Clinical Trial Details
— Status: Not yet recruiting
Administrative data
| NCT number |
NCT06440421 |
| Other study ID # |
#0002004615 |
| Secondary ID |
|
| Status |
Not yet recruiting |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
July 2024 |
| Est. completion date |
December 2024 |
Study information
| Verified date |
June 2024 |
| Source |
Duke-NUS Graduate Medical School |
| Contact |
Michelle TN Chow, BSc |
| Phone |
+65 6516 1276 |
| Email |
michelle.chow[@]duke-nus.edu.sg |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
Using a two-arm randomized controlled trial (RCT) and an intercept survey, the investigators
aim to evaluate the effects of the Multiple-Traffic Light (MTL) front-of-pack (FOP) food
labels in Bahrain, on diet quality of grocery shoppers in the Kingdom of Bahrain. The
investigators will use an experimental online grocery store, called Bahrain e-Mart, which is
similar in design to commercial web-based grocery stores to test these labels. Participants
will complete an online shopping experiment on Bahrain e-Mart such that those assigned to the
control arm and those assigned to the intervention arm would be exposed to food and beverage
products with no FOP labels and with MTL labels, respectively.
Participants will randomly be assigned to one of the following arms and asked to complete a
one-time shop.
Arm 1 (Control): Participants will experience a default version of Bahrain e-Mart which
replicates the traditional shopping experience of online grocery stores with no FOP labels.
Arm 2 (MTL): Same as Arm 1 Bahrain e-Mart except that Multiple-Traffic Light (MTL) labels are
displayed on all food and beverage products.
The investigators hypothesize the following:
Hypothesis 1: Diet quality, as measured by weighted (by the number of servings) average of
all purchased products' Multiple Traffic Light scores for the shopping trip, will be greater
in Arm 2 as compared to Control. Multiple Traffic Light is a nutrition labelling system
wherein each nutrient attribute constituting this label is assigned different colours
according to whether the amount of that nutrient is low (green), medium (amber) or high
(red).
Hypothesis 2: Diet quality, as measured by weighted (by the number of servings) average of
all purchased products' Nutri-Score points for the shopping trip, will be greater in Arm 2 as
compared to Control. Relying on the British Food Standard Agency Nutrient Profiling System,
the Nutri-Score (NS) point system assigns points to each product based on levels of 7
nutrients (calories, saturated fats, sugar, salt, fibre, protein and percentage of fruits,
vegetables, and nuts) per 100g or 100 ml to assess overall nutritional quality. The final NS
points range from 0 to 55, with 0 being the least healthy score and 55 the healthiest.
Hypothesis 3: The weighted (by the number of servings) average calories (kcal), sugar (g),
sodium (mg), total fat (g), and saturated fat (g) per serving will be less in Arm 2 as
compared to Control.
Description:
Experimental design & procedures
The aim of this study is to use a 2-arm randomized controlled trial with an online grocery
store (Bahrain e-Mart), to rigorously evaluate the effect of the Multiple Traffic Light
front-of-pack (MTL FOP) labels displayed on all food and beverage products, on diet quality.
Multiple Traffic Light (MTL) Labels
The investigators will test one type of front-of-pack (FOP) label known as MTL. The MTL label
includes per serving size information and grades each nutrient i.e., energy, sugar, fat,
saturated fat, and sodium separately based on recommended thresholds. Green signifies a
healthy amount of that nutrient; red signifies an unhealthy amount, and amber signifies that
the nutrient levels fall between healthy and unhealthy amounts. Additionally, the label also
shows how much of a person's daily allowance for a particular nutrient is met by consuming
one serving of the product. Lastly, MTL includes the absolute values of each nutrient per
serving of a product and the percentage of an adult's daily reference intake that is met by
consuming a serving of this product.
Overview of Randomised Control Trial (RCT) Design
To test these labels, the investigators used two different versions of Bahrain e-Mart. Each
participant was randomly assigned to one of the following arms and asked to complete a
one-time shop.
Arm 1 (Control): Participants will experience a default version of Bahrain e-Mart which
replicates the traditional shopping experience of online grocery stores with no FOP labels.
Arm 2 (MTL): Same as Arm 1 Bahrain e-Mart except that Multiple-Traffic Light (MTL) labels are
displayed on food and beverage products. Multiple Traffic Light is a nutrition labelling
system wherein each nutrient attribute constituting this label (i.e. sugar, saturated fat,
fat, and sodium) is assigned different colours according to whether the amount of that
nutrient is low (green), medium (amber) or high (red).
To collect shopping data as close as possible to shoppers' actual grocery carts, the
investigators set a minimum spending value per person per week and adjusted the total minimum
spending value depending on household size. Additionally, participants will have to shop from
at least 4 different Bahrain e-Mart categories to successfully checkout their cart. Finally,
participants will be informed that they may win rebates ranging from 25% to 100% on their
grocery order. This will be done by implementing an electronic prize wheel that the
participants will spin after successfully checking out their cart. Every participant will
have an equal chance of winning. If they win any of the rebates, they will be expected to
conduct a grocery shop in a market/supermarket of their choice to purchase the same items
ordered on the Bahrain e-Mart grocery store website. The maximum rebate they can get after
spinning the wheel will be based on their drawn rebate rate and the total order amount on
Bahrain e-Mart (e.g., If participants win a 50% rebate and the total order amount on Bahrain
e-Mart was BD 40, the maximum rebate they can get would be BD 20). If the exact same item
cannot be found, they are allowed to purchase a similar item as a replacement instead.
Replacements are subject to the guidelines provided in the participant information sheet and
consent form that they must sign prior to enrolment and randomisation into either of the
study arms.
Subject related procedures
Participants will be recruited if they are Kingdom of Bahrain residents aged 21 years or
older, can speak and write Arabic or English and are primary weekly shoppers for their
households. Recruitment will be done by a market research company utilising in-person
intercept surveys. This survey aims to recruit participants across 4 cities and 20 locations
(e.g., shopping malls). The Duke-NUS team is not directly involved in data collection.
Participants will be intercepted in-person by the interviewer and be briefed about the study.
Those who are interested will first be invited to select their preferred language (i.e.
English or Arabic) and then complete the online screener questionnaire using a tablet. All
eligible participants will then be asked to enter their mobile number in a textbox field and
will be required to give consent for the investigators to use their personal data for
registration purposes, that is, to verify via OTP that their mobile number has never been
entered into the system before. This ensures that the participant is not a duplicate
participant and has not attempted to join the study before. Participants who decide to
withdraw from the study after screener completion and provision of their mobile number will
be ineligible to participate in the study again.
Participants will subsequently be asked to read an information sheet and provide their
consent to enroll in this study by entering their name and email address in a textbox field.
Upon consent, participants will be redirected to complete a baseline questionnaire to collect
demographic and health characteristics, which should take approximately 10 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. Investigators ask this question to allow for testing whether the
intervention 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
intervention on diet quality, a precursor to non-communicable diseases (NCDs), the collection
of household health indicators is reasonable.
Upon completion of the baseline survey, participants will be randomly assigned to one of the
2 shopping conditions (Arm 1 [Control] or Arm 2) and redirected to Bahrain e-Mart to log in
and begin shopping immediately.
Participants will be informed that the shop must be completed with the aim of purchasing
enough groceries for all members of their household for a week. If they have a household size
of 8 members or less, they are required to spend a minimum of BD 10 (≈USD 26) for each member
of their household, and their expenditure should not exceed twice the total minimum. For
instance, if they have 4 members their minimum expenditure should be BD 10 X 4 = BD 40 and
their maximum expenditure should be BD 40 x 2 = BD 80. However, if they have a household size
of more than 8 members, they are required to spend a minimum of BD 80 and a maximum of BD
160. Additionally, participants must select products from at least 4 different Bahrain e-Mart
Store categories (e.g. Dairy and eggs, fruits and vegetables etc.).
The interviewer will stand at a distance to allow participants to complete their shop
privately up until the prize wheel, unless the participant raises any questions. The time
spent completing the shop is expected to be approximately 15-20 minutes. Subsequently,
participants will be required to complete a post-study survey which should take around 3-5
minutes to complete.
Upon completion of the post-study survey, participants will spin a random electronic prize
wheel. Depending on the results of the prize wheel, their shopping trip may or may not
involve actual purchases. Participants may win rebates ranging from 25% to 100% based on
their total order amount on Bahrain e-Mart.
To claim their rebate, participants are expected to email the market research company ONE
image of their purchased grocery items and ONE clear image of the itemized grocery receipt
for verification within 14 days from the time of study completion, which is after the
participant spins the prize wheel. If no claims have been received via email within the
stipulated time, the rebate will be forfeited. Please note that participants will still
receive BD 2.5 via online transfer as stated in the participant information sheet.
Once the market research company validates the two images above, the study reimbursement and
rebate amount will be transferred to the participant via online transfer. This will be done
within 24 working hours of the company receiving the images.
If the prize wheel lands on "BD 2.5", then no further action is required. The study
reimbursement will be transferred to the participant via online transfer immediately upon
study completion. The study reimbursement of BD 2.5 will be given to all participants,
regardless of the outcome of the prize wheel. The prize wheel only determines the additional
rebates that participants may win.
All individuals who provided their consent to join this study will be emailed a copy of the
full information sheet and consent form as well as the debriefing sheet when they complete
the study (i.e., after participant has spun the wheel of rebate) or if they choose to
withdraw from the study. This is the same for participants who land on "BD2.5". The
interviewer will remind participants to review the debriefing sheet on their own.
Analysis Plan
An ordinary least square model will be used to compare the primary and secondary outcome
variables between the MTL arm and the control arms. The model will be adjusted for potential
confounders including age, gender, household size, education level, income, and prevalence of
diet-related health conditions that may affect the outcomes.
