The impact of energy or traffic light labelling on parent and child fast food selection

The study protocol required participants to complete two scripted telephone surveys conducted by a trained research assistant. A baseline survey conducted during June and July 2011 collected demographic and health behaviour data from parents and a child aged three to 12 years in their household. Where parents had more than one child from age three to 12, the child with the most recent birthday was selected. Following completion of the baseline survey, participants were randomly allocated to one of three groups using a random number function embedded in the computer assisted telephone interviewing software in a 1:1:1 ratio without stratification. Based on group allocation, participants in this study were posted one of three hypothetical fast food menus. Menus were comprised of items selected from a variety of common fast food outlets in Australia. Generic descriptive names were provided for each food item to reduce any pre-conceived beliefs about existing branded fast food products. Groups were as follows Group 1. Standard fast food menu (control). All items in this menu were included in subsequent menus. The standard menu contained 36 food and beverage items, including healthier options. Group 2. Standard menu with energy labelling. This menu was identical to that provided to Group 1, with the addition of energy content information being displayed next to each menu item. Energy content was displayed in kilojoules (kJ). Group 3. Standard menu with traffic light (sign-post) labelling. The menu items were identical to that provided to Groups 1 and 2, with the addition of a single coloured symbol (traffic light) placed next to each menu item. The single coloured symbol of red, amber, or green reflected the saturated fat, sugar, salt and energy content of each menu product adapted from criteria developed for school canteens in Australia Energy content, volume measures and pricing were sourced from the Australian websites of fast food outlets from which the menu items had been sourced. Participants answered a series of questions about these menus in the follow up survey, which was conducted on average 17 days after the completion of the baseline survey. The follow up interview contained questions about purchase intentions, awareness of labelling information and attitudes towards fast foods.