Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT05007184 |
| Other study ID # |
7197919 |
| Secondary ID |
|
| Status |
Completed |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
July 7, 2021 |
| Est. completion date |
July 26, 2021 |
Study information
| Verified date |
August 2021 |
| Source |
Duke-NUS Graduate Medical School |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
Using a 3-arm randomized controlled trial, the investigators aim to rigorously evaluate the
effects of two front-of-pack (FOP) food labels on diet quality. The first food label is a
modified version of Chilean warning FOP label and the second food label is a modified version
of French FOP label, Nutri-Score. The investigators used an experimental online grocery
store, called NUSMart, which is similar in design to commercial web-based grocery stores to
test these two FOP labels. Participants were randomly assigned to one of the following arms
and asked to complete a one-time hypothetical shop.
Arm 1: Participants experienced a default version of NUSMart which replicated the traditional
shopping experience of online grocery stores with no FOP labels (Control).
Arm 2: Same as Arm 1 NUSMart except that Chilean warning FOP labels were displayed on less
healthy food and beverages. Products with specific nutrients (i.e. sugar, sodium, saturated
fat, energy) falling outside the bounds of the thresholds defined by the Chilean warning
labels were depicted with the warning labels on them.
Arm 3: Same as Arm 1 NUSMart except that Nutri-Score FOP labels along with % sugar per
serving were displayed on all food and beverages. These labels score products on the basis of
7 nutrients (calories, saturated fats, sugar, salt, fibre, protein and percentage of fruits,
vegetables and nuts) from A to E (best to worst). To ensure that participants understood what
Nutri-Score labels mean and how they work, an introductory video was shown before shopping.
The investigators hypothesize the following:
Hypothesis 1: Diet quality, as measured by weighted average Nutri-Score point of shoppers'
final baskets, will be greatest in Arm 3, followed by Arm 2, followed by Control.
Hypothesis 2: Grams of sugar per serving/ milligrams of sodium per serving/ grams of
saturated fat per serving/ calories per serving will be least in Arm 2, followed by Arm 3,
followed by Control.
Description:
Experimental design & procedures
The aim of this study is to use a 3-arm randomized controlled trial with an online grocery
store (NUSMart), to rigorously evaluate the effect of the two FOP labels, Chilean warning
labels and Nutri-Score, on diet quality.
1. Food labels
The investigators tested 2 different types of food labels in this study. They are as
follows:
1. Chilean Warning Labels: These labels were implemented in Chile in 2016. They are
shown on those less-healthy food and beverage products that don't fall within
thresholds that are defined for the following nutrients: sugar, sodium, calories
and saturated fats. The original labels are in Spanish but the ones that the
investigators displayed were in Arabic.
2. Nutri-Score Labels: These labels were implemented by the French government in 2017.
They are shown on all food and beverage products and range from A to E with the
corresponding colours moving from Green to Red (symbolizing best to worst). The
scores and grades are calculated based on 7 different nutrients grouped into 2
categories i.e. nutrients to consume (such as fibre) and nutrients to avoid (such
as sugar). The investigators modified the labels by adding % sugar per serving on
the right side of the labels.
2. Overview of RCT Design
To test these labels, the investigators used three different versions of NUSMart. Each
participant was randomly assigned to one of the following arms and asked to complete a
one-time hypothetical shop.
Arm 1: Control arm. Participants experienced an unmodified version of NUSMart, which
replicates the traditional shopping experience of online grocery stores.
Arm 2: Similar to Arm 1 except that products were labeled with Chilean warning FOP
labels.
Arm 3: Similar to Arm 1 except that products were labeled with NutriScore FOP labels.
To minimize hypothetical shopping biases, the investigators set a minimum spending value
per person per week and adjusted the total minimum spending value depending on household
size.
3. Subject related procedures
As the investigators have done in prior studies, participants were recruited if they were KSA
residents aged 18 years or older, could speak Arabic and were primary weekly shoppers for
their households. Recruitment was done using a Saudi Arabia based web panelist.
On recruitment, they were asked to fill in a baseline questionnaire to collect demographic
and health characteristics, which took approximately 10-15 minutes to complete.
The baseline questionnaire includes a question as to whether any household members have a
medical condition, such as diabetes or hypertension, which requires limiting the types of
foods they eat. The investigators asked this question to allow for testing whether the
interventions differentially influence these households, with the expectation that households
with less healthy patients may obtain greater benefits from purchasing baskets with higher
mean Nutri-Scores. Since the objective of this RCT is to quantify the effectiveness of the
interventions on diet quality, a precursor to NCDs, the collection of household health
indicators is reasonable.
Upon completion of the baseline survey, participants were randomly assigned to one of the 3
shopping conditions (Arm 1 [Control], Arm 2, or Arm 3). They logged into the NUSMart website
and were asked to purchase their weekly groceries with a minimum spend per person per week
(the total minimum spending value depends on the household size). Each participant therefore
shopped only once during the study in one of the arms (1,2 or 3) which was randomly assigned
to them.
Participants were given explicit instructions to purchase groceries for the purposes of
breakfast, lunch, dinner, snacks and beverage consumption for one week keeping in mind that
they would not be consuming any meals outside. The stores were set up such that participants
were not allowed to check out with their cart unless they selected items from at least 4
different NUSMart categories. This ensures that participants shop as though they are shopping
for their own consumption i.e. to minimize hypothetical biases.
A post-study survey was conducted after the last shop to collect participant opinions on the
labels and understand their impact better.
