Clinical trial NCT02926001: Evaluation of the Impact of a Sugar-Sweetened Beverage Tax in Chile
Official title: Empirical Evaluation of the Short Term Impact of a Sugar-Sweetened Beverage Tax in Chile
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Chronic Disease
Obesity
Keywords: Taxes
Beverages/economics
Carbonated Beverages/economics
Diet, Food and Nutrition/economics
Economics
Energy Intake
Risk Factors
Lead sponsor: University of York
Sponsor class: OTHER
Collaborators: name: University of Chile
First posted: 2016-10-06
Enrollment: 2836
Sex: ALL
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Time perspective: RETROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: The study population is 2,836 households that arenationally representative of urban areas in Chile.

Brief summary: The purpose of this study is to evaluate formally the short term impacts of the tax policy applied to Sugar-Sweetened Beverages (SSBs) in Chile. The Impuesto Adicional a las Bebidas Analcohólicas (IABA, or "additional tax on soft drinks") in Chile was enacted in October 2014, affecting any non-alcoholic beverages to which colorants, flavourings or sweeteners have been added. For beverages above an added sugar concentration of at least 6.25 grams per 100ml (or equivalent proportion), the tax was increased from 13% to 18%, while for those below this threshold the tax was decreased to 10%, producing an 8% tax difference between these beverage groups. This impact evaluation analysis of the Chilean sugar-sweetened beverage (SSB) tax will estimate the impact of increasing the tax as well as decreasing the tax on soft drinks. The study will use household level grocery purchasing data for Chile. The purchasing records are available from October 2011 to September 2015 (three years before; and one year after the implementation of the tax in October 2014). The investigators will use a series of quasi-experimental approaches to evaluate the causal impact of the SSB tax policy on consumers' behaviour as well as on industry responses in the form of pricing and price promotion decisions.


Eligibility criteria: Inclusion Criteria:

* Household in Chile that agreed to participate in the purchasing survey and provided data to a satisfactory degree for the first 2 months.

Exclusion Criteria:

* Households that are unwilling to participate in the survey. Households that change physical address. Households with poor compliance to the survey.

Primary outcomes:
measure: Volume of sugar-sweetened beverage purchased
timeFrame: October 2011 - September 2015
Secondary outcomes:
measure: Consumer shopping patterns - Frequency
timeFrame: October 2011 - September 2015
measure: Consumer shopping patterns - Volume
timeFrame: October 2011 - September 2015
measure: Market price of sugar-sweetened beverages
timeFrame: October 2011 - September 2015
measure: Body mass index of household members
timeFrame: October 2011 - September 2015
Other outcomes:
Locations:
Study officials:
affiliation: Centre for Health Economics, University of York
name: Marc Suhrcke, PhD
role: PRINCIPAL_INVESTIGATOR
affiliation: Centre for Health Economics, University of York
name: Ryota Nakamura, PhD
role: PRINCIPAL_INVESTIGATOR
affiliation: Centre for Health Economics, University of York
name: Andrew J Mirelman, PhD
role: PRINCIPAL_INVESTIGATOR
affiliation: University of Chile
name: Cristobal Cuadrado, MD, PhD
role: PRINCIPAL_INVESTIGATOR
affiliation: University of Chile
name: Nicolas Silva, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Nakamura R, Mirelman AJ, Cuadrado C, Silva-Illanes N, Dunstan J, Suhrcke M. Evaluating the 2014 sugar-sweetened beverage tax in Chile: An observational study in urban areas. PLoS Med. 2018 Jul 3;15(7):e1002596. doi: 10.1371/journal.pmed.1002596. eCollection 2018 Jul.