Custom Product Testing Techniques

Custom Product Testing Techniques

Monadic Research Design

Monadic testing typically is the best method for product testing or product optimization. Testing a product alone offers many advantages. Interaction between products (which occurs in paired-comparison tests) is eliminated. The monadic test simulates real life (that's the way we usually use products—one at a time). By focusing the respondent's attention upon one product, the monadic test provides the most accurate and actionable diagnostic information. Additionally, the monadic design permits the use of normative data and the development of norms and action standards.

Virtually all products can be tested monadically, whereas many products cannot be accurately tested in paired-comparison designs. For example, a product with a very strong flavor (hot peppers, alcohol, etc.) may deaden or inhibit the taste buds so that the respondent cannot really taste the second product.

Sequential Monadic Research Design

Sequential monadic designs are often used to reduce costs. In this design, each respondent evaluates two products (he or she uses one product and evaluates it, then uses the second product and evaluates it). The sequential monadic design works reasonably well in most instances, and it offers some of the same advantages as pure monadic testing.

One must be aware of what we call the “suppression effect” in sequential monadic testing, however. All the test scores will be lower in a sequential monadic design, compared to a pure monadic test. Therefore, the results from sequential monadic tests cannot be compared to results from monadic tests. Also, as in paired-comparison testing, an “interaction effect” is at work in sequential monadic designs. If one of the two products is exceptionally good, then the other product's test scores are disproportionately lower, and vice versa.

Protomonadic Research Design

The protomonadic design (the definition of this term varies greatly from researcher to researcher) begins as a monadic test, followed by a paired-comparison. Often sequential monadic tests are 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 a safety net—as added insurance that the results are correct. The protomonadic design is typically used in central-location taste testing, not in a home use test (because of the complexity of execution in the home).

Paired-Comparison Test

Paired-comparison designs (in which the consumer is asked to use two products and determine which product is better) appeal to our common sense. The paired-comparison is a wonderful design if presenting evidence to a jury because of its “face value” or “face validity.” It can be a very sensitive testing technique (i.e., it can measure very small differences) between two products. Also the paired-comparison test is often less expensive than other methods, because sample sizes can be smaller in some instances.

Paired-comparison testing, however, is limited in value for a serious, ongoing product-testing program. The paired-comparison test does not tell us when both products are bad and does not lend itself to the use of normative data. It is heavily influenced by the “interaction effect” (i.e., any variations in the control product will create corresponding variance in the test product's scores).

Repeated Pairs Test

A repeated paired-comparison taste test is exactly what the name suggests. Each respondent participates in a paired-comparison taste test (e.g., product J versus product H), followed by a second paired-comparison test (product J versus product H). However, in the second test, the products are presented as two different products (i.e., not labeled as products J and H).

The purpose of the repeated paired-comparison taste test is to identify nondiscriminators, the people who don't choose the same product in both tests. That is, it is assumed that someone who chooses product J in the first paired-comparison test and chooses product H in the second paired-comparison test cannot taste (or detect) any difference between the two products. Typically, these nondiscriminators' answers would not be counted. The final results would be based only on respondents who could discriminate between the two products (i.e., based only on those who chose the same product both times).

Triangle Test

The triangle taste test is used primarily for “difference testing.” Each participant is presented with three products and asked to taste all three and choose the one that is different from the other two. The triangle taste test is used to determine who can discriminate (i.e., consistently identify the one product that's different) and who cannot.

These discriminators are, in turn, used as members of small expert panels (sometimes called sensory panels) to assist research and development in formulating and reformulating products, using the triangle design to determine if a particular ingredient change, or a change in processing, creates a detectable difference in the final product. Triangle taste testing is also used in quality control to determine if a particular production run (or production from different factories) meets the quality-control standard (i.e., is not different from the product standard in a triangle taste test using discriminators).

Custom Product Testing Services

Decision Analyst is a recognized leader in consumer product testing and optimization. Its staff has evaluated more than 1,000 foods, beverages, and other products during the past four decades. The firm has many staff members with extensive experience in the conduct and analysis of product testing and optimization studies. The company is a leader in the development of analytical techniques to enhance product testing and optimization.

If you would like more information on product testing, please contact Bonnie Janzen, President, by email at, or Jerry W. Thomas, Chief Executive Officer, by email at Both can be reached by calling 1-800-ANALYSIS (262-5974) or 1-817-640-6166.