Whether you are testing a new product, packaging idea, creative design, or any other type of stimulus, you have probably been conflicted with which testing method is best. As in most research ventures, the optimal solution will vary based on the number of concepts you are testing, your budget, and your research objectives. There are many product testing design variations to address your unique situation.
Monadic testing involves providing the respondent with one individual concept, product, or other isolated stimulus. The stimulus is shown and evaluated alone, separate from any other concepts. Testing a concept alone allows for a completely clean read on each piece of stimuli and has many advantages. Each concept is evaluated without being biased by the influence of the other concepts. It eliminates the interaction between different designs, and it simulates real life since we usually interact with products one at a time. Allowing the respondent to focus their attention on one stimuli results in the most accurate and actionable diagnostic information. Because you are only showing one stimuli, you can ask more questions and garner more detailed feedback without fatiguing respondents. Consider including a current and/or competitive offering in the monadic test as a control so you have a benchmark when analyzing the results.
Sequential Monadic Testing
Sequential monadic testing involves showing one piece of stimulus at a time, however, respondents will also be shown another alternative concept or several additional concepts. In this design, each respondent sees one product and evaluates it, then sees the second product and evaluates it, and so on. The sequential monadic design is an excellent option for understanding small differences and preferences between two 2 or more concepts. However, there are a few things to take into consideration. Because more than one concept will be shown, there can be a risk for order bias. Therefore, it is recommended to randomly change the order or sequence in which the concepts are presented each time. In sequential monadic testing, we witness what is known as a “suppression effect” whereby all the scores are lower compared to a pure monadic test. This means the results from sequential monadic tests cannot be compared to the results from monadic tests. Additionally, an “interaction effect” is at work in sequential monadic designs. If one of the two (or more) products is exceptionally good, then the other product's test scores are disproportionately lower, and vice versa.
This design is exactly as described where the respondent is shown two products and asked to choose which is preferred in the pairing. An advantage of this test is that it can measure very small differences between two products, yet a big disadvantage is that it will not reveal if both products are very good or both are very bad.
The protomonadic design starts just as a monadic test, but is followed by a paired-comparison. Sequential monadic tests are often also followed by a paired-comparison test. The protomonadic design yields good diagnostic data and the paired-comparison test at the end can be thought of as an extra layer of validation to ensure that the results are correct.
The Key Takeaway
As with any research project, make sure you clearly define your objectives and understand what kind of testing will best help you meet your goals while staying within your budget. The number of concepts you need to test, whether or not you need comparative data, and your budget will be some of the main factors to consider when choosing among different testing methods.