Different From Control
Introduction
The difference-from-control test is used to quantify differences between a tested sample and a control sample. This method is particularly applicable when comparing products with a single sensory attribute or only a few varying sensory attributes.
The test can be conducted in several ways: one method involves assessing the overall degree of difference using a single intensity category scale, while another method involves evaluating the differences in key attributes compared to the control standard using a bipolar scale with a central point corresponding to the control standard.
The latter method allows for the evaluation of both the extent and direction of differences in sensory attributes. A predetermined level of unacceptable quality or rejection should be established in advance. Panellists participating in the test should possess knowledge of acceptable, unacceptable, and rejectable ranges for products.
Template Description
The template includes an initial screen, which can be used to provide instructions to the panellists. Subsequently, the panellists will be presented with one product. Their task is to assess the product and indicate the extent of dissimilarity between the test product and the control product previously provided as a reference.
In the design section, three alternative scales are presented for selection:
- A 10-point "Difference From Control" scale with anchors ranging from "No difference" to "Extreme difference."
- A 5-point "Difference From Control" scale with anchors spanning from "No difference" to "Extreme difference."
- A 7-point "Bi-Polar Difference From Control" scale.
The end screen of the template features a thank-you message, offering the opportunity to customize a final message for panellists.
Within the design settings, there is an option to review how each panellist will receive the sample. Each set corresponds to a specific order of presentation, with panelists receiving the samples in a monadic sequential order, one product after another.
It's worth noting that in this template, product 1 is designated as the reference product, and product 2 is identified as the new formulation. However, additional products can be incorporated, and the reference product does not necessarily have to be product 1. If a custom autoreport is used, it is often mandatory that P01 is the reference product.
Raw Data Representation
The raw data will be presented, where each row aligns with an individual judge and the evaluated sample. The data will be stored to reflect the intensity value chosen by the panelists, in accordance with the predefined value in the utilized question type. The data will be stored to reflect the intensity value chosen by the panelists, based on the predefined value in the utilized question type.
Analysis
Once data has been gathered, you can access EyeOpenR and navigate to the Discrimination methods. Choose the Different From Control analysis to examine your results. Additional details about this analysis can be found in the following article: https://support.eyequestion.nl/portal/en/kb/articles/a-not-a-analysis
References
- Lawless, H. T., & Heymann, H. (2010)
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