Experiences with the reliability and Validity of the Kano-Method: Comparison to Alternate Forms of Classification of Product Requirements
Dr. Elmar Sauerwein
Department of Management/University of Innsbruck
Tel. ++43/512/507-7188 or +43/664/3357775
Reliability and validity of the Kano-Model have not yet been tested thouroughly. This paper tries to examine the reliability of test-retest, alternate forms and stability of interpretation. Furthermore concurrent, predictive and convergent validity were tested. Other methods of classification were tested, too.The results are supportive for the Kano model.
Introduction: Kano’s model of customer satisfaction
In his model, Kano  distinguishes between three types of product requirements which influence customer satisfaction in different ways when met:
Must-be requirements: If these requirements are not fulfilled, the customer will be extremely dissatisfied. On the other hand, as the customer takes these requirements for granted, their fulfillment will not increase his satisfaction. The must-be requirements are basic criteria of a product. Fulfilling the must-be requirements will only lead to a state of "not dissatisfied". One-dimensional requirements: With regard to these requirements, customer satisfaction is proportional to the level of fulfillment - the higher the level of fulfillment, the higher the customer’s satisfaction and vice versa. Attractive requirements: These requirements are the product criteria which have the greatest influence on how satisfied a customer will be with a given product. Attractive requirements are neither explicitly expressed nor expected by the customer. Fulfilling these requirements leads to more than proportional satisfaction. If they are not met, however, there is no feeling of dissatisfaction. [pic]
Figure 1: Kano’s model of customer satisfaction [Berger, 1993]
For each product feature a pair of questions is formulated to which the customer can answer in one of five different ways [Kano, 1984]. The first question concerns the reaction of the customer if the product has that feature (functional form of the question), the second concerns his reaction if the product does not have that feature (dysfunctional form of the question).
Figure 2: Functional and dysfunctional question in the Kano questionnaire
By combining the two answers in the following evaluation table, the product features can be classified [Sauerwein et.al. 1996]:
Figure 3: Kano evaluation table
If the customer answers, for example, "I like it that way," as regards "If the edges of your skis grip well on hard snow, how do you feel?" - the functional form of the question, and answers "I am neutral," or "I can live with it that way," as regards "If the edges of your skis don’t grip well on hard snow, how do you feel?" - the dysfunctional form of the question, the combination of the questions in the evaluation table produces category A, indicating that edge grip is an attractive customer requirement from the customer’s viewpoint. If combining the answers yields category I, this means that the customer is indifferent to this product feature. He does not care whether it is present or not. He is, however, not willing to spend more on this feature. Category Q stands for questionable result. Normally, the answers do not fall into this category. Questionable scores signify that the question was phrased incorrectly, or that the person interviewed misunderstood the question or crossed out a wrong answer by mistake. If looking up the answer in the evaluation table yields category R, this product feature is not only not wanted by the customer but he even expects the reverse. For instance, when offering holiday tours it might well be that a specific customer segment wants pre-planned events every day, while...
Please join StudyMode to read the full document