Moskowitz, H.R. (2008) Chapter 14: Sample Size N, or Number of Respondents in Viewpoints and Controversies in Sensory Science and Consumer Product Testing. In: Moskowitz, H.R., Muñoz, A.M. and Gacula, M.C., Eds., Viewpoints and Controversies in Sensory Science and Consumer Product Testing, John Wiley & Sons, Trumbull, 241-254.

has been cited by the following article:

• TITLE: Consumer Panel Size in Sensory Cosmetic Product Evaluation: A Pilot Study from a Statistical Point of View

  AUTHORS: Jürgen Blaak, Daniela Keller, Isabel Simon, Marina Schleißinger, Nanna Y. Schürer, Peter Staib

  KEYWORDS: Claim Substantiation, Consumer Panel Size, Product Evaluation, Sample Size Calculation

  JOURNAL NAME: Journal of Cosmetics, Dermatological Sciences and Applications, Vol.8 No.3, August 31, 2018

  ABSTRACT: Subjective evaluations are nowadays applied more commonly in cosmetic product assessment. They are used in quality control, product development steps and efficacy studies for claim support. Several studies have been published to determine the adequate number of panelists, but recommendations and guidelines dealing with this topic are rare in the cosmetic sector. The aim of the present pilot study was to recommend a suitable study plan and define the adequate consumer panel size for cosmetic consumer assessment. A questionnaire-based product evaluation study, with three different cosmetic products, was organized as a consumer test using a seven-point scale. As a last step, a specific statistical calculation was performed to define the minimum sample size. It showed that the minimum sample size, besides the obvious statistical parameters of standard deviation and confidence interval, also depends on age and gender of the panelists and product assessment item. Utilizing a CI of 95% a minimum of 60 panelists seems to be sufficient for home-use-test (HUT) with a given seven-point scale. A minimum of 101 panelists are shown to be sufficient utilizing a CI of 99%.