Omega Statistics Blog

Developing a Research Question: The Testable Triad

You’ve finished your literature review. Great News! Now you can develop a research question for your dissertation or research!

If that last statement gives you a sense of dread rather than anticipation, it isn’t as bad as you think.

Think relationships. Most studies, at least the quantitative studies, have at the minimum two concepts or variables. The trick is to think of a way to test the relationship between them. The variable can be defined simply as follows:

Independent Variable: This can be a grouping variable like gender (male vs. female), or a predictor variable such as intelligence quotient (IQ) or age.

Dependent Variable: This is your outcome variable, or the endpoint you are testing. An example might be emotional intelligence. Or perhaps in a clinical study, the endpoint might be weight loss.

Two variables is a good start, especially for clinical research. For example, looking at the effects of a weight loss product (change in weight, the dependent variable) between genders (the independent variable) works great. Easy-peasy.

However, testing the relationship between two variables is usually not very compelling in a dissertation framework. But, including a third variable can make all the difference. This concept, the Testable Triad, will add sizzle and depth to your research question.

Let’s look at the process of using the Testable Triad, using some of the variables I’ve mentioned above.

I want to see if there is a relationship between gender and emotional intelligence. That is nice, but it has been done before and my literature review shows that women tend to do better with empathy, and males tend to do better with management of negative emotions. So perhaps I need to look at just one aspect of emotional intelligence as my outcome.

So I will choose empathy as my dependent variable. And now my two-variable research question is:

Two-Variable Research Question: “Do males and females differ on their levels of empathy?”

It is kind of boring, and it doesn’t contribute much to what is already out there. So, let’s consider a third variable that might affect or change the association between gender and empathy. This third variable can be thought of in one of two ways, as a mediator or as a moderator.

Mediator Variable: When included in a model, the mediator variable will account for all of the relationship between the variables of gender and empathy, or will partially account for the relationship

Examples of mediator variables could be IQ, age, or perhaps age group. For instance, levels of empathy may have nothing to do with gender once you take into account an individual’s IQ level or age. I decide to use IQ as a mediator in my testable triad. And I would word my research question as follows:

Testable Triad Research Question: “Does IQ level mediate the relationship between gender and empathy?”

In plain English, I would be testing to see if IQ totally, or partially, accounts for the levels of empathy. It could be that gender doesn’t matter at all once you take into account IQ. Now that is much more interesting, isn’t it?

Moderator Variable: A moderator variable can affect the magnitude or even the direction of the relationship between two variables. Often, a moderator is a grouping type of variable, such as age group rather than age. But not always!

Examples of moderator variables could be: IQ classification with 4 levels (below average, average, above average, exceptionally high) or maybe age group with two levels (below 40 years of age, 40 year of age of older).

As an example, the relationship between gender and empathy may change according to the level of IQ of a person, or according to the age group a person belongs to. And I could word my question as follows:

Testable Triad Research Question: “Does IQ classification moderate the relationship between gender and empathy?”

In plain English, I would be testing to see if the difference in empathy between men and women is moderated (changed) according to what IQ group the gender groups were in. Maybe those with lower IQ levels have more empathy no matter what gender they are, but people with higher IQ levels are not very empathetic. OR maybe the women stay empathetic but the men change depending on IQ level. OR… well you get it, right? IQ level may be doing some interesting things to that gender/empathy relationship.


    Think about YOUR study. Depending on what your literature review revealed, the theoretical framework of your model, and the gap(s) in the research, you could think of many “third” variables for your testable-triad.

    Make a list of these possible mediators and moderators, and choose one (or more, your research question doesn’t have to use only three variables, it doesn’t have to be a triad…but don’t overdo it, remember to keep it simple yet informative) that can be used to tweak what is already in the literature base a bit to look at a concepts in a more in-depth or slightly novel way.

    A final note: The clinical research example I presented earlier, with gender and change in weight as variables, could also benefit from the testable triad: I could use gender as the independent variable, change in weight as the dependent variable, and hours of weekly exercise as a mediating variable…or perhaps exercise type as a moderator.

    I hope the testable triad proves useful to your research.

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