Correction to SDIL analysis in BMJ by Pell et al (2021)
In December 2023 we were made aware of changes to a paper that we have referenced in our work, analysing changes in the purchasing of sugar in soft drinks after the introduction of the Soft Drinks Industry Levy.
Following publication of this study, subsequent analysis by the research team identified that the analysis presented in the original paper contained an error. The authors alerted the BMJ, who have now retracted the original paper and published a corrected version in BMJOpen.
Overall, the estimate of change in purchasing of sugar from all soft drinks combined at one year post implementation of the levy reduces from a 30g (or 10%) fall per household per week to an 8g (or 3%) fall per household per week. Alongside this, the estimate of change in volume of soft drinks purchases increases from no change to a 189g (or 3%) increase per household per week.
Since being made aware of this we have updated our reports and briefings to include the corrected figures and we are informing our partners to ensure they do the same.
Despite the correction, the authors believe that the results still have important public health implications and indicate that the UK Soft Drinks Industry Levy may have had a public health benefit by reducing household purchasing of sugar from soft drinks, despite the slight increase in overall sales volume of soft drinks that were purchased.
All other data that we have referenced in our publications remain accurate, including figures published by the Office for Health Improvement and Disparities which has shown there was a 34.3% reduction in total sugar sales from soft drinks between 2015 and 2020 (removing 46,000 tonnes of sugar from our diets).
We can also confirm that modelling on the potential health and economic impact of further levies, undertaken for the Recipe for Change campaign by the London School of Hygiene and Tropical Medicine, did not draw on calculations from the 2021 Pell et al paper and so also remains unchanged, indicating the increased impact we could have if we expand levies beyond soft drinks alone.