Clinical trial NCT02744859: Do Warning Labels Decrease Soda Purchasing?
Official title: Do Warning Labels Decrease Soda Purchasing?
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Healthy
Keywords: Decision Making
Consumption
Economics
Lead sponsor: Harvard University
Sponsor class: OTHER
First posted: 2016-04-20
Enrollment: 6000
Sex: ALL
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: TREATMENT

Brief summary: Investigators will run a field study evaluating the impact different labels have on the purchasing of sugar sweetened beverages. This field study will take place in a hospital cafeteria.

Detailed description: In a hospital cafeteria investigators will label all sugar sweetened beverages to evaluate their impact on purchasing.

Investigators will collect baseline data for two weeks on beverage sales at the hospital cafe. Following this data collection investigators will introduce a calorie label which reads "Each beverage contains \[lower calorie bound\]-\[upper calorie bound\] calories per container. 2,000 calories a day is used for general nutrition advice but calorie needs vary." These signs will be posted for two weeks and investigators will collect sales data. Following this intervention investigators will remove the signs and collect sales data for two weeks. At the end of this no label period, investigators will introduce the second intervention, a warning label. This label will read "WARNING: Drinking beverages with added sugar(s) contributes to obesity, diabetes, and tooth decay." This label will also be posted for two weeks and investigators will collect sales data. Investigators will then remove these signs and collect sales data for two weeks. Finally, investigators will introduce the third intervention: a warning label with graphic labels. This label will read "WARNING: Drinking beverages with added sugar(s) contributes to obesity, diabetes and tooth decay." However this sign will also include a visual depiction of each health consequence. Investigators will collect sales data for this two week period. After this intervention investigators will collect sales data for an additional two weeks and then administer a brief survey to cafeteria customers to better understand their impressions of the labels.

Eligibility criteria: Inclusion Criteria:

* Customers of the hospital cafeteria.

Exclusion Criteria:

* None

Primary outcomes:
measure: Sweetened beverages purchased
timeFrame: 2 week condition blocks
Secondary outcomes:
measure: Unsweetened beverages purchased
timeFrame: 2 week condition blocks
measure: Beverage calories sold
timeFrame: 2 week condition blocks
measure: Changes in types of beverages purchased
timeFrame: 2 week condition blocks
Other outcomes:
Locations:
Study officials:
affiliation: Harvard University
name: Grant E Donnelly, MA
role: PRINCIPAL_INVESTIGATOR
affiliation: Harvard School of Public Health (HSPH)
name: Laura Y Zatz, MPH
role: PRINCIPAL_INVESTIGATOR
References:
citation: Donnelly GE, Zatz LY, Svirsky D, John LK. The Effect of Graphic Warnings on Sugary-Drink Purchasing. Psychol Sci. 2018 Aug;29(8):1321-1333. doi: 10.1177/0956797618766361. Epub 2018 Jun 18.