There is substantial global evidence that interpretive front-of-pack (FOP) nutrition labels are better understood than non-interpretive numerical labels. However, robust evidence on the effects of interpretive labels on consumer food purchases in the real-world is lacking.
To assess the effects of two interpretive FOP nutrition labels, compared with a standard non-interpretive numerical label, on the healthiness of consumer food purchases.
A five-week (one week baseline and four weeks intervention), three-arm New Zealand-wide parallel randomised controlled trial commenced in August 2014. 1500 adult smartphone owners who regularly shop in a supermarket will be randomised in a 1:1:1 ratio to: 1) Traffic-light labels; 2) Health Star Rating labels; or 3) Nutrition Information Panel (control). Randomisation will be stratified by ethnicity and self-reported interest in healthy eating. All stages of the trial will be conducted remotely, online (screening) or via a bespoke smartphone application (questionnaires, randomisation, delivery of the intervention, data collection). Participants will view their allocated nutrition label via the application by scan the barcode of packaged food products using their smartphone camera. The allocated label instantly appears on the smartphone screen. Participants record all food and beverage purchases made throughout the study using the app (scanning product barcodes; photographing till receipts). The primary study outcome will be healthiness of all food purchases over the intervention period measured using mean Food Standards Australia New Zealand nutrient profiling score (difference between FOP label intervention and control arms). A number of secondary outcomes will also be evaluated.
This large, randomised, controlled trial will provide robust evidence of the effectiveness and potential cost-effectiveness of FOP labelling as means to improve population diets and healthTrial registration Australian New Zealand Clinical Trials Registry (ACTRN12614000644662)