Socioeconomic position and the effect of price interventions on healthier and less healthy food on food selection in a simulated food delivery app: a randomised controlled trial.

OBJECTIVE

We examined the effects of price interventions on the healthiness of a hypothetical food order in a simulated online out-of-home food delivery app.

DESIGN

The design was a randomised controlled trial, with four conditions (10 % taxation of less healthy menu items; 10 % subsidy of healthier menu items; a combination of taxation and subsidy; standard pricing), and recruitment was stratified by socioeconomic position (SEP). Primary outcomes were healthier v. less healthy main meal selected and total kilocalories (kcals) selected.

SETTING

Participants selected a hypothetical evening meal from out-of-home food outlets on a simulated online food delivery app.

PARTICIPANTS

N 3106 adult participants from the UK were randomised into taxation (n 750), subsidies (n 808), a combination of taxation and subsidies (n 769), and standard pricing (n 779). 57-58 % of participants were iof higher SEP.

RESULTS

There were no statistically significant effects of the pricing interventions on whether a healthy v. less healthy main meal was selected (e.g. taxation v. control OR 0·91 (95 % CI 0·74, 1·12); subsidies v. control OR 1·08 (95 % CI 0·89, 1·31)) or on total kcals selected (e.g. taxation v. control regression coefficient -44·31 (95 % CI -95·90, 7·28); subsidies v. control regression coefficient -7·94 (95 % CI -60·23, 44·35)). There was no evidence that effects differed by SEP.

CONCLUSIONS

We found no convincing evidence that 10 % changes in price of healthy and less healthy food in a simulated out-of-home food delivery app significantly impacted on healthiness of food selected. Further research may benefit from examining effects of larger price changes and in real-world purchasing conditions.