Table 1

Outcomes, survey questions and responses

Outcome	Survey question	Response
Intention to purchase the least harmful option or none of the options	Please imagine that you are in the supermarket purchasing food. You want to purchase several products. You will see sets of packages and you will be asked to indicate the one you would purchase. You can also indicate that you would not select any of the available products. (The respondents were shown four sets of three products, and for each set they were asked the following question) Which product would you buy?	Number of times the respondent chose the least harmful option or none of the options (zero to four times).
Correct identification of the least harmful option	Please imagine that you are still in the supermarket purchasing food. This time you want to select the least harmful product in different categories. You will see sets of packages and you will be asked to indicate the product least harmful to health. (The respondents were shown four sets of three products, and for each set they were asked the following question) Which is the product least harmful to health?	Number of times the respondent selected the least harmful option correctly (zero to four times).
Correct understanding about the nutritional content of products	Please imagine that you are still in the supermarket purchasing food. You have selected a product and you want to decide whether the content of any nutrient is higher than recommended for a healthy diet. You will see a series of packages and you will be asked to indicate whether the content of any of the listed nutrients is higher than recommended for a healthy diet. (The respondents were shown four products from different categories, one by one and for each product they were asked the following question). Is the content of any of the following nutrients in this product higher than recommended for a healthy diet? You can select all the options that apply. I will read the options to you. Sugar is higher than recommended for a healthy diet. Sodium is higher than recommended for a healthy diet. Total fat/fat is higher than recommended for a healthy diet. Saturated fat is higher than recommended for a healthy diet. Trans fat is higher than recommended for a healthy diet. None of the nutrients is higher than recommended for a healthy diet.	Number of times the respondent answered correctly about the nutritional content of products (zero to four times).