Perceived Effectiveness of Salt Warning Labels on a UK Restaurant Menu: a Real-world Pilot Experiment
Phase: NA
Conditions: Food Selection
Sponsor: University of Liverpool

Study protocol 
Study title: Perceived effectiveness of salt warning labels on a UK restaurant menu: a real-world pilot 
experiment  
Short title: Salt warning label restaurant study 
ID: rfj78drdsu52lsbw3kztnbpne8xdao 
Document date: 03/06/2024 
Investigators: Dr Rebecca Evans1, Ms Jane Brealey1, Dr Natasha Clarke2, Dr Jennifer Falbe3, Dr Amy 
Finlay1, Dr Andrew Jones, Ms Paula Thorp1, Dr Rozemarijn Witkam1, & Prof Eric Robinson1 
Affiliated institutions: University of Liverpool, Bath Spa University2, University of California, Davis3 
Funder: NIHR BMC 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Background 
Diet-related disease is a key driver of poor population health, and social inequalities in health (1). In 
England, adults consume 40% more salt than the national guidelines (no more than 6g per day), and 
this is associated with increased risk of stroke and cardiovascular disease (2, 3). This excess intake is 
largely driven by processed food, and food eaten out of home (2, 3). Indeed, there are some 
restaurant menu items that contain over half, or even an entire day’s worth of salt. Currently, there 
are no policies that address or make UK consumers aware of these ‘excessive’ menu items. 
In a handful of cities in the United States (US), policy has been introduced that requires ‘excessive’ 
menu items to be indicated by a nutrient warning label. Indeed, in 2016 and 2019 respectively, New 
York City (NYC) and Philadelphia enacted a law requiring chain restaurant menu items that exceed 
the daily recommended limit for sodium in the US (≥ 2300mg) to feature a sodium warning label (see 
Figure 1) (4). In 2023, also in NYC, the Sweet Truth Act was signed into law, which requires chain 
restaurants to include added-sugar warning labels on menu items (including drinks) containing more 
than a day’s worth of added sugar according to US guidelines (> 50g) (see Figure 2) (5). There is 
overwhelming support for these policies in the US; for example, 85% of NYC residents support the 
added sugar warnings, and those who visit chain restaurants more frequently demonstrate the 
greatest support (6).  
Figure 1: Sodium warning labels on a restaurant menu 
 
Figure 2: Added sugar warning labels on a restaurant menu 

 
Experimental evidence suggests that nutrient warning labels on restaurant menus can help to inform 
consumers and nudge them to make healthier food choices. An online randomised controlled trial 
(RCT) of US adults found that icon-only and icon-plus-text added-sugar warning labels demonstrated 
greater perceived message effectiveness ([PME], product unpleasantness, health concern, 
discouragement from consumption) than the control label (QR code) (7). Another online RCT of US 
adults found that added-sugar warning labels on fast-food and full-service restaurant menus reduced 
the relative probability of ordering ≥1 high-added-sugar item by 2.2%, reduced added sugar ordered 
by 1.5g, (4.9g if the label was noticed), and improved knowledge of added-sugar content (8). 
Likewise, a series of online RCTs demonstrated that sodium warning labels reduced average sodium 
ordered from restaurants (by 19 – 81mg), and increased both knowledge of sodium content and 
perceived health risks compared with no label (9). Finally, in an online RCT of Uruguayan adults, 
separate nutrient warning labels (black octagons featuring the word ‘excess’) for total fat, saturated 
fat, sugars, and sodium on menu items in a mock online ordering website reduced the proportion of 
participants selecting an ‘excessive’ item by 14% (10). 
Post-implementation evaluation of nutrient warning label policies on restaurant menus is largely 
positive. In NYC, following implementation of sodium warning labelling, mean sodium content of 
purchases significantly decreased (-524mg) in full-service restaurants (FSR), relative to Yonkers (a 
different city in New York) which did not implement these labels (11). No significant change was 
observed in quick-service restaurants (QSR) (11). In terms of menu item reformulation, sodium 
content of items per serving in FSR and QSR in NYC approximately one year pre- and one year post- 
enforcement of the sodium warning icon rule was not observed to significantly differ (12). However, 
findings may be limited by follow-up data collection occurring less than one-year post-enforcement; 
additional time may be needed for restaurants to reduce the sodium content of menu items. 
To date, the impact of nutrient warning labels has not been tested in a real-world randomised 
controlled trial (i.e., in a restaurant), or in a UK context. Recent work suggests that UK consumers 
support the introduction of nutrient warning labels, and their PME was rated as significantly higher 
relative to a control label (QR code) (13). This study aims to test the effect of a menu featuring salt 
warning labels (design informed by previous work (13)) on perceived message effectiveness relative to 
a menu with no labels in a real-world restaurant environment. The study will also act as a pilot 
experiment for examining the impact of the salt warning label on food choice and subsequent salt 
intake in real-world conditions. 

Primary objectives: 
• 
To measure the PME of a menu featuring salt warning labels relative to a menu with no 
labels 
• 
To measure label awareness, perceived knowledge gain, and perceived influence of the label 
on food choice 
 
Secondary objectives: 
• 
To identify whether there is an effect of the salt warning label on: 
o Food choice (label/no label) 
o Total salt selected 
o Total salt intake 
• 
To examine support for the introduction of a salt warning label policy in the UK 
 
Experimental design 
The study will be a between-subjects randomised controlled trial design. The between-subject factor 
is the menu labelling. In the experimental condition, a nutrient warning label will be placed next to 
menu items that are high in salt. In the control condition, there will be no labels. The outcome will be 
(i) perceived message effectiveness, (ii) salt selected, label (y/n) selected, and salt intake. This will 
allow us to examine whether the salt warning label intervention impacts perceived message 
effectiveness and food choice relative to the control condition. 
 
Participants and recruitment 
Recruitment 
Participants will be recruited via social media adverts (Facebook, Instagram), a database maintained 
by researchers at the University of Liverpool, and word of mouth. Interested participants will be 
asked to click a link which will take them to an online screening questionnaire (Appendix A). 
Participants can bring a maximum of nine guests to the restaurant. Guests will be pre-screened in 
advance to ensure eligibility. In pre-study instructions participants will be informed that any guests 
they bring will participate in the study.  
Sampling 
We will stratify based on education level to be largely representative of the UK population (14, 15). 
We will recruit (approximately): 
• 
50% NQF 4 Level 4 or above (University degree or equivalent) and 50% NQF Level 3 or below 
(no University degree)  
We will also aim to fulfil the following quotas for age and gender, based on the composition of the 
UK population (16, 17): 
• 
50% 18 – 39 and 50% 40 and over 
• 
50% female and 50% male 

We will only recruit up to 10% of the sample as current University students. Students have a high SEP 
in terms of education, but typically have low disposable income, which may impact relative health 
motives. This could distort the results if students are recruited in high numbers. 
Inclusion and exclusion criteria 
Participants are eligible to take part if they: 
• 
Are a UK resident 
• 
Are aged 18 years and above 
• 
Are fluent in English 
• 
Eat an out-of-home meal at least once a month on average 
• 
Have no dietary allergies 
• 
Are not vegan 
There are no additional exclusion criteria as this is a real-world study. 
 
Methods 
Procedure 
Participants will be asked to attend one session at a restaurant from Monday – Saturday between 12 
– 5pm. All participants will be asked to verbally consent to taking part in the study, and will be given 
the opportunity to ask questions before the study begins.  
Participants will be asked to order lunch from a menu. The menu will either feature nutrient warning 
labels next to the relevant menu items (experimental condition), or no labels (control condition). A 
researcher will ask participants to write their order down on an order form, communicate the order 
with the kitchen, photograph the meal when it is ready to be served, and photograph the plate when 
the participant is finished with the meal in order to estimate amount consumed. 
After finishing their meal, participants will be asked to fill out an online questionnaire (on an iPad) 
about their sociodemographic characteristics, health motives, label awareness, salt awareness, 
perceived message effectiveness, perceived knowledge gain, perceived influence, and support for 
the introduction of a restaurant salt warning label policy in the UK. The questionnaire will also ask (i) 
whether any food or drink items were shared with other participants, and, if so, what item(s) were 
shared and (ii) whether they added any condiments to their meal (see Appendix E). 
Participants will be reimbursed with £25 for their time, as it is thought that this would cover most of 
their lunch, time, and travel, and would incentivise people from different SEP strata to participate. As 
a default, participants will:  
• 
Pay for their meal and receive a £25 reimbursement via invoice 
However, if a participant expresses that this will be an issue, they can choose to: 
• 
Have the meal cost taken from their reimbursement. I.e., a researcher will use a prepaid card to 
pay for the meal. If they spend less than £25, they can opt to receive the remaining money via 
invoice. If they spend more than £25, they will have to pay this difference at the restaurant. 
To measure food intake for the rest of the day after the intervention took place, participants will 
receive a link for a dietary recall questionnaire the next morning by e-mail (intake24). We will ask the 

participant to complete the dietary recall questionnaire the same day they received the e-mail (i.e. 
the day following the intervention). Following completion, participants will be emailed a debrief form 
regarding the study aims (see Appendix F).  
We will conduct a small pilot experiment with one table of participants (n = 4) prior to study 
commencement in order to run through the procedure with all involved researchers.  
Setting 
The study will be conducted in a full-service restaurant in Liverpool City Centre. 
Intervention 
Participants will be asked to order lunch from a menu consisting of main dishes and light bites/small 
plates. In the control condition, participants will be given a menu with no labels (see Figure 3). In the 
experimental condition, participants will be given a menu with nutrient warning labels corresponding 
to items that are high in salt (see Figure 4). The labels will feature beneath the menu item name and 
will be the same height as the name text, as per nutrient warning labelling guidelines for restaurant 
menus in Philadelphia (18). There will be a standard drink offering at each visit, including alcoholic 
drinks. 
Labels will be placed next to items that exceeded 50% of the adult daily recommended limit for salt 
in the UK (3g) (19).  
Participant groups will be randomised to either the experimental or control condition using a block 
randomisation schedule (https://www.sealedenvelope.com/simple-randomiser/v1/lists). Participants 
seated at the same table will be in the same condition. Therefore, to adjust for possible differences in 
group sizes and consequently numbers in each condition, we will randomise in blocks of 50. The 
menu contains eight main dishes and eight light bites/small plates (five of which are high in salt). 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Figure 3: Menu (A) for the control condition 
 
 
 

Figure 4: Menu (B) for the experimental condition 
 
 
 

Measures 
Participant characteristics 
Demographics 
Participants will be asked to report their gender, age and ethnicity. Self-reported height and weight 
data will also be collected to calculate body mass index (BMI), so participants can be classed as 
having underweight, healthy weight, overweight or obesity. 
Frequency of eating OOH 
“How often, on average, over the past year have you eaten out at a restaurant?” Response options: 
not in the last year, less than once per month, 1 – 3 times per month, 1 – 2 times per week, 3 times 
per week or more. 
Measures of socioeconomic position (SEP) 
• 
Education level  
Two measures of SEP will be collected. Education level (defined by the National Qualifications 
Framework [NQF] ranging from no formal qualifications [NQF1], GCSEs or equivalent {NQF2], A levels 
or equivalent [NQF3] to degree level or above [NQF4+](15)) will be recorded as evidence suggests 
that individuals with a higher education level are more motivated by health when making food 
choices (20).  
Employment status 
Participants will be asked what their employment status is. Response options: full-time; part-time; 
student; retired; temporary / permanently sick or disabled; looking after home / family; other. 
Primary outcomes 
PME 
PME will be measured using an adapted version of the UNC PME scale. The scale measures health 
concern, product attitude, and discouragement of product consumption (21). Participants will 
answer 3 PME questions using a Likert scale ranging from 1 – 5 anchored by “not at all” and “a great 
deal”: Prompt: “Think back to the menu that you ordered from…” “The menu made me concerned 
about the health effects of consuming items high in salt”, “The menu made consuming items high in 
salt seem unpleasant”, “The menu discouraged me from wanting to consume items high in salt”. The 
mean response to the three items will be calculated. PME is used as an early indicator of a health 
message’s potential to change behaviour (e.g., reduce selection of items high in salt) (22). The scale 
has been used extensively in similar experiments to identify the potential impact of nutrient warning 
labels, has strong construct validity, and is predictive of longer-term actual behaviour (21, 23-28).  
An attention check will be placed after the PME questions. “This question is an attention check, so 
please answer truthfully. How many times have you visited the planet Mars? Several times / Just 
once / Never”.  
Correct answer: Never 
Label awareness 

“Did you notice any warning labels next to any of the menu items when making your meal 
selection?” (yes/no).  
If [yes], “What did the label tell you about?” Response options: Healthy items, Organic, Calcium, 
Sustainable, Added sugars, Vegetarian, Unhealthy items, Salt, Fibre, Gluten Free, None of these, Not 
sure.   
If [yes], “Please describe what the label said” (open text response). Responses that mention high in 
salt or similar will be coded as aware. 
Salt awareness 
“Did you think about the salt content of the meals when making your selection?” (yes/no) 
Note: For the below questions, both groups will be shown an image of the labelled menu. Some 
question phrasing is slightly altered for the control condition.  
Perceived knowledge gain 
“Did you learn something new from the salt labels on the menu?” (yes/no). 
Control: Same as above 
Perceived influence 
“Did the salt label influence which food you ordered from the menu” (yes/no). 
“If [yes], how did the salt label influence your choice?” Response options: I avoided choosing a meal 
high in salt; I chose a meal high in salt; Other (free text response) 
Control: “Would the salt label have influenced what food you ordered from the menu?” (yes/no) 
If [yes], how would the salt label have influenced your choice? Response options: I would have 
avoided choosing a meal high in salt; I would have chosen a meal high in salt; Other (free text 
response) 
Policy support 
If the UK Government introduced policy requiring restaurant menu items high in salt to feature these 
labels, how would you feel?” Likert scale ranging from 1 – 5 anchored by “strongly oppose” and 
“strongly support”. 
Control: Same as above 
Additional thoughts on label 
“Please use this box to add any additional thoughts which you may have about the salt label” (open 
text response). 
Control: Same as above 
 
 
 
 

Secondary outcomes 
Total salt purchased 
Determined based on the total order of the participant, including food and drink. Prior to study 
commencement, all menu items will be sent for nutritional analysis to determine salt content/100g. 
Menu items will be weighed before being sent for analysis using kitchen scales (Vitafit VT706), so 
that specific salt content per serving can be calculated.  
Labelled item selected 
Determined based on whether the food item selected featured a high in salt warning label (yes = 1, 
no = 0).  
Total salt consumed 
Salt consumption will be determined from the order that the researcher takes and an estimation of 
the proportion of the meal that was consumed. The researcher will take a photograph before and 
after consumption and will estimate the percentage consumed component(s) of the meal, taking into 
account whether participants leave a proportion of all meal components or specific components 
(e.g., low salt or high salt components). Participants will also be asked whether they shared any of 
their meal with someone else. A random 10% selection of percentage estimates will be performed by 
a second researcher to measure reliability. Food consumption will then be calculated by subtracting 
an estimation of the proportion of the meal that was consumed (taking into account if any has been 
shared) from the food purchase.  
Later salt intake 
Participants will receive a link to a dietary recall questionnaire (Intake24, https://intake24.co.uk/) via 
email the next morning after taking part in the study, which they will be prompted to complete 
before midnight that day. They will be asked to provide as much detail as possible on what they had 
for dinner, snacks, and drinks after the restaurant visit. Based on this information and salt values 
calculated by Intake24, we will estimate the total salt consumed by the participants for the rest of 
the day after the visit.  
Other macronutrient intake 
Total kcal, sugar, and saturated fat intake [i.e., other nutrients that are not the main warning focus] 
will be calculated based on the nutritional content of the order of the participant. 
 
Additional measures 
Food choice motives 
The “health” subsection of the Food Choice Questionnaire (29) will be used to measure the extent to 
which health motives may influence participants’ food choices. The subsection consists of 6 items, 
e.g. “It is important to me that the food I eat on a typical day….is nutritious” answered on a 4-point 
Likert scale ranging from “Not at all important” to “Very important”.  We will calculate the mean 
response for the six items. 
 Aim guessing 

Participants are told that the study is about dining habits in restaurants. At the start of the post-meal 
assessments, participants will be asked what they think the aims of the study were (free text 
response). Any participant that guesses the study aims to be investigating the influence of food 
warning labels on food choice will be coded as being aware of study aims. One researcher will code 
awareness of aims (R.E.) and a second researcher will independently verify the coding. 
 
Study flow 
Recruitment 
- 
Participants will be recruited via online adverts, word 
of mouth, and an existing participant database 
maintained by researchers at the University of 
Liverpool. 
- 
A link to the screening questionnaire will be provided. 
(Appendix A) 
- 
Participants will be stratified by SEP, age, and sex. 
Information sheet and informed 
consent 
- 
Eligible participants will be e-mailed an information 
sheet (Appendix B) and consent form (Appendix C). 
Participants can ask any questions about the study via 
e-mail. 
- 
The researcher will schedule a study visit day, leaving 
30-minute 
gaps 
between 
participant 
groups. 
Participants may bring a maximum of nine guests aged 
18 years or older to the restaurant.  
- 
As the guests did not yet receive an online information 
sheet and consent form, all participants will also be 
provided with information by the researcher and 
provide verbal consent. The researcher will answer 
any questions prior to the study. 
Meal choice task 
- 
Participants will be invited to visit the restaurant. They 
will be assigned in advance to either the control or 
experimental condition. Any guests will be in the same 
condition as the primary participant (i.e., participants 
will be randomised by table). They will also be given a 
participant number which they will be required to 
enter in any questionnaire they complete.  
Control condition 
- 
Participants 
will 
receive a standard 
menu 
without 
nutrient 
warning 
labels.  
Experimental condition 
- 
Participants 
will 
receive 
a 
menu 
featuring a nutrient 
warning label next to 
items high in salt. 
Text at the bottom of 
the menu will read 
“[label 
image] 
indicates that the salt 
content of this item is 
higher than 50% of 
the 
daily 
recommended 
limit 
(6g per day). High salt 

intake can increase 
blood pressure and 
risk of heart disease 
and stroke.” 
- 
The participants will be asked to order lunch from the 
menu and a drink (optional) and write this down on an 
order form (Appendix D) 
- 
A researcher will communicate the order with the 
kitchen, take a photo of the meal when it is ready to 
be served and take a second photo when the 
participant is finished with the meal. The researcher 
will send themselves each photo on WhatsApp 
labelled with the participant ID. 
Post-meal assessments 
(Qualtrics) (Appendix E) 
- 
After finishing their meal, participants will be 
provided with an iPad. They will answer a question 
about what they think the aim of the study was in an 
open-ended response format.  
- 
Next, participants will complete measures of PME, 
label awareness, salt awareness, perceived 
knowledge gain, perceived influence, and policy 
support. 
- 
Finally, participants will answer questions on 
demographic characteristics (including frequency of 
eating OOH) and health motives.  
Later intake 
- 
After the restaurant visit (same day), participants will 
receive a link to an online questionnaire assessing 
their dietary intake for the rest of the day after the 
restaurant visit, to be completed before they go to bed 
(Intake24). 
- 
This will enable us to calculate salt consumed post 
intervention for the rest of that day. 
- 
They will also be requested to answer some additional 
questions on demographic characteristics. 
Additional demographic 
questions (Appendix F) and 
debriefing (Appendix G) 
(Qualtrics) 
- 
After completing the dietary intake questionnaire, 
participants will be asked to answer some additional 
questions on demographic characteristics.  
- 
Upon completion, participants will be debriefed on 
study aims. 
Reimbursement 
- 
Participants will receive £25 which will likely cover 
their lunch costs and serve as an incentive for people 
from different SEP strata to participate. Participants 
will either (i) pay for their own meal at the restaurant 
and receive £25 via invoice or (ii) have their meal paid 
for by a researcher using a prepaid card; if this costs 
less than £25, they can request to receive the 
remaining amount via invoice, if this costs more than 
£25, they  will need to pay the difference at the 
restaurant.  
 
 

 
Statistical analysis  
Participant characteristics 
Participant characteristics will be presented overall and by experimental condition in a table. Data 
will include age, gender, ethnicity, highest educational qualification, employment status, BMI, 
frequency of eating OOH, and hunger. Continuous variables will be summarised as means and 
standard deviations, and categorical variables will be summarised as counts and percentages. 
Measured variables 
Primary 
A linear regression will be used to assess differences between menu conditions in terms of PME. The 
between-subjects predictor will be label condition, and the dependent variable will be PME.  
Highest education level (categorical: NQF level 4 or above, NQF level 3 or below) will be included as a 
covariate in the model to account for stratification (30). Health motives (continuous) will be included 
as a covariate as this may predict outcomes (e.g., health motivated individuals may be more likely to 
believe a menu with labels will change their behaviour) (30). Age and gender will also be included as 
covariates as previous work suggests that this can influence ratings of label PME and salt intake (13).  
Descriptive analysis will be used to report (overall and by condition) participants’ label awareness, 
salt awareness, perceived knowledge gain, perceived influence, and policy support (dichotomised 
into support/oppose). Logistic regressions will be performed to assess the odds of (i) being aware of 
the label, and (ii) being aware of the salt content of the meals in the labelled menu group, using the 
control menu group as the reference category. The same covariates as above will be included. 
Secondary 
Linear regressions will be performed to assess differences in menu conditions in terms of total salt 
purchase and total salt intake. The same covariates as above will be included. 
A logistic regression will be performed to assess the odds of selecting a high salt meal in the labelled 
menu group, using the control menu group as the reference category. The same covariates as above 
will be included. 
As some participants are likely to bring guests to the restaurant and guest tables are the unit of 
randomization, there may be clustering for outcome variables (i.e., the variation in PME and/or salt 
purchase/intake may be partially explained by table). We will test for clustering effects by comparing 
the within-table variability for outcome variables to the between-table variability. We will use the 
likelihood ratio test to ascertain the difference in likelihoods between the two. If this is statistically 
significant (p < .05) then there is enough evidence to suggest that there is a clustering effect of table 
groups eating together. If there is evidence of clustering then we will perform a series of linear mixed 
model analyses, with label condition as an independent variable, and table group as a random effect 
for primary and secondary outcomes.  
Exploratory analyses 
Linear regressions will be performed to assess differences in menu conditions in terms of later salt 
intake, and intake of other macronutrients. This is to examine whether individuals engage in any 
compensatory eating behaviour after seeing the labels (e.g., they are aware that they consumed a 

high salt meal and therefore reduce their salt intake later in the day), or whether intake of other 
macronutrients (e.g., calories) is impacted.  Again, the same covariates as above will be included.  
Sensitivity 
Sensitivity analyses will be conducted to test if results are the same after removing any participants 
that correctly guess the aims of the study (i.e., the effect of salt warning labels on food choice, or 
similar). If many participants identify the study aims (e.g., > 25%) we will examine if study aim 
awareness status moderates any effects of labelling by including this as a covariate (categorical) in 
analyses. Any deviations in findings from the main analyses will be reported. 
Missing data 
We do not foresee missing data being a problem as when we design measures in Qualtrics all fields 
will require a response, and all data will be collected by a researcher during the restaurant visit. 
However, it is possible that some participants will not complete the online questionnaire to assess 
later intake after the restaurant visit. Any missing data for later nutrient intake will be imputed.  
Multiple comparisons 
The alpha will be set at .05 for primary and secondary outcome analyses. To adjust for multiple 
comparisons, the alpha for exploratory analyses alpha will be reduced to .01. 
 
Sample size 
The label in the present study (or a similar label) has not previously been tested in a real-world UK 
context, in terms of PME or food choice. A RCT examining the effects of ‘high in’ added sugar labels 
on PME found large effects (d = 0.58 – 0.63) (7). A meta-analysis on food labelling found a small 
effect (OR = 0.65, or d = .24) of warning labels in terms of reducing consumers’ probability of 
selecting less healthy items (31). However, a RCT examining the effects of ‘high in’ sodium labels on 
salt (g) and ‘high in’ item choice found very small effects (d = 0.03 and 0.04 respectively) (9), but 
there are important methodological differences (e.g., menu size) between this study and the present 
study. The primary purpose of the present study is to examine PME, so we will therefore power the 
study for this primary outcome, but in doing so we will have reasonable power to detect small-
medium effects for our secondary outcome (food choice).  
In the present study, G power calculation indicates a minimum sample of 260 participants (130 per 
condition) will provide sufficient power (80%, two-tailed) to detect small-medium between condition 
effects (d = 0.35) of the salt warning label on PME, salt purchased, and salt intake using between-
subject ANOVAs (as planned).  
Prior to the study we do not know with certainty what the rate of participant recruitment will be, 
and effect size estimates have a degree of uncertainty. To balance the trade-off between costs (e.g., 
in research time, participant burden) and likelihood of the study providing convincing evidence, we 
will conduct interim analyses  When we have collected data for 260 participants (130 completers in 
each condition), we will conduct interim analyses to assess whether the results are convincing 
enough to conclude that an effect on PME and odds of selecting a high salt meal are present or 
absent (32). The interim analyses will examine the effect size estimates of these two outcomes and 
current statistical significance. If it is extremely unlikely that either of the predicted effects would be 
observed up to maximum sample size capacity (n = ~500) based on time and resource constraints, 
then we will cease data collection at this point and conduct planned analyses. However, if the 

observed effect size suggests that a detectable effect (d ≥ 0.25) is present but is not statistically 
significant, data collection will continue and we will attempt to recruit the largest possible sample 
size up until the end of September 2024 at the latest. In this scenario, consistent with best practice 
recommendations for interim analyses and to account for multiple testing, the p value for these 
outcomes will be adjusted to 0.025.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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menu items in New York City chain restaurants following enforcement of the sodium warning icon 
rule, 2015–2017. PLOS ONE. 2023;18(5):e0274648. 
13. 
Evans R, Robinson, E., Clarke, N., Falbe, J., Finlay, A., & Tzavella, L. Perceived effectiveness of 
salt warning label designs for UK products and menus: an online randomised controlled trial. 2024. 
14. 
Clarke N, Pechey E, Kosīte D, König LM, Mantzari E, Blackwell AK, et al. Impact of health 
warning labels on selection and consumption of food and alcohol products: systematic review with 
meta-analysis. Health Psychology Review. 2021;15(3):430-53. 
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ONS. Education and training statistics for the UK 2023 [Available from: https://explore-
education-statistics.service.gov.uk/find-statistics/education-and-training-statistics-for-the-uk. 
16. 
ONS. Male and female populations 2023 [Available from: https://www.ethnicity-facts-
figures.service.gov.uk/uk-population-by-ethnicity/demographics/male-and-female-
populations/latest/. 
17. 
ONS. Age groups 2023 [Available from: https://www.ethnicity-facts-figures.service.gov.uk/uk-
population-by-ethnicity/demographics/age-groups/latest/. 
18. 
Philly FF. Philadelphia displays sodium warning labels on chain restaurant menus. 2023 
[Available from: https://foodfitphilly.org/sodiumwarning/. 
19. 
NHS. Salt in your diet2023. Available from: https://www.nhs.uk/live-well/eat-well/food-
types/salt-in-your-diet/. 
20. 
Konttinen H, Sarlio-Lähteenkorva S, Silventoinen K, Männistö S, Haukkala A. Socio-economic 
disparities in the consumption of vegetables, fruit and energy-dense foods: the role of motive 
priorities. Public health nutrition. 2013;16(5):873-82. 

21. 
Baig SA, Noar SM, Gottfredson NC, Boynton MH, Ribisl KM, Brewer NT. UNC perceived 
message effectiveness: validation of a brief scale. Annals of Behavioral Medicine. 2019;53(8):732-42. 
22. 
Noar SM, Bell T, Kelley D, Barker J, Yzer M. Perceived message effectiveness measures in 
tobacco education campaigns: A systematic review. Communication methods and measures. 
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23. 
Grummon AH, Hall MG, Taillie LS, Brewer NT. How should sugar-sweetened beverage health 
warnings be designed? A randomized experiment. Preventive Medicine. 2019;121:158-66. 
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Hall MG, Grummon AH, Lazard AJ, Maynard OM, Taillie LS. Reactions to graphic and text 
health warnings for cigarettes, sugar-sweetened beverages, and alcohol: An online randomized 
experiment of US adults. Preventive medicine. 2020;137:106120. 
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Hall MG, Lazard AJ, Grummon AH, Higgins IC, Bercholz M, Richter APC, et al. Designing 
warnings for sugary drinks: A randomized experiment with Latino parents and non-Latino parents. 
Preventive medicine. 2021;148:106562. 
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Taillie LS, Chauvenet C, Grummon AH, Hall MG, Waterlander W, Prestemon CE, et al. Testing 
front-of-package warnings to discourage red meat consumption: a randomized experiment with US 
meat consumers. International Journal of Behavioral Nutrition and Physical Activity. 2021;18:1-13. 
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Taillie LS, Hall MG, Gómez LF, Higgins I, Bercholz M, Murukutla N, et al. Designing an effective 
front-of-package warning label for food and drinks high in added sugar, sodium, or saturated fat in 
Colombia: an online experiment. Nutrients. 2020;12(10):3124. 
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Noar SM, Barker J, Bell T, Yzer M. Does perceived message effectiveness predict the actual 
effectiveness of tobacco education messages? A systematic review and meta-analysis. Health 
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Holmberg MJ, Andersen LW. Adjustment for Baseline Characteristics in Randomized Clinical 
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Appendices 
Appendix A – Screening questionnaire 
Where do you live? 
o In the United Kingdom  (1)  
o In a different country  (2)  
 
 
 
 
Are you fluent in English? 
o Yes  (1)  
o No  (2)  
 
 
 
What is your age (in years)? 
________________________________________________________________ 
 
 
 
What is your sex? A question about gender identity will follow. 
o Male  (1)  
o Female  (2)  
 
 
 
Which of the following best describes your gender? 

o Man  (1)  
o Non-binary  (2)  
o Woman  (3)  
o Prefer to self-describe  (4)  
o Prefer not to say  (5)  
 
 
 
Are you a University student? 
o Yes  (2)  
o No  (3)  
 
 
 
What is your highest educational qualification? If you are a student, please select the qualification 
being studied for.  
o Less than high school (no formal qualifications)  (1)  
o High school completion (e.g., GCSEs or equivalent)  (2)  
o College or foundation degree (e.g., A Levels or equivalent)  (3)  
o Bachelor's degree  (4)  
o Master's degree  (5)  
o Doctorate or professional degree  (6)  
 
 
 

Do you have any dietary allergies? 
o Yes (please describe)  (1) __________________________________________________ 
o No  (2)  
 
 
 
Do you have any dietary requirements? 
o No  (1)  
o Vegetarian  (2)  
o Vegan  (3)  
o Other (please describe)  (4) __________________________________________________ 
 
 
 
How often, on average, over the past year have you eaten out (e.g., at a restaurant, café)? 
o Not in the last year  (1)  
o Less than once per month  (2)  
o 1 - 3 times per month  (3)  
o 1 - 2 times per week  (4)  
o 3 times per week or more  (5)  
 
 
Please provide your email address so that the researcher can contact you: 
 Make sure there are no typos in your email address. 
   
________________________________________________________________ 

Appendix B – Information sheet 
Liverpool Restaurant study  
  
You are being invited to participate in a research study. Before you decide whether to participate, it is 
important for you to understand why the research is being done and what it will involve. Please take 
time to read the following information carefully and feel free to ask us if you would like more 
information or if there is anything that you do not understand. Please also feel free to discuss this 
with your friends, relatives and doctor if you wish. We would like to stress that you should only agree 
to take part if you want to.  
  
1. What is the purpose of the study?  
To investigate dining habits in restaurants.  
  
2. Why have I been chosen to take part?  
             We are recruiting healthy volunteers who fulfil the following criteria:  
• 
Is a fluent English speaker  
• 
Is aged 18 or older  
• 
Eat out in restaurants or cafes at least once per month  
• 
Do not have a dietary allergy  
  
3. Do I have to take part?  
No. Participation in this research is completely voluntary. You are free to withdraw at any time 
without explanation and without incurring a disadvantage.   
  
4. What will happen if I take part?  
As part of the study, you will be asked to visit a restaurant to purchase and consume a meal. At the 
restaurant you will be met by a member of our research team. We will also ask you to complete a 
short questionnaire about your background and eating habits. After your visit to the restaurant, we 
will send you another online questionnaire for you to complete the next day. The research team can 
provide you with a full schedule for the study, if required.  
  
  5.     How will my data be used?  
The University processes personal data as part of its research and teaching activities in accordance 
with the lawful basis of ‘public task’, and in accordance with the University’s purpose of “advancing 
education, learning and research for the public benefit. University of Liverpool employee Victoria 
Heath (V.Heath@liverpool.ac.uk) acts as the Data Protection Officer for this study and any queries 

relating to the handling of your personal data can be sent to her or the principal investigator (see 
contact details below). Further information on how your data will be used can be found in the table 
below.  
How will my data be collected?  
Through questionnaires you complete.  
How will my data be stored?  
On a password protected computer server.  
How long will my data be stored for?  
Your personal data (e.g. name) will be stored for up 
to 28 days and then deleted. All other information 
will be stored indefinitely.  
What measures are in place to protect the 
security and confidentiality of my data?  
We will store all data on password protected 
computer servers and we never share any of your 
personal data outside of the research team for this 
project.   
Will my data be anonymised?  
After the study your personal information will be 
stored separately from your other questionnaire 
responses to create an anonymised data set. After 
28 days all personal information will be deleted, 
but up to this point you can contact us and ask to 
see your information or have it deleted.  
How will my data be used?  
Your anonymised data will be combined with other 
participants’ data in order to be analysed.  
Who will have access to my data?  
The research team for this project will have access 
to your data.  
Will my data be archived for use in other 
research projects in the future?  
After the research team have anonymised your 
data and completed this research project, they will 
place the anonymised data sets on an archive (e.g. 
Open Science Framework) in case any other 
researchers want to use it for future research 
purposes.   
How will my data be destroyed?  
Your personal data will be destroyed electronically 
(deleting the files and removing them from the 
computer server).   
  
    6.  Expenses and / or payments  
You will be compensated £25 for taking part in this research.   
  
    7.  Are there any risks in taking part?  
There are no anticipated risks to you if you take part in the study greater than would be expected in 
everyday life. If you have a severe food allergy then we suggest you do not take part as the study will 
involve eating out in a restaurant.   

  
    8.   Are there any benefits in taking part?  
There are no direct benefits, other than the monetary payment.  
  
    9.   What will happen to the results of the study?  
We intend to publish the results from this study in a scientific journal. However, as explained above 
any personal information you provide is deleted before this and you would therefore not be 
identifiable in report. If you are interested in the results of the study, please let us know and we will 
share the results of the study with you when we publish it.  
  
   10. What will happen if I want to stop taking part?  
You are under no obligation to take part in this study; it is completely your choice.  If you do decide 
to take part, you are free to withdraw at any time and without giving any reason or explanation. Data 
collected up until the period you withdraw may be used, but only if you are happy for this to be 
done.  Otherwise you may request that your data be destroyed and no further use is made of them.  
  
11.    What if I am unhappy or if there is a problem?  
If you are unhappy, or if there is a problem, please feel free to let us know by contacting Prof. Eric 
Robinson (contact details below) and we will try to help. If you remain unhappy or have a complaint 
which you feel you cannot come to us with then you should contact the Research Governance Officer 
on 0151 794 8290 (ethics@liv.ac.uk). Please provide details of the name or description of the study 
(so that it can be identified), the researcher(s) involved, and the details of the complaint you wish to 
make.  
  
12.    Who can I contact if I have further questions?  
Lead researcher  
Senior researcher  
Dr Rebecca Evans  
2.80, Eleanor Rathbone Building  
Bedford Street South  
University of Liverpool,  
Liverpool   
L69 7ZA,  
UK  
R.K.Evans@liverpool.ac.uk  
Prof Eric Robinson  
2.33b, Eleanor Rathbone Building  
Bedford Street South  
University of Liverpool,  
Liverpool   
L69 7ZA,  
UK  
eric.robinson@liverpool.ac.uk   

 
Data protection officer  
 
Victoria Heath  
The Foundation Building,  
765 Brownlow Hill,  
University of Liverpool,  
Liverpool,  
L69 7ZX,  
UK  
V.Heath@liverpool.ac.uk  
 
  
I confirm I have read the information sheet  
  
o 
Yes  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Appendix C – Consent form 
Participant Consent Form  
Research ethics approval number: 11251  
Title of the research project: Liverpool Restaurant study  
Name of researcher(s): Dr Rebecca Evans, Prof Eric Robinson   
   
1. 
I confirm that I have read and have understood the information sheet for the above study. I 
have had the opportunity to consider the information, ask questions and have had these answered 
satisfactorily.  
  
2. 
I understand that my participation is voluntary and that I am free to stop taking part and can 
withdraw from the study at any time without giving any reason and without my rights being affected. 
I also understand that I have the right to lodge a complaint.   
  
3. 
I understand that the information I provide is for research purposes (see information sheet) 
and it will be held securely in line with data protection requirements at the University of Liverpool. In 
addition, I understand that personal information collected about me that can identify me, such as my 
name, will never be shared beyond the study team.   
  
4. 
I understand that shortly after completing the study, researchers will keep my personal data 
(e.g. name) and store it separately from my other questionnaire responses for up to 28 days on a 
computer, so that my anonymised questionnaire responses can later be deposited in an online data 
archive for sharing and used by other authorised researchers to support other research in the future.  
  
5. 
I understand that I can ask for access to any of the information I provide and I can request   
the destruction or alteration of that information if I wish for up to 28 days after participating   
in the study. I understand that following this I will no longer be able to request access to or  
withdrawal of the information I provide because this information will have been deleted.   
  
  
6. 
I agree and consent to take part in the above study.   
  
  
__________________________ 
 
__________ 
 
______________________  
Participant name  
 
             Date 
 
 
Signature (initial)  
 
 
 
 
 
 
 
 
 

Appendix D – Order form 
ORDER FORM  
Booking Name: University of Liverpool  
Table Number:  
Group size:  
STUDY ID  INITIALS  
EMAIL ADDRESS  
MEAL  
DRINK  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Appendix E – Post-exposure assessments 
Please enter your participant ID. If you are unsure what this is, please ask the researcher. 
________________________________________________________________ 
 
 
 
Please select the letter which is circled on your sticker label. If you are unsure, please ask the 
researcher. 
o A  (1)  
o B  (2)  
 
End of Block: Default Question Block 
 
Start of Block: Aim guessing 
 
What do you think was the aim of this study? 
________________________________________________________________ 
 
End of Block: Aim guessing 
 
Start of Block: Food sharing 
 
Did you share any of the food or drink items? 
o Yes  (1)  
o No  (2)  
 
 
Display This Question: 
If Did you share any of the food or drink items? = Yes 

 
What items were shared? Please also give an estimation in % of how much of each item was shared. 
________________________________________________________________ 
 
 
 
Did you add any condiments (e.g., sauce, salt) to your food? 
o Yes  (1)  
o No  (2)  
 
 
Display This Question: 
If Did you add any condiments (e.g., sauce, salt) to your food? = Yes 
 
What condiments did you add? Please also give an estimation in teaspoons of how much of each 
condiment was added. 
________________________________________________________________ 
 
End of Block: Food sharing 
 
Start of Block: PME 
 
Please consider the following statements in relation to the menu you ordered from. 
 
Not at all (1) 
A little bit (2) 
Somewhat (3) 
Quite a bit (4) 
A great deal 
(5) 
The menu 
made me 
concerned 
about the 
health effects 
of consuming 
items high in 
salt. (1)  
o  
o  
o  
o  
o  

The menu 
made 
consuming 
items high in 
salt seem 
unpleasant. (2)  
o  
o  
o  
o  
o  
The menu 
discouraged 
me from 
wanting to 
consume 
items high in 
salt. (3)  
o  
o  
o  
o  
o  
 
 
End of Block: PME 
 
Start of Block: Attention check 
 
This question is an attention check, so please answer truthfully. How many times have you visited the 
planet Mars? 
o Several times  (1)  
o Just once  (2)  
o Never  (3)  
 
End of Block: Attention check 
 
Start of Block: Awareness 
 
Did you notice any warning labels next to any of the menu items when making your meal selection? 
o Yes  (1)  
o No  (2)  
 

 
Display This Question: 
If Did you notice any warning labels next to any of the menu items when making your meal selection? 
= Yes 
 
What did the label tell you about? 
o Healthy items  (1)  
o Organic  (2)  
o Calcium  (3)  
o Sustainable  (4)  
o Added sugars  (5)  
o Vegetarian  (6)  
o Unhealthy items  (7)  
o Salt  (8)  
o Fibre  (9)  
o Gluten free  (10)  
o None of these  (11)  
o Not sure  (12)  
 
 
Display This Question: 
If Did you notice any warning labels next to any of the menu items when making your meal selection? 
= Yes 
 
Please describe what the warning label said. 
________________________________________________________________ 

 
 
Page Break 
 
Did you think about the salt content of the meals when making your selection? 
o Yes  (1)  
o No  (2)  
 
End of Block: Awareness 
 
Start of Block: Additional assessments 
Display This Question: 
If Please select the letter which is circled on your sticker label. If you are unsure, please ask th... = B 
 
Here is the menu you ordered from. The menu features salt warning labels next to items that exceed 
50% of the daily recommended limit for salt intake: [menu B image] 
 
 
Display This Question: 
If Please select the letter which is circled on your sticker label. If you are unsure, please ask th... = A 
 
Here is a slightly different version of the menu you ordered from. The menu features salt warning 
labels next to items that exceed 50% of the daily recommended limit for salt intake: [menu B image] 
 
   
 
 
 
Did you learn something new from the salt labels on the menu? 
o Yes  (1)  
o No  (2)  

 
 
Display This Question: 
If Please select the letter which is circled on your sticker label. If you are unsure, please ask th... = B 
 
Did the salt labels influence which food you ordered from the menu? 
o Yes  (1)  
o No  (2)  
 
 
Display This Question: 
If Did the salt labels influence which food you ordered from the menu? = Yes 
 
How did the salt label influence your choice? 
o I avoided choosing a meal high in salt  (1)  
o I chose a meal high in salt  (2)  
o Other (please describe)  (3) __________________________________________________ 
 
 
Display This Question: 
If Please select the letter which is circled on your sticker label. If you are unsure, please ask th... = A 
 
Would the salt labels have influenced which food you ordered from the menu? 
o Yes  (1)  
o No  (2)  
 
 

Display This Question: 
If Would the salt labels have influenced which food you ordered from the menu? = Yes 
 
How would the salt labels have influenced your choice? 
o I would have avoided choosing a meal high in salt  (1)  
o I would have chosen a meal high in salt  (2)  
o Other (please describe)  (3) __________________________________________________ 
 
 
 
If the UK Government introduced policy requiring restaurant menu items high in salt to feature these 
labels, how would you feel? 
o Strongly oppose  (1)  
o Oppose  (3)  
o Neutral  (4)  
o Support  (5)  
o Strongly support  (6)  
 
 
 
Please use this box to add any additional thoughts which you may have about the salt label. 
________________________________________________________________ 
 
End of Block: Additional assessments 
 
Start of Block: Demographics 
 

What is your age (in years)? 
________________________________________________________________ 
 
 
 
What is your sex? A question about gender identity will follow. 
o Male  (1)  
o Female  (2)  
 
 
 
Which of the following best describes your gender? 
o Man  (1)  
o Non-binary  (2)  
o Woman  (3)  
o Prefer to self-describe  (4) __________________________________________________ 
o Prefer not to say  (5)  
 
 
 
What is your highest educational qualification? If you are a student, please select the qualification 
being studied for. 
o Less than high school (no formal qualifications)  (1)  
o High school completion (e.g., GCSEs or equivalent)  (2)  
o College or foundation degree (e.g., A Levels or equivalent)  (3)  
o Bachelor's degree  (4)  

o Master's degree  (5)  
o Doctorate or professional degree  (6)  
 
 
 
What is your current employment status? 
o Full-time  (1)  
o Part-time  (2)  
o Student  (3)  
o Retired  (4)  
o Unable to work due to sickness/disability  (5)  
o Looking after home/family  (6)  
o Unemployed  (7)  
o Other (please describe)  (8) __________________________________________________ 
 
 
 
What is your ethnic group? Choose one option that best describes your ethnic group or background. 
o Asian or Asian British Bangladeshi Chinese Indian Pakistani Any other Asian background  (3)  
o Black, Black British, Caribbean or African African Caribbean Any other Black, Black British, or 
Caribbean background  (5)  
o Mixed or multiple ethnic groups White and Black Caribbean White and Asian White and Black 
African Any other Mixed or multiple ethnic background  (6)  
o White English, Welsh, Scottish, Northern Irish or British Irish Gypsy or Irish Traveller Roma Any 
other White background  (7)  

o Other ethnic group Arab Any other ethnic group  (8)  
 
 
 
What is your height? 
o In centimetres:  (1) __________________________________________________ 
o OR in feet and inches:  (2) __________________________________________________ 
o Prefer not to say  (4)  
 
 
 
What is your weight? 
o In kilograms:  (1) __________________________________________________ 
o OR in stone and pounds:  (2) __________________________________________________ 
o Prefer not to say  (4)  
 
 
 
How often, on average, over the past year have you eaten out (e.g., at a restaurant, café)? 
o Not in the last year  (1)  
o Less than once per month  (2)  
o 1 - 3 times per month  (3)  
o 1 - 2 times per week  (4)  
o 3 times per week or more  (5)  
 

End of Block: Demographics 
 
Start of Block: Health motives 
 
Several different factors influence our choice of food. Read each item carefully and decide how 
important the item is to you. There are no right or wrong answers, we are interested in what is 
important to you.  It is important to me that the food I eat on a typical day… 
 
Not at all 
important (1) 
A little 
important (2) 
Moderately 
important (3) 
Very important 
(4) 
Contains a lot of 
vitamins and 
minerals (1)  
o  
o  
o  
o  
Keeps me healthy 
(2)  
o  
o  
o  
o  
Is nutritious (3)  
o  
o  
o  
o  
Is high in protein (4)  o  
o  
o  
o  
Is good for my 
skin/teeth/hair/nails 
etc. (5)  
o  
o  
o  
o  
Is high in fibre and 
roughage (6)  
o  
o  
o  
o  
 
 
 
 
 
 
 
 
 
 
 

 
Appendix F – Additional demographic assessments 
Please enter your participant ID. If you are unsure what this is, please ask the researcher. 
________________________________________________________________ 
 
 
 
Do you consider yourself to be a disabled person? 
o Yes  (1)  
o No  (2)  
o Prefer not so say  (3)  
 
 
 
Do you have any physical or mental health conditions or illnesses lasting or expected to last for 12 
months or more? 
o Yes  (1)  
o No  (2)  
o Prefer not to say  (3)  
 
 
 
How would you describe your national identity? (select all that apply) 
▢ British  (1)  
▢ English  (2)  
▢ Welsh  (3)  

▢ Scottish  (4)  
▢ Northern Irish  (5)  
▢ Other (please describe)  (6) __________________________________________________ 
▢ Prefer not to say  (7)  
 
 
 
What is your religion? 
o No religion  (1)  
o Buddhist  (2)  
o Christian (including Church of England, Catholic, Protestant, and all other Christian 
denominations)  (3)  
o Hindu  (4)  
o Jewish  (5)  
o Muslim  (6)  
o Sikh  (7)  
o Any other religion (please describe)  (8) 
__________________________________________________ 
o Prefer not to say  (9)  
 
 
 
Do you identify as trans? 
o Yes  (1)  

o No  (2)  
o Prefer not to say  (3)  
 
 
 
Which of the following best describes your sexual orientation? 
o Asexual  (1)  
o Bi/bisexual  (2)  
o Gay or lesbian  (3)  
o Queer  (4)  
o Straight/heterosexual  (5)  
o Pansexual  (6)  
o I identify in another way (please describe)  (7) 
__________________________________________________ 
o Prefer not to say  (8)  
 
 
 
Are you currently? (select all that apply) 
▢ Cohabiting or living with a partner  (1)  
▢ Divorced or civil partnership resolved  (2)  
▢ Married or in a civil partnership  (3)  
▢ Separated  (4)  

▢ Single  (5)  
▢ Other (specify, if you wish)  (6) __________________________________________________ 
▢ Widowed or surviving partner from a civil partnership  (7)  
▢ Prefer not to say  (8)  
 
 
 
In the last 12 months, have you taken any of the following types of leave? (select all that apply) 
▢ Adoption leave  (1)  
▢ Maternity leave  (2)  
▢ Paternity leave  (3)  
▢ Shared parental leave  (4)  
▢ Parental bereavement leave  (5)  
▢ Other (specify, if you wish)  (6) __________________________________________________ 
▢ None of the above  (7)  
▢ Prefer not to say  (8)  
 
 
 
Do you have any caring responsibilities? (if you share care responsibilities equally then please answer 
as the primary carer) 
o Yes  (1)  
o No  (2)  

o Prefer not so say  (3)  
 
 
Display This Question: 
If Do you have any caring responsibilities? (if you share care responsibilities equally then please... = 
Yes 
 
Please select all that apply: 
▢ Primary carer of a child or children (under 18 years)  (1)  
▢ Primary carer of a child or children who is disabled or has a health condition, or illness, or 
temporary care needs (under 18 years)    (2)  
▢ Primary carer or assistant for a disabled adult or adults (18 years and over)    (3)  
▢ Primary carer or assistant for an older person or people (65 years and over)  (4)  
▢ Secondary carer (another person carries out main caring role)   (5)  
▢ Prefer not to say  (6)  
 
 
 
What was the occupation of your main household earner when you were about aged 14? 
o Modern professional & traditional professional occupations such as: teacher, nurse, 
physiotherapist, social worker, musician, police officer (sergeant or above), software designer, 
accountant, solicitor, medical practitioner, scientist, civil / mechanical engineer.   (1)  
o Senior, middle or junior managers or administrators such as: finance manager, chief executive, 
large business owner, office manager, retail manager, bank manager, restaurant manager, 
warehouse manager. Clerical and intermediate occupations such as: secretary, personal assistant, 
call centre agent, clerical worker, nursery nurse.   (2)  
o Technical and craft occupations such as: motor mechanic, plumber, printer, electrician, gardener, 
train driver. Routine, semi-routine manual and service occupations such as: postal worker, 

machine operative, security guard, caretaker, farm worker, catering assistant, sales assistant, HGV 
driver, cleaner, porter, packer, labourer, waiter/waitress, bar staff.   (3)  
o Long-term unemployed (claimed Jobseeker’s Allowance or earlier unemployment benefit for 
more than a year).  (4)  
o Small business owners who employed less than 25 people such as: corner shop owners, small 
plumbing companies, retail shop owner, single restaurant or cafe owner, taxi owner, garage 
owner.  (5)  
o Other such as: retired, this question does not apply to me, I don’t know.  (6)  
o Prefer not to say  (7)  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Appendix G – Debrief text 
 
 Project Title: Dining habits in restaurants  
 
Researchers: Dr Rebecca Evans & Prof Eric Robinson  
 
We would like to thank you for your participation in this research. 
  
 Aims: The study aimed to assess how salt warning labels on restaurant menus affects what people 
choose to buy and eat. 
  
 Design: Some participants were provided with a standard menu (no nutrient warning labels) and the 
other participants were provided with a manipulated menu featuring nutrient warning labels next to 
meals high in salt. We will compare the perceived effectiveness of the menus in terms of 
discouraging salt intake, and the total amount of salt ordered and consumed with and without the 
labelling intervention. This will help us to examine if this could be an effective intervention to 
encourage healthier eating when eating out. 
  
 Thank you for your participation. If you have any further questions, please contact: 
 Lead researcher: Dr Rebecca Evans, University of Liverpool,  R.K.Evans@liverpool.ac.uk 
 Senior researcher: Prof Eric Robinson, University of Liverpool, Eric.robinson@liverpool.ac.uk 
  
 If you have any concerns or complaints that you wish to discuss with a person who is not directly 
involved in the research, please contact Research Ethics and Integrity Office at ethics@liv.ac.uk. 
  
 Please click the next arrow to ensure your response is submitted.