How do peanut and nut-allergic consumers use information on the packaging to avoid allergens?

BACKGROUND: Recent legislation has sought to improve the information printed on packaged foods relevant to the safety of food allergic consumers. We aimed to understand the complex risk assessment decisions made by peanut and nut-allergic adults when purchasing food, with particular reference to use of printed package information.
METHODS: The behaviour and 'thinking aloud' of 32 participants were recorded during their normal food shop, followed by a semi-structured interview. During the interview they were given 13 potentially problematic packaged foods, and asked if they would purchase the product and what their reasons were. Transcribed data from the shop, interview and 13-product task were analysed to explore use of allergy advice boxes, ingredients lists and other packaging information.
RESULTS: Some participants used the ingredients list as their primary check for allergens, but most used the allergy advice box. Package-based information was generally considered reliable, but some supermarket and brand labels were trusted more than others. Images and product names were used to draw inferences about the presence of nuts. A number of improvements were suggested by participants, particularly a request for more 'nut free' labelling.
CONCLUSIONS: Food labels were used in conjunction with nonpacket-based strategies (e.g. previous experience) to make choices. External factors (e.g. trust of manufacturer) informed interpretation of and confidence in labels. Images and product names, not intended by manufacturers as an allergen risk assessment aid, were also used to inform choices.