Alexandria, VA, USA – A study evaluating the impact of the Soft Drinks Industry Levy (SDIL) on socioeconomic inequalities in hospital admissions for caries-related extractions in England was presented at the 104th General Session of the IADR, which was held in conjunction with the 55th Annual Meeting of the American Association for Dental, Oral, and Craniofacial Research and the 50th Annual Meeting of the Canadian Association for Dental Research on March 25-28, 2026 in San Diego, CA, USA.
Investigators used monthly data on hospital admissions in NHS hospitals in England, between March 2007 and December 2024 for 0-17-year-olds. Admission rates were calculated per 100,000 person-months by dividing the monthly number of hospital admissions by the mid-year population aged 0-17 years and multiplying the result by 100,000. Admission rates for tonsillectomy were chosen as a negative control outcome. Admission rates were stratified by quintiles of the 2019 Index of Multiple Deprivation quintiles at lower super output areas level.
The slope and relative indices of inequality (SII and RII) were used to evaluate the magnitude of the absolute and relative inequalities in admission rates by area deprivation. To assess the SDIL impact, the observed rates were compared against a counterfactual scenario, i.e. the predicted trend had the pre-announcement data (April 2007-February 2016) continued without intervention. A segmented regression model was fitted with a parameterization that incorporated four key policy and contextual phases (SDIL announcement, implementation, COVID-19 lockdown, and post-lockdown recovery). When comparing the counterfactual and observed trends, there were absolute reductions in the SII for caries-related extractions of 3.89 (95%CI: 1.21, 6.56) and 9.27 (95%CI: 5.20, 13.35) 22 and 80 months after implementation, corresponding to relative reductions of 9.16% (95%CI: 3.18, 15.13) and 25.54% (95%CI: 15.74, 35.34), respectively. There were also absolute reductions in the RII of 0.03 (95%CI: 0.01, 0.05) at both 22 and 80 months after implementation, corresponding to relative reductions of 13.52% (95%CI: 4.56, 22.48) and 12.74% (95%CI: 4.49, 20.99), respectively.
The abstract, “The UK Soft Drink Industry Levy and Socioeconomic Inequalities in Admission Rates for Caries-related Extractions” was presented by Eduardo Bernabé of Queen Mary University of London, UK during the “"Broken Smiles": What Oral Health Tells About Society” Oral Session that took place on Wednesday, March 25, 2026 at 1:30 p.m. PDT (UTC-7).
About IADR/AADOCR
The International Association for Dental, Oral, and Craniofacial Research (IADR) is a nonprofit organization with a mission to drive dental, oral, and craniofacial research for health and well-being worldwide. IADR represents the individual scientists, clinician-scientists, dental professionals, and students based in academic, government, non-profit, and private-sector institutions who share our mission. The American Association for Dental, Oral, and Craniofacial Research (AADOCR) is the largest division of IADR. Learn more at www.iadr.org.
