If your study has a random sample, control
group and intervention than it is a randomized control trial.
Sometimes I see students that are confused about the study design because of terms that
relate to the length of time the study was conducted or the sampling process. While you
are right that these terms relate to study designs they are not broad enough to represent
the methodology of the study and therefore do not give enough information to the reader
about the study design. Terms like cross-sectional and longitudinal
tell you how much time the study was conducted over. Cross sectional means that data were
collected at one point in time. Longitudinal means that data were collected over a long
period of time. These terms alone will not tell you if the study is descriptive non-experimental,
quasi-experimental or experimental. If you use these words to describe your study design
in the absence of one of the labels we discussed in this video you will not have given your
teacher enough information about the study design to properly classify it.
Other confusing terms often relate to the way samples were collected, like convenience
sampling. Convenience sampling means that the sample was readily available or accessible
to the researchers. This term will give you the hint that the study does not have a random
sample and is therefore not a randomized controlled trial, but you still need to classify it further
as descriptive non-experimental or quasi-experimental. To decide how to classify the design of a
study you are looking at, follow the steps outlined in this video. Ask yourself the following
three questions: Was there an intervention?
Is there a control group? Was the sample random?
The answer to these questions will tell you how to classify the design of any quantitative
study into one of these three categories: descriptive non-experimental, quasi-experimental
or experimental. Check with your teacher to see what other labels they may be expecting
in the description of your research design just in case they want more detail.
If you are looking for more detailed information you are welcome to check out my eBook or related
videos. The eBook is best in PDF format, but is also available in other formats at the
links below this video. If there is anything else you need please comment to let me know
and subscribe so you can keep up to date with videos as they are released. Thank You.

94 thoughts on “Quantitative Research Designs: Descriptive non-experimental, Quasi-experimental or Experimental?

  1. I love the video. I would like for you to make a video on how do  you support your  study relationship based on a theoretical or conceptual framework.  

  2. Thanks so much for simplifying a subject that has been challenging me for the last several weeks. I wish I would have found you sooner but think I can now address my professors questions with much more intelligence and insight.

  3. Thanks for the videos. I teach online and I often post your videos (with citation of course). Do you have any videos about spss software?

  4. Hi Nurse, would you please explain about quantitative correlation and its related research question? What is the difference between correlational and  Quasi-experimental?Sofia-PhD Student

  5. this is very useful video described in simple manner… how can we access to other videos…??? pls send the links

  6. I am in accounting research class, having problem with research design, thanks to your video I now understand a lot better!!!
    Thank you!

  7. If i was trying to asses whether therapeutic success is the result of a positive client and therapist relationship. It involves just getting client to fill out questionnaires over the period of their therapy . Is this non experimental/ What type of non experimental?

  8. This video was amazing and helped to make Research not so confusing! I even shared this with my research class. Thanks so much!!!

  9. NurseKillam, you are the best online tutor. As a matter of fact, my professor has 2 doctorial degrees and he is not as clear and direct as your teaching. Are you really a NURSE??

  10. Goodness, this video is very detail,now I can proceed with my paper.Thank you NurseKillman.I believe that you should give my professor a refresher course.

  11. very helpful lecture
    i want to get your book but it show to me this message
    Sorry! Books on Google Play is not available in your country yet.
    We're working to bring the content you love to more countries as quickly as possible.
    Please check back again soon.
    if you can send it to my email
    [email protected]
    thanks alot

  12. I am so glad that I have found you. The article that I am critiquing uses a prospective cohort study, there are no intervention. Before terming the quantitative method as non-experimental descriptive, how do you know its descriptive?

    Hope to hear from you soon.

  13. Hi. I'm trying to determine what a research design would be in this situation: whether an online tutorial had any effect on the number of questions asked about A (a specific event). Basically, looking at statistics of questions asked about A before and after the tutorial was made available online. There really isn't a control or experimental group per se, as we are just looking at statistics.

  14. Hi nursekillam. thank you so much you do not know how discouraged i was until i watched your video.And iam some what know clue about the quasi -experimental. But my colleagues can help me how i can related the title of ,the impact of market oriented beekeeping on house hold farm income .

  15. Hey @Nursekillam love your vids, they are very helpful. Could you tell me how to figure out the population in a study if it was 3 trained research assistants watching videos of 2 TV shows to mine for data for a quantitative study. Would the TV shows be the population, or is there no population? I'm so confused.

  16. Designing my own research for the first time and I must say working out the study design, the size of the sample, statistical power, choosing the right measurements and so on can be daunting! I found your video very helpful although I am still unsure of what to call my study?! 😀

  17. this is so beautiful! i hav had challenges in understnding this but u hit it right on point! thanks. i would like to learn about the phylosophy of science the guide different types of research

  18. Thank you for sharing this video. It was a big help! I have a couple of questions though… Is it convenience sampling in a school setting where the researcher has to get permission for students to participate in the study when only a few students give permission to participate? If it is convenience sampling and students are randomly assigned to groups does that make the study experimental or quasi experimental? Thanks for your help.

  19. Hello,Your video was extremely helpful.
    I am doing some research on alcohol consumption in pregrnancy in relation to post partum depression, in this case I want to do purposeful sampling and divide the mothers who consume alcohol in one group and who donot consume alcohol in other group. I think ramdom sampling cannot be done here. However, I want to put both the groups under same test giving equal chance with same intervention to find co relation. So, is this a quasi experiemental design or not ? If not then what is my research design.
    Please advice me soon if you have time.
    Thank you

  20. Our teacher is having us identify which statistical test to use based on Research Question scenarios. Happen to have a video on how to identify terms to clue us in on which stats hypothesis test to apply. i.e. One Sample T-test, Two Sample t-test, z-tests, Two-way Anova, Chi-square Goodness of fit, etc…?

  21. Thank you so much for your short but very effective video. I am really benefited. As I have an exam. it will be helpful for me.

  22. This was SO helpful. I knew the heart of my research design but I didn't really know how to approach the description for the methodology of my design. I couldn't distinguish between correlational or causal-comparative or not. After watching this, I know my particular design is neither of those. THANKS!!

  23. My current teacher and the textbook she uses told me information that contradicts this video. According to them, for a study to be experimental it is only necessary that assignment to the experimental or control group, not sampling, be random.

  24. hi, I am really stuck on a paper I have been given along with some questions and I was wondering If u could take a look at it…. I have answered some of the questions using ur videos that have helped me understand ontology, epistemology. do u have an email where I could send the paper over to u?

  25. In my experiment, units are selected in random and there is no control group.It is pre-post experiment and my pre observation act as a control group.can i categorized as quasi experiment. what is the best sample size fro such experiment which would use non parametric method? Useful flow chart and thank you for best explanation.

  26. You need to write the research book.!!!!The reason why everyone finds research difficult its because the books are written by someone who know research well not taking in consideration others like us who have no clue. Thank you for sharing your teaching expertise.

  27. Thanks, it is very brief and clear. I will use this for the introduction of quantitative research in my class. I hope you wouldn't mine.

  28. I'm a novice researcher. Is there any way you could place your videos in order as to what you think would be first to watch and following starting with quantitative research?

  29. Despite your very fabulous way of simplifying research concepts, I am still at a loss deciding on the methodology to pursue in my study.. I hope you could provide some help!

  30. Thank you very much for the clear explanation. I do rarely comment but I couldn't hold myself . Excellent

  31. I spent days trying to understand these concepts and because of you, I finally understand! I know it is frowned up[on in the research world, but youtube is the best source for finding information on any topic.

  32. I found your video very easy to follow and informative. The flowchart is useful, easy to follow and provided the clarification I needed. Thank you

  33. Please i need help .. if i have a data of qusai experimental
    Qusai experimental non equivalent control pretest post test design…
    Which statistical i will use for this…
    Kindly let me know

  34. Thank you for the clarity. This link was key in helping me grasp the subtle differences in quantitative research study designs.

  35. Uh oh! You got a typo. The bubble that pops up says "Random Comtrolled." Great video otherwise. Thanks for the help.

  36. Thank you! Thank you! Thank you! I learned more in 6 minutes and 37 seconds than I did in hours of reading textbooks.

  37. Omg made life easier thank you so much. And you have a beautiful voice. Very easy 😫😫 I wish you were my teacher

  38. Hey guys. Supposing you cannot apply a true experimental research design but you still want to follow a quantitative research design, what research can you do?

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