Climate Impact Label Design and Fast-Food Meal Selection

Johns Hopkins Bloomberg School of Public Health

Status: Completed

Conditions: Food Selection

Treatments: Behavioral: Traffic Light Labels; Behavioral: Warning High Climate Impact Labels; Behavioral: Climate Grade Labels; Behavioral: Control (QR) Labels; Behavioral: Numeric Carbon Footprint Labels

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT06678178

IRB00030419 (Other Identifier)

1R01DK139327-01 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

The primary objective of this study is to test the relative effects of climate-impact menu label designs on the healthfulness of consumers' fast-food meal choices. Participants will complete a hypothetical online meal ordering task using a survey which emulates the online menu of a burger restaurant chain. Participants will be randomized for exposure to menus featuring one of five labeling conditions. Secondary objectives include examining total greenhouse gas emissions per meal order and, through a post-order survey, perception of labels between the conditions.

Full description

This online randomized trial will test the relative effects of climate impact menu label designs on the healthfulness of consumers' fast-food meal choices and perceptions of menu items. The survey research firm CloudResearch will recruit a sample of 6,250 adults aged 18 years and older who speak English and reside in the United States.

Participants will complete a between-subjects online experiment in which the participants will be randomized to view a fast-food online ordering menu with one of five labeling schemes applied: (1) a QR code on all items (control); (2) a high climate impact warning label on high impact items; (3) traffic light labels on all items by level of impact; (4) climate grade labels on all items by level of impact; and (5) numeric carbon footprint labels on all items. All fast-food menus will include main items, sides, desserts, and drinks. Labels will only appear alongside main menu items and will be assigned using thresholds for greenhouse gas emissions set a priori in kilograms of carbon dioxide (CO2) equivalent per kilogram of food. Participants will be instructed to select up to 4 menu items for a hypothetical meal order. After completing the meal ordering task, participants will be prompted to answer questions about the perception of the labeling condition which the participants were randomized to view, perception of the relative effectiveness of all labels in this experiment, and personal values, dietary patterns, and other demographic information.

The primary outcome will be the healthfulness of meal orders selected from the online menu, indicated by a modified Nutrient Profile Index meal score for all food items ordered. Secondary outcomes will be total greenhouse gas emissions per meal ordered, total calories ordered, whether a sugar-sweetened beverage was ordered, and perceived message effectiveness of the climate-impact labels.

Enrollment: 6,622 patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• 18 years of age or older
• Member of the CloudResearch panel
• Residing in the United States

Exclusion criteria

• Under 18 years of age
• Not residing in the United States
• Completed the survey implausibly quick based on the distribution of the time to complete the survey among all participants
• Failed the built-in Qualtrics survey fraud detection measures

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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6,622 participants in 5 patient groups, including a placebo group

Control (QR) Labels

Placebo Comparator group

Description:

A black label featuring a QR code and white text that reads "SCAN HERE" will be placed beneath all main menu items. Explanatory text describing the label's meaning will be displayed at the top of the menu.

Treatment:

Behavioral: Control (QR) Labels

Warning High Climate Impact Labels

Experimental group

Description:

A red icon-plus-text label that reads "WARNING: HIGH CLIMATE IMPACT" in white text will be placed beneath main menu items with a high climate impact using a predetermined threshold of estimated greenhouse gas emissions set at \>=9.2 kgCO2e. Labels will include a white globe icon directly preceding the label text. Explanatory text describing the label's meaning will be displayed at the top of the menu.

Treatment:

Behavioral: Warning High Climate Impact Labels

Traffic Light Labels

Experimental group

Description:

Traffic Light labels will be placed beneath all main menu items. Using predetermined estimated greenhouse gas emission thresholds, each item will be assigned one of three icon-plus-text labels within this scheme: low-, medium-, or high-impact label, set in kgCO2e at \<2.6, \>=2.6 \& \<9.2, and \>=9.2, respectively. Each will read, "HIGH CLIMATE IMPACT" within a red label, "MED. CLIMATE IMPACT" in a yellow label, and "LOW CLIMATE IMPACT" in a green label. Text for all labels written in white, and a white globe icon will precede the text. Explanatory text describing the meaning of the labels will be displayed at the top of the menu.

Treatment:

Behavioral: Traffic Light Labels

Climate Grade Labels

Experimental group

Description:

Climate Grade labels will be placed beneath all main menu items, using predetermined estimated greenhouse gas emission thresholds to assign one of five icon-plus-text labels which indicate a specific climate impact grade (A, B, C, D, and F). Thresholds are set in kgCO2e as follows: \[A\] \<1.7, \[B\] \>=1.7 \& \<2.6, \[C\] \>=2.6 \& \<9.2, \[D\] \>=9.2 \& \<28, \[F\] \>=28. All labels are solid black with a white globe icon followed by white text which reads "CLIMATE GRADE". On the left side of each label, a grade is displayed, capitalized and in a white font within a solid-colored box. The color of the box corresponds with each letter grade: A = dark green, B = light green, C = yellow, D = orange, F = red. Beneath the letter grade, a gradient of all possible grades is displayed horizontally in smaller font, each grade atop a small solid box in the respective grade color. Explanatory text describing the meaning of the labels will be displayed at the top of the menu.

Treatment:

Behavioral: Climate Grade Labels

Numeric Carbon Footprint Labels

Experimental group

Description:

Numeric Carbon Footprint labels will be placed beneath all main menu items and display the estimated greenhouse gas emissions in kilograms of carbon dioxide equivalents (kgCO2e) for each item. All labels have a solid black background and an icon-plus-text design. A white globe icon is followed by text stating the value of the items estimated emissions and the unit "kgCO2e". Explanatory text describing the meaning of the labels will be displayed at the top of the menu.

Treatment:

Behavioral: Numeric Carbon Footprint Labels