Protocol analysis was subsequently carried out. ATLAS.ti soft- ware was used to deal with the content emphasis of the focus group interview data input, and complete the interpretation of the conceptual framework. Three types of coding based on the grounded theory were used: open, axial, and selective. Open cod- ing is a process that defines the concept and property of data for analysis. It can be used in conceptual categorization and induction. A gradual transformation of data was conducted for the next step, axial coding, which deals with correlative categories and sub-cate- gories. Finally, selective coding involves a process of integrating and refining to construct a scientific theory needed to interpret the differentiation in package designs [66]. Regression analysis was then conducted to obtain the displayability formula by prov- ing package differentiation has an influence on the number of clas- ses in distinguishing packaging.