How should importance of naturalness be measured? A comparison of different scales

Naturalness is an important heuristic method for examining consumers' evaluation and choice of food. In recent years, several scales have been proposed to measure the importance of naturalness for consumers. These scales vary in the number of items they contain and in the aspects they cover. The aim of our research was to examine how strongly the different scales are correlated, whether they differ in their predictive validity, and which scale should be recommended for the assessment of the importance of naturalness for consumers in future studies. Because existing scales incorporated items that are also used for the validation of the scale and many scales only consider a restricted number of different aspect on naturalness, we constructed a new naturalness scale that covers the production process and the ingredients. To compare the scales, we conducted an online survey (n = 632) with participants from Germany. The results showed that the various scales are highly intercorrelated. All scales were good predictors of the purchase frequency of organic foods, perceived willingness to eat in-vitro meat and perceived naturalness of in-vitro meat but our new scale was not particularly better than the others. We conclude that the scales can be used interchangeably and we recommend using the shortest, and therefore, most efficient measure for the importance of naturalness. The results illuminate a general problem, new scales have been introduced without demonstrating that they measure something different than the existing scales.