Socioeconomic Position and the Effect of kcal Labelling and PACE Labelling on Self-served Portion Size
Phase: NA
Conditions: Diet, Healthy, Food Selection
Sponsor: University of Liverpool

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STUDY PROTOCOL 
Study title: Socioeconomic position and the effect of kcal labelling and PACE labelling on self-served 
portion size 
Short title: Portion size labelling study 
Investigators: Lucile Marty, Caterina Franzon, Andrew Jones, Eric Robinson 
Funder: European Research Council 
TABLE OF CONTENTS 
 
1. 
BACKGROUND AND RATIONALE .................................................................................................... 3 
2. 
OBJECTIVES, OUTCOMES MEASURES AND HYPOTHESES ............................................................. 3 
3. 
EXPERIMENTAL DESIGN ................................................................................................................. 4 
4. 
PARTICIPANTS AND RECRUITMENT ............................................................................................... 4 
4.1. 
Recruitment ............................................................................................................................ 4 
4.2. 
Inclusion criteria ..................................................................................................................... 4 
4.3. 
Exclusion criteria .................................................................................................................... 4 
5. 
METHODS ....................................................................................................................................... 5 
5.1. 
Portion selection task ............................................................................................................. 5 
5.2. 
Measures of socioeconomic position .................................................................................... 6 
5.3. 
Measures of executive functions (EF) .................................................................................... 6 
5.4. 
Measure of health motivation in food choices ..................................................................... 7 
5.5. 
Measure of physical activity level.......................................................................................... 7 
6. 
STUDY FLOW ................................................................................................................................... 7 
7. 
STATISTICAL ANALYSES .................................................................................................................. 8 
7.1. 
Variables description .............................................................................................................. 8 
7.2. 
Missing data ......................................................................................................................... 10 
7.3. 
Participant’s characteristics ................................................................................................. 10 
7.4. 
Familiarity and liking ............................................................................................................ 10 
7.5. 
Main analyses ....................................................................................................................... 10 
7.6. 
Sensitivity analyses .............................................................................................................. 11 
7.7. 
Secondary analyses .............................................................................................................. 11 
7.8. 
Exploratory analyses ............................................................................................................ 12 
7.9. 
Sample size ........................................................................................................................... 13 
8. 
REFERENCES .................................................................................................................................. 14 
9. 
APPENDIX A: FOOD STIMULI DESCRIPTION ................................................................................. 17 
10. ......................................................................................................................................................... 17 

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11. 
APPENDIX B: TARGETED AUDIENCE (PROLIFIC WEBSITE) ....................................................... 18 
12. 
APPENDIX C: RECRUITMENT TEXT ........................................................................................... 19 
13. 
APPENDIX D: INFORMATION PAGE ......................................................................................... 20 
14. 
APPENDIX E: CONSENT PAGE ................................................................................................... 23 
15. 
APPENDIX F: REQUIREMENTS .................................................................................................. 25 
16. 
APPENDIX G: BASELINE QUESTIONNAIRE................................................................................ 26 
17. 
APPENDIX H: MEAL CHOICE TASK INSTRUCTIONS .................................................................. 29 
18. 
APPENDIX I: HEALTH AND WEIGHT CONTROL FOOD CHOICE MOTIVES ................................ 37 
19. 
APPENDIX J: INTERNATIONAL PHYSICAL ACTIVITY QUESTIONNAIRE .................................... 38 
20. 
APPENDIX K: FAMILIARITY ....................................................................................................... 40 
21. 
APPENDIX L: LIKING .................................................................................................................. 43 
22. 
APPENDIX M: DEBRIEFING ....................................................................................................... 44 
23. 
APPENDIX N: ADDITIONAL MEASURES .................................................................................... 46 
24. 
APPENDIX O: DEBRIEFING TEXT ............................................................................................... 54 
 

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1. BACKGROUND AND RATIONALE 
Socio-economic position (SEP) has a key-role in health and several studies have highlighted 
differences in dietary behaviour between people of lower and higher SEP as potential mediators of 
this relationship [1]–[3]. It has been shown that people of lower SEP are more likely to behave in 
ways that increase the likelihood of developing cardiovascular diseases and obesity (e.g., higher 
consumption of meat and fatty foods, alcohol consumption and smoking) [4], [5]. In developed 
countries, the prevalence of obesity and other chronic diseases has dramatically increased within all 
the socio-economic groups [6] but to a larger extent among poorer and less educated groups [7]. 
This social gradient might be explained by lower SEP being associated with increased energy intake 
[8]–[10]. 
Nutritional labelling is one of the most common intervention that has been implemented to reduce 
energy intake [11]. Nutritional labels provide consumers with different types of information (e.g. 
nutritional composition, energy content) in various ways (e.g. numerical, daily recommended intake, 
traffic lights) and may have a positive impact on food choices and energy intake [11]. However, 
Sarink et al. (2016) investigated the impact of kcal labelling in people of lower vs. higher SEP and 
showed that it may benefit more people of higher SEP than people of lower SEP, which may in turn 
increase health inequalities [12]. 
A novel form of labelling is Physical Activity Calorie Equivalent (PACE) which may be an alternative to 
numerical energy labelling [13]. PACE labelling aims to encourage healthier eating behaviours by 
providing an interpretation of the energy content of a food in terms of energy expenditure: how 
many minutes (time) or how many kilometres/miles (distance) of physical activity (e.g. walking, 
running, swimming, bicycle) are needed to burn off the corresponding energy [13]. PACE might be 
easier to understand compared to other nutritional labels because consumers do not need health 
literacy or have advanced numeracy skills to understand PACE [14]. However, in a recent study, 
Antonelli & Viera (2015) showed a stronger effect of PACE among people of higher compared to 
lower SEP, in particular among richer people [15]. 
The food choices of people of higher SEP are more motivated by health than those of people of 
lower SEP [16]. As information-based interventions typically rely on people being motivated by 
health in their food choices [17], the presence of nutritional labels may lead to healthier eating 
behaviours primarily among people of higher SEP. 
2. OBJECTIVES, OUTCOMES MEASURES AND HYPOTHESES 
OBJECTIVES 
OUTCOME MEASURES 
HYPOTHESES 
Primary objective 
 
To investigate the effect of 
labelling (kcal or PACE) on the 
total self-served energy among 
participants of lower and 
higher SEP. 
 
 
 
 
Total self-served energy in kcal 
from hypothetical meals 
 
 
Labelling (kcal or PACE) will influence 
the size of self-served portion and 
result in reduced total self-served 
energy among both participants of 
lower and higher SEP. 
 
Kcal and PACE labelling will exert a 
stronger effect on self-served energy 
among participants of higher compared 
to lower SEP. 
 

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PACE labelling will exert a stronger 
effect on self-served energy than kcal 
labelling. 
 
Secondary objectives 
 
To investigate the 
psychological processes that 
may explain the different 
effect of the intervention and 
whether health motivation 
and physical activity level 
mediate the differential effect 
of labelling (kcal or PACE) on 
total self-served energy among 
participants of lower and 
higher SEP. 
 
 
Executive function (tasks) 
 
 
 
 
 
 
 
Health motivation in food 
choices (questionnaire) 
 
 
 
 
 
 
 
Participants of higher SEP will have 
better executive function than 
participants of lower SEP, which will 
moderate the relationship between 
SEP and the effect of energy/PACE 
labelling on the total energy of the 
selected meal. 
 
Kcal/PACE labelling will exert a 
stronger effect on self-served energy 
among participants of higher SEP 
because they will be more motivated 
by health in their food choices than 
participants of lower SEP. 
 
 
3. EXPERIMENTAL DESIGN 
Participants will take part in an online survey. They will be asked to choose the amount of food they 
would like to eat based on pictures of 18 dishes sequentially displayed on the screen. They will be 
randomly allocated to four different groups: kcal labelling, PACE labelling (minutes to walk to burn 
off the calories), kcal and PACE labelling combined, no labelling, in a between subject design. 
4. PARTICIPANTS AND RECRUITMENT 
 
4.1. Recruitment 
Participants will be recruited through Prolific, an online recruitment platform in which participants 
are compensated proportionate to the time it takes to complete the online study (≈ 5£/hour reward 
participants). Participants’ recruitment will be stratified by gender (50% male, 50% female), student 
status (3.5% yes and 96.5% no) [18] and qualification levels (50% A level or below, 50% above A 
level) in order to recruit participants of lower and higher SEP. 
4.2. Inclusion criteria 
 
• 
UK residents, age ≥ 18 
• 
Fluent in English 
• 
Have access to a computer and Internet 
 
4.3. Exclusion criteria 
 
• 
Having any dietary restriction: 
o Vegetarian 
o Vegan 

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o Gluten-free 
o Sugar-free 
o Diary/lactose-free 
o Food allergy (e.g. milk, eggs, nut, wheat, fish, etc.) 
 
• 
Taking part more than once: 
Prolific is designed to avoid the same participant to take the same survey twice (i.e., one 
participant cannot access the study link twice). Each participant recruited on Prolific has a 
unique ID. If for some reasons a participant takes the survey twice, we will delete the second 
submission from the dataset by checking the ID duplicates. For the same reason, to avoid one 
participant takes the survey twice with different accounts, we will delete the second submission 
from the dataset by checking the IP duplicates. 
• 
Failing an attention check (Appendix G, item 9; Appendix H, item 10; Appendix O, item 4). 
• 
Completing the main task too fast, i.e., less than 2 sec per dish = less than 36 sec in total, that 
will be interpreted as careless or insufficient effort responding [19], [20]. 
 
5. METHODS 
 
5.1. Portion selection task 
Procedure 
Participants will be randomly allocated to one of the following groups: 
o kcal labelling (kcal+/PACE-); 
o PACE labelling (kcal-/PACE+); 
o kcal and PACE labelling (kcal+/PACE+); 
o no labelling (kcal-/PACE-). 
They will be asked to choose the amount of food they would like to eat in 18 hypothetical meals 
sequentially displayed on the screen. The first picture of each dish will show 20 kcal of this dish on a 
white plate. Participants will be able to virtually ‘serve themselves’ the amount of food they would 
like to eat by increasing or reducing the quantity on the plate using the arrow keys on their keyboard 
(to increase = right key; to decrease = left key). Energy content will increase by 20 kcal each time 
they will tap the right arrow key (max. 1000 kcal). Participants will have to increase the portion size 
at least once (i.e., at least one tap on the right arrow key) to be able to confirm their choice using 
the spacebar. The 18 dishes will be randomised in order. 
Foods 
The food stimuli are based on a previously published work by Whitelock et al. (2018) (Appendix A). 
For each dish, 50 pictures have been taken to reflect the increase in portion size. The number of 
calories increases 20 kcal by 20 kcal from a minimum of 20 kcal (first picture) to a maximum of 1000 
kcal (50th picture) [21]. 
Interventions  
For each portion and dish, participants will see on the screen a label showing the number of calories, 
physical activity calories equivalent or both. Labels are adapted from Swartz et al., 2013 [22]. 
Kcal labelling (kcal+/PACE-) 

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Participants allocated to this group will see on the screen the amount of food 
increasing or decreasing based on how many times they tap on the corresponding 
keys and a real-time kcal counter synchronised with the food amount changes (i.e., 
increasing/decreasing). 
PACE labelling (kcal-/PACE+) 
Participants allocated to this group will see on the screen the amount of food 
increasing or decreasing based on how many times they tap on the corresponding 
keys and a real-time PACE counter (as minutes needed to walk to burn off the 
calories) synchronised to the food amount changes (i.e., increasing/decreasing) with 
4 min being equivalent to 20 kcal [13]. 
Kcal and PACE labelling (kcal+/PACE+) 
Participants allocated to this group will see on the screen the amount of food 
increasing or decreasing based on how many times they tap on the corresponding 
keys and a real-time kcal and PACE counters synchronised to the food amount 
changes (i.e., increasing/decreasing). 
No labelling (kcal-/PACE-) 
Participants allocated to this group will only see on the screen the amount of food 
increasing or decreasing based how many times they tap on the corresponding keys. 
5.2. Measures of socioeconomic position 
Five measures of socioeconomic status will be included. Participants will be asked to report: 
- 
their highest educational qualification; 
- 
their number of years in higher education; 
- 
their current employment status; 
- 
their household income and their household composition; 
- 
a subjective measure of their socioeconomic position using the MacArthur Scale of 
Subjective Social Status (SSS) [23]. 
 
5.3.  Measures of executive functions (EF) 
Cognitive measures of EF 
Inhibition is the ability to suppress impulsive or automatic responses (e.g., not choosing unhealthy 
foods). A Stroop task will be used to measure inhibition (≈2min.30sec.). In this task, participants are 
given colour words written in colour and are asked to indicate the colour of the word (not its 
meaning) by key press as fast as they can without making too many errors. The task included three 
types of trials: 
- 
Congruent trials: colour word and the colour it is presented in are the same; 
- 
Incongruent trials: colour word and the colour it is presented in are not the same; 
- 
Control trials: coloured rectangles. 
The task includes 4 colours (red, green, blue, black) x 3 colour-stimuli congruency (congruent, 
incongruent, control) x 7 repetitions = 84 trials randomly sampled. 

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Working memory is the ability to monitor the relevance of incoming stimuli and update information 
in memory as required and is implied in goal-shielding (e.g., stick to healthy eating goals). A 
backwards digit-span task will be used to measure working memory (≈7 min.). This task will require 
participants to repeat series of digits of increasing length in the reversed order. Depending on 
performance, participants move up a level or down a level. The first trial is a sequence of two visual 
digits. Assessment is 14 trials in total. 
5.4. Measure of health motivation in food choices 
The Food Choice Questionnaire, developed by Steptoe et al. (1995), measures the motives related to 
food choice, including health. We will use the ‘Health’ and ‘Weight control’ subscales of this 
questionnaire [24]. 
5.5. Measure of physical activity level 
The International Physical Activity Questionnaire – Short Version (IPAQ-SF) will be used to assess 
the physical activity level. The IPAQ-SF includes 7 items and records the activity of four intensity 
levels: 1) vigorous-intensity activity such as aerobics, 2) moderate-intensity activity such as leisure 
cycling, 3) walking, and 4) sitting [25]. Although the original authors recommended to ask about the 
last 7 days of recalled physical activity, due to the context in which this study will be run, i.e., self-
isolation of UK population due to COVID-19 propagation preventive measures, we will ask about a 
usual week of recalled physical activity: number of days per week and how much time per day a 
participant usually does each of the four types of activity. 
5.6. Familiarity and liking of the test foods 
Participants will be presented with the picture of the 600 kcal portion of each food, as UK public 
health guidelines recommend energy consumption ≤600 kcal for a main meal [26], and asked: 
- 
“Have you ever eaten this food?” Answers: yes or no (familiarity) 
- 
“How much do you like this food?” Answers on a 100-point visual analogue scale (anchors: 
not at all, extremely) (liking) [21] 
 
6. STUDY FLOW 
RECRUITMENT 
(Prolific) 
▪ 
Predefined screening questions of Prolific website will be used to 
target the sample (Appendix B) 
▪ 
Participants who meet the inclusion/exclusion criteria will be 
emailed by Prolific and/or offered to complete our study on their 
Prolific account (Appendix C) 
▪ 
Eligible participants who want to take part on the study will click 
on the start button and be redirected to our study website 
(Inquisit) 
INFORMED CONSENT 
▪ 
Participants will read the information sheet (Appendix D) 
▪ 
Participants who want to proceed will tick a consent box 
(Appendix E) 
RANDOMISATION 
▪ 
Participants will be equally randomised and allocated to one of 
the four experimental groups using Inquisit software 
BASELINE 
ASSESSMENTS 
▪ 
Participants will complete a baseline questionnaire on 
demographics (Appendix G) 
MEAL CHOICE TASK 
▪ 
Instructions will be displayed (Appendix H) 
▪ 
Meals will be displayed in randomised order 

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Energy labelling 
(kcal+/PACE-) 
PACE labelling 
(kcal-/PACE+) 
Energy and 
PACE labelling 
(kcal+/PACE+) 
No labelling 
(kcal-/PACE-) 
EXECUTIVE FUNCTION 
Tasks randomised in order: 
▪ 
Inhibition (Stroop task) 
▪ 
Working memory (backwards digit-span task)  
HEALTH MOTIVATION  
▪ 
Health and weight control subscales from the Food Choice 
Questionnaire (Appendix I) 
PHYSICAL ACTIVITY 
LEVEL 
▪ 
International Physical Activity Questionnaire – Short Version 
(IPAQ-SF) (Appendix J) 
FAMILIARITY AND 
LIKING 
▪ 
For each dish: 
o Familiarity (Appendix K) 
o Liking rating (Appendix L) 
DEBRIEFING 
QUESTIONNAIRE 
▪ 
Aim guessing in an open-ended response format (Appendix M) 
▪ 
Questionnaire (Appendix M) 
ADDITIONAL 
MEASURES 
▪ 
Interoception preliminary survey1 (Appendix N) 
DEBRIEFING TEXT 
▪ 
Tell the participants what the study was about (Appendix O) 
DATA MANAGEMENT 
▪ 
The result files will contain: 
o Participant unique ID 
o Experimental condition participant is directed to 
o Amount of self-served food 
o Answers to questionnaires 
 
7. STATISTICAL ANALYSES 
All statistical analyses will be performed using SAS version 9.3 (SAS Institute, Inc., 2012 SAS® 9.3. 
Cary, NC). The level of significance will be set at p < 0.05 for the main and sensitivity analyses, p < 
0.01 for secondary analyses and p < 0.001 for exploratory analyses unless otherwise specified. Linear 
mixed models will be fitted with PROC MIXED. 
7.1. Variables description 
Primary outcome 
The main outcome variable is the total self-served energy (in kcal). 
Other outcomes: 
Derived from the debriefing questionnaire: 
1. Kcal influence (item 1): whether kcal content influences the quantity of self-served food; 
2. PACE influence (item 2): whether physical activity energy equivalent influences the quantity 
of self-served food. 
Answers to each item will be coded as: 1 = Strongly disagree; 2 = Disagree; 3 = Slightly disagree; 4 = 
Neutral; 5 = Slightly agree; 6 = Agree; 7 = Strongly agree. 
Independent variables 
SEP 
                                                          
1 These data are collected to inform a future study and will not be analysed as part of this study. 

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Highest educational qualification will be coded from 1 to 9: 1 = No formal qualifications; 2 = 1–3 
GCSEs; 3 = 4+ GCSEs; 4 = A level; 5 = Certificate of higher education (CertHE); 6 = Diploma of higher 
education (DipHE); 7 = Bachelor; 8 = Master’s degree; 9 = Doctorate, and as a binary variable as 
lower (values: 1, 2, 3, 4 ) or higher (values: 5, 6, 7, 8, 9). 
Years in higher education, as a continuous variable. 
Level of education (composite score): Assuming that highest educational qualification and years in 
higher education will be significantly correlated (tested using Pearson’s r), we will z-score the two 
variables and create an average of the two to form a level of education composite score. 
Equivalised household income: The OECD-modified equivalence scale will be used to adjust 
household income considering household size and composition [27]. Equivalised household income 
is calculated by dividing the after-tax household (including all the earner to the nearest £1000) by 
the sum of the equivalence value of all the household members (1 = first adult; 0.5 = additional adult 
or child >14 years old; 0.3 = child aged 0-13 years old). 
Subjective SEP: The measure of the Subjective Social Status using the MacArthur Scale will be coded 
from 1 (lower SSS) to 10 (higher SSS). 
Executive function measures 
Inhibition – Stroop task: The median reaction times (RTs) will be calculated for correct responses in 
incongruent and congruent trials. The interference effect will be calculated as the difference 
between the median RTs of the incongruent trials and the congruent trials. A larger interference 
score is indicative of poorer inhibition. RTs data are commonly skewed, reflecting lapses of attention 
or eye blinks during the task [28]. To resolve this, median will be used instead of means. Median is 
less affected by extreme scores than the mean and provides a better estimate of central tendency 
for skewed distributions [29], [30]. We will also calculate the proportion of correct responses in 
incongruent trials because this outcome has been previously linked to the frequency of fatty food 
consumption [31]. 
Working memory – backwards digit-span task: The two-error maximum length will be calculated. It 
is the last digit-span a participant gets correct before making two consecutive errors and the 
traditional measure of a participant’s backward digit span [32]. We will also calculate the maximum 
length i.e., the maximal backward digit span that a participant recalled correctly during all 14 trials. 
Familiarity 
When the answer to the question “Have you ever eaten this food?” will be ‘yes’, the food will be 
coded as familiar for a participant. 
Liking 
For each participant and each food a liking score from 0 to 100 will be recorded (anchors: not at all, 
extremely). 
Health motivation in food choices 
Both health and weight control motivation scores will be computed by averaging ratings for 
individual items in each dimension (health motivation: 6 items; weight control motivation: 4 items). 
They will range from 1 to 4: 1 = Not at all important; 2 = A little important; 3 = Moderately 
important; 4 = Very important. Cronbach’s alpha will be calculated as an indicator of internal 
consistency in order to compare our data with the original study that developed this measure [24]. 

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Other variables 
BMI will be calculated as weight (kg) / height (m2). BMI data will be trimmed for implausible values 
excluding weight for less than 30 kg and more than 250 kg, height for less than 145 cm and more 
than 3m, BMI < 14 or BMI > 48 [33], [34]. 
Physical activity level will be estimated based on IPAQ-SF answers as MET-minutes per week2: self-
reported physical activity in minutes*MET score [walking = 3.3, moderate intensity = 4.0, vigorous 
intensity = 8.0]*number of days [25]. 
Aim guessing: Participants who identify the aim of the study as being to examine the influence of 
kcal or PACE labelling on self-served food portion size will be coded as being aware of the study 
aims. Responses will be independently coded by two researchers, with discrepancies in coding 
decisions resolved by a third researcher. 
7.2. Missing data 
We do not anticipate missing data on the primary outcome and dependant variables because the 
online study will not allow missing answers. Data from participants who start but not finish the study 
will not be analysed. Submissions of participants who fail the attention checks or do not pass 
eligibility criteria will not be analysed. Any a posteriori withdrawal will be reported and reasons for 
withdrawal will be documented (e.g. incorrect answers, technical problems). 
7.3. Participant’s characteristics 
We will report the baseline characteristics overall and for participants of lower and higher education 
including gender, age, ethnic group, employment status, highest educational qualification, years in 
higher education, equivalised household income, subjective socioeconomic status, BMI, dieting 
status and physical activity in MET-minutes for vigorous-intensity activity, moderate-intensity 
activity, walking and in total. Continuous variables will be summarised using means and standard 
deviations and differences between the two groups will be tested using t-tests. Categorical variables 
will be summarised using counts and percentages and differences between the two groups will be 
tested using Chi-square tests. 
7.4. Familiarity and liking 
We will report the percentage of dishes that participants are familiar with and the average liking 
score across foods overall and for participants of lower and higher education. Differences in 
familiarity between the two groups will be tested using Chi-square tests and differences in liking 
using t-tests. 
7.5. Main analyses 
The primary aim of the statistical analyses will be to test the effect the labelling intervention and SEP 
on self-served energy. Secondary analyses will be run in order to investigate the role of potential 
mediators to explain the relationship SEP-self-served energy. The measure of SEP used in our main 
analyses will be the highest educational qualification (binary variable: lower vs. higher) because 
previous research showed that people of higher education were more likely to use nutrition labels 
[35], [36]. 
                                                          
2 MET-minutes: Metabolic Equivalent of Task of an activity × minutes performed. 

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Linear mixed effect models will be run in order to test the effect of the labels and of highest 
educational qualification on the self-served energy, with participants and dishes set as random 
effects to account for correlation between repeated measures by the same participant and across 
the different food items. The main model will test the effect of the labelling intervention (four levels: 
kcal labelling, PACE labelling, kcal and PACE labelling, no labelling), highest educational qualification 
(two levels: lower, higher) and the interaction between labelling intervention and highest 
educational qualification. If the interaction is significant, analyses will be stratified by highest 
educational qualification (lower and higher) and two linear mixed models will be fitted to examine 
the effect of the labelling intervention on self-served energy. 
If there is a main effect of the labelling intervention in one of the above linear mixed models we will 
follow up this main effect by conducting the following pairwise comparisons: 
- 
Self-served energy in each of the three labelling conditions compared to no labelling 
condition: 
o No labelling vs. kcal labelling 
o No labelling vs. PACE labelling 
o No labelling vs. kcal and PACE labelling combined 
- 
Self-served energy in the combined labelling condition compared to single labelling 
conditions 
o Kcal and PACE labelling combined vs. kcal labelling 
o Kcal and PACE labelling combined vs. PACE labelling 
- 
Self-served energy in one single labelling condition compared to the other single labelling 
condition: 
o Kcal labelling vs. PACE labelling 
We will apply a Bonferroni correction to the level of significance based on the number of pairwise 
comparisons made (e.g., 12 comparisons: 0.05/12=0.004). 
7.6. Sensitivity analyses 
We will conduct sensitivity analyses to examine whether the pattern of results from the main 
analyses differ when: 
- 
excluding the aim guessers from the main analyses, or if more than 20% of participants 
guess the aim of the study, including an ‘aim guessing’ variable (two levels: yes, no) as a 
covariate in the main model; 
- 
substituting highest educational qualification by level of education (composite score) in the 
main model; 
- 
including hunger and liking as covariates in the main model as these two variables are likely 
to influence how much one serves oneself of a dish; 
- 
excluding any dish that is familiar to less than 50% of participants or that is scored < 50 in 
liking on average (mid-way of the scale) to examine whether results are consistent when 
only well liked and familiar foods are used. 
We will report whether sensitivity analyses result in deviations from the pattern of significance to 
the main analyses (i.e., any significant differences between conditions becoming not significant, and 
vice versa). 
7.7. Secondary analyses 
To account for multiple testing the alpha level for secondary analyses will be set at p = 0.01. 

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Alternative measures of SEP 
The main analyses will be repeated using alternative measures of SEP to investigate whether 
different measures lead to the same pattern of results. Highest educational qualification will be 
substituted by 1/ equivalised income, and 2/ SSS. 
Moderated mediation analyses 
We will report and compare the measures of inhibition, working memory, healthiness and weight 
control motivation in food choices overall and for participants of lower vs. higher education level 
using means, standard deviations and t-tests. 
If the main analyses suggest that highest educational qualification moderates the effect of labelling 
intervention (i.e., the labelling intervention*highest educational qualification is significant), 
moderated mediation analyses will be performed in order to explain the different effect of labelling 
intervention in participants of lower vs. higher education level. We will test as mediators the 
measures of inhibition, working memory, healthiness and weight control motivation in food choices 
only if we find individual differences on these measures between participants of lower and higher 
education level. Moderated mediation analyses will examine the extent to which they mediate the 
effect of highest educational qualification on self-served energy in each labelling condition (kcal 
labelling, PACE labelling, kcal and PACE labelling, no labelling). 
Conceptual diagram: 
 
 
 
Statistical diagram: 
 
 
 
Conditional indirect effect of highest educational qualification on self-served energy through a 
mediator M will be calculated as a*(b1+ b2*labelling). 
The moderated mediation will be tested by estimating the conditional indirect effect of highest 
educational qualification through M for kcal labelling, PACE labelling, kcal and PACE labelling, no 
labelling conditions and testing the conditional indirect effect for those conditions using bias-
corrected bootstrap. We will use the PROCESS macro (Model 15) on SAS version 9.3 that provides 
asymmetric bias-corrected bootstrap confidence intervals for inference about the conditional 
indirect effects using 5,000 bootstrap samples [37]. Moderated mediation will be tested by 
determining whether or not the confidence interval for the difference between conditional indirect 
effects for kcal labelling, PACE labelling, kcal and PACE labelling versus no labelling contains zero. 
7.8. Exploratory analyses 
To account for multiple testing the alpha level for exploratory analyses will be set at p = 0.001. 
Analysis of potential moderators of the effect of the labelling intervention 

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We will explore if the other variables we will measure could individually moderate the effect of the 
labelling intervention on self-served energy independently of SEP. We will substitute highest 
educational qualification in the main analyses by measures of inhibition, working memory, 
healthiness and weight control motivation in food choices, physical activity in MET-minutes for 
walking and in total. 
Debriefing questionnaire 
Answers to all the items of the debriefing questionnaire will be described as mean ± SD overall and 
for participants of lower and higher education. Differences between the two groups will be tested 
using t-tests. Two ANOVAs will be run to test the effect of the labelling intervention and of highest 
educational qualification on the first two items: kcal influence and PACE influence. 
7.9. Sample size 
A meta-analysis of six studies investigating the impact of kcal labelling on energy consumed from a 
single food did not demonstrate a statistically significant effect [11]. However the designs of these 
studies were different from the present study: the food options were mainly snacks (only one study 
offered to consume main meals [38]) and participants were not aware of the amount of kcal they 
actually consumed (the label was placed on the container or packaging, adjacent to the food, or 
presented on a display board). In our design, we expect a significant effect of kcal labelling with a 
reduction of 8.4% of self-served energy per meal may occur, which is the effect size found in a meta-
analysis investigating the impact of kcal labelling on energy consumed during a meal with a range of 
available food options – i.e., the most similar design to the present study. The most up to date 
evidence of an effect of PACE labelling on energy consumed from foods/drinks is a meta-analysis of 
two studies and showed a significant reduction of 14.4%. Due to the small number of participants 
included in this meta-analysis, we conservatory powered our study to be able to detect an 8% 
reduction for both type of labels (kcal, PACE or kcal and PACE). 
We will run a two-level mixed model including 18 trials (level 1) per participant (level 2) and 
compare self-served energy in each of the four trial arms (control, kcal labelling, PACE labelling, kcal 
and PACE labelling). We estimate SD of 300 kcal for self-served energy at level 1 and level 2 based on 
average SD of energy consumed during experimental meals [11]. A sample size of 1,600 participants 
with α = 0.05 will allow to detect a 8% energy reduction between any of the four groups at power = 
0.80. It will also allow to detect a small effect (f=0.07) of the interaction between the interventions 
and higher educational qualification education at power = 0.80 (MLPowSim) [39]. 
In a previous study we conducted at virtual fast food restaurants [40], we found small-to-medium 
correlation between level of education and healthiness motivation (r=0.17) and small-to-medium 
correlation between healthiness motivation and kcal ordered (r=-0.25). Because evidence of a 
relationship between SEP and physical activity is mixed [41], we hypothesize small-to-medium 
correlation. Empirical estimates of sample sizes needed for 0.8 power in mediation analyses indicate 
that samples of ≈ 380 are sufficient to detect mediation through pathways that are small and small-
to-medium in statistical size using bias-corrected bootstrap tests [42]. Thus, a sample of 1,600 
participants (i.e., 400 per experimental condition) would allow for adequate power in our planned 
moderated mediation analysis. 
We will recruit a sample of 1,800 participants (who consent to take part in the study) to account for 
potential data loss due to dropouts and failed quality controls (approx. 10%) resulting in a minimum 
sample of 1,600 participants for analyses. However, if we experience a greater loss of data than 

07/04/2020 pre-registered 
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expected, we will continue to recruit participants until we achieve the required sample size of 1,600 
participants. 
8. REFERENCES 
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2019. 
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M. Pigeyre, J. Rousseaux, P. Trouiller, J. Dumont, L. Goumidi, D. Bonte, M. P. Dumont, A. 
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Obes., vol. 40, no. 11, pp. 1794–1801, 2016. 
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Bueno-De-Mesquita, and J. W. J. Beulens, “The contribution of diet and lifestyle to 
socioeconomic inequalities in cardiovascular morbidity and mortality,” Int. J. Cardiol., vol. 
168, no. 6, pp. 5190–5195, 2013. 
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“Socioeconomic Status and Health. The Challenge of the Gradient,” Socioecon. Status Heal., 
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[6] 
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World Heal. Organ Tech Rep Ser, vol. 916, pp. 1–149, 2003. 
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N. T. Burkert, É. Rásky, F. Großschädl, J. Muckenhuber, and W. Freidl, “The Influence of 
Socioeconomic Factors on Health Parameters in Overweight and Obese Adults,” PLoS One, 
vol. 8, no. 6, pp. 1–8, 2013. 
[8] 
M. I. Cardel, S. L. Johnson, J. Beck, E. Dhurandhar, A. D. Keita, A. C. Tomczik, G. Pavela, T. Huo, 
D. M. Janicke, K. Muller, P. K. Piff, J. C. Peters, J. O. Hill, and D. B. Allison, “The effects of 
experimentally manipulated social status on acute eating behavior: A randomized, crossover 
pilot study,” Physiol. Behav., vol. 162, pp. 93–101, 2016. 
[9] 
A. Y. Sim, E. X. Lim, C. G. Forde, and B. K. Cheon, “Personal relative deprivation increases self-
selected portion sizes and food intake,” Appetite, vol. 121, pp. 268–274, 2018. 
[10] 
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C. K. Martin, D. B. Allison, and E. J. Dhurandhar, “Subjective social status is associated with 
compensation for large meals – A prospective pilot study,” Appetite, vol. 132, no. July 2018, 
pp. 249–256, 2019. 
[11] 
R. A. Crockett, S. E. King, T. M. Marteau, A. T. Prevost, G. Bignardi, N. W. Roberts, B. Stubbs, 
G. J. Hollands, and S. A. Jebb, “Nutritional labelling for healthier food or non-alcoholic drink 
purchasing and consumption,” Cochrane Database Syst. Rev., vol. 2, p. CD009315, 2018. 
[12] 
D. Sarink, A. Peeters, R. Freak-Poli, A. Beauchamp, J. Woods, K. Ball, and K. Backholer, “The 
impact of menu energy labelling across socioeconomic groups: A systematic review,” 
Appetite, vol. 99, pp. 59–75, 2016. 

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15 
 
[13] 
A. J. Daley, E. McGee, S. Bayliss, A. Coombe, and H. M. Parretti, “Effects of physical activity 
calorie equivalent food labelling to reduce food selection and consumption: Systematic 
review and meta-analysis of randomised controlled studies,” J. Epidemiol. Community Health, 
pp. 1–7, 2019. 
[14] 
S. Reale and S. W. Flint, “Menu labelling and food choice in obese adults: A feasibility study,” 
BMC Obes., vol. 3, no. 1, pp. 1–9, 2016. 
[15] 
R. Antonelli and A. J. Viera, “Potential effect of physical activity calorie equivalent (PACE) 
labeling on adult fast food ordering and exercise,” PLoS One, vol. 10, no. 7, pp. 1–11, 2015. 
[16] 
H. Konttinen, S. Sarlio-Lähteenkorva, K. Silventoinen, S. Männistö, and A. Haukkala, “Socio-
economic disparities in the consumption of vegetables, fruit and energy-dense foods: The 
role of motive priorities,” Public Health Nutr., vol. 16, no. 5, pp. 873–882, 2012. 
[17] 
L. Dubé and I. Cantin, “Promoting health or promoting pleasure? A contingency approach to 
the effect of informational and emotional appeals on food liking and consumption.,” 
Appetite, vol. 35, no. 3, pp. 251–62, Dec. 2000. 
[18] 
HESA, “Higher Education Student Statistics: UK, 2017/18,” Statistical Bulletin, SB252, 2019. 
[Online]. Available: https://www.hesa.ac.uk/news/17-01-2019/sb252-higher-education-
student-statistics. [Accessed: 11-Jun-2019]. 
[19] 
P. G. Curran, “Methods for the detection of carelessly invalid responses in survey data,” J. 
Exp. Soc. Psychol., vol. 66, pp. 4–19, 2016. 
[20] 
J. L. Huang, P. G. Curran, J. Keeney, E. M. Poposki, and R. P. DeShon, “Detecting and Deterring 
Insufficient Effort Responding to Surveys,” J. Bus. Psychol., vol. 27, no. 1, pp. 99–114, 2012. 
[21] 
V. Whitelock, S. Higgs, J. M. Brunstrom, J. C. G. Halford, and E. Robinson, “No effect of 
focused attention whilst eating on later snack food intake: Two laboratory experiments,” 
Appetite, vol. 128, no. April, pp. 188–196, 2018. 
[22] 
J. J. Swartz, S. Dowray, D. Braxton, P. Mihas, and A. J. Viera, “Simplifying healthful choices: A 
qualitative study of a physical activity based nutrition label format,” Nutr. J., vol. 12, no. 1, pp. 
1–9, 2013. 
[23] 
N. E. Adler, E. Epel, G. Casterllazzo, and J. Ickovics, “Relationship of subjective and objective 
social status with psychological and physical health in healthy white women,” Heal. Psychol., 
vol. 19, no. 6, pp. 586–592, 2000. 
[24] 
A. Steptoe, T. M. Pollard, and J. Wardle, “Development of a Measure of the Motives 
Underlying the Selection of Food: the ‘Food Choice Questionnaire,’” Appetite, vol. 25, pp. 
267–284, 1995. 
[25] 
C. L. Craig, A. L. Marshall, M. Sjöström, A. E. Bauman, M. L. Booth, B. E. Ainsworth, M. Pratt, 
U. Ekelund, A. Yngve, J. F. Sallis, and P. Oja, “International physical activity questionnaire: 12-
Country reliability and validity,” Med. Sci. Sports Exerc., vol. 35, no. 8, pp. 1381–1395, 2003. 
[26] 
Public Health England, “Calorie reduction : The scope and ambition for action,” 2018. 
[27] 
Office for National Statistics, “Chapter 3: Equivalised income,” in Compendium: Family 
Spending in the UK, 2015. 
[28] 
A. Heathcote, S. Popiel, and D. Mewhort, “Analysis of Response Time Distributions : An 
Example Using the Stroop Task,” vol. 109, no. 2, pp. 340–347, 1991. 
[29] 
G. A. Rousselet and R. R. Wilcox, “Reaction times and other skewed distributions: problems 

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with the mean and the median,” Meta-Psychology, vol. in press, 2019. 
[30] 
R. Ratcliff, “Methods for dealing with RT outliers,” Psychol. Bull., vol. 114, no. 3, pp. 510–532, 
1993. 
[31] 
P. A. Hall, “Executive control resources and frequency of fatty food consumption: Findings 
from an age-stratified community sample,” Heal. Psychol., vol. 31, no. 2, pp. 235–241, 2012. 
[32] 
D. L. Woods, M. M. Kishiyama, E. W. Yund, T. J. Herron, B. Edwards, R. F. Hink, and B. Reed, 
“Improving digit span assessment,” vol. 33, no. 1, pp. 1–11, 2012. 
[33] 
Y. Miller, “Recommendations for the truncation of Body Mass Index in population data,” NSW 
Centre for Physical Activity and Health, no. September. pp. 1–16, 2003. 
[34] 
R. Hardy, J. Johnson, and A. Park, “Harmonised height, weight and BMI user guide,” no. July. 
Closer. Cohort & Longitudinal Studies Enhancement Resources, pp. 1–17, 2016. 
[35] 
G. Cowburn and L. Stockley, “Consumer understanding and use of nutrition labelling: a 
systematic review,” Public Health Nutr., vol. 8, no. 01, 2008. 
[36] 
A. Breck, J. Cantor, O. Martinez, and B. Elbel, “Who reports noticing and using calorie 
information posted on fast food restaurant menus?,” Appetite, vol. 81, pp. 30–36, 2014. 
[37] 
A. F. Hayes, PROCESS: A versatile computational tool for observed variable mediation, 
moderation, and conditional process modeling, University. KS, 2012. 
[38] 
T. V. E. Kral, L. S. Roe, and B. J. Rolls, “Does nutrition information about the energy density of 
meals affect food intake in normal-weight women?,” Appetite, vol. 39, no. 2, pp. 137–145, 
2002. 
[39] 
W. J. Browne, M. G. Lahi, and R. M. a Parker, “A Guide to Sample Size Calculations for 
Random Effect Models via Simulation and the MLPowSim Software Package School of Clinical 
Veterinary Sciences , University of Bristol * Tarbiat Modares University , Iran This draft – 
March 2009,” no. March. 2009. 
[40] 
L. Marty, A. Jones, and E. Robinson, “Socioeconomic position and the impact of increasing 
availability of lower energy meals vs. menu energy labelling on food choice: Two randomized 
controlled trials in a virtual fast-food restaurant,” Int. J. Behav. Nutr. Phys. Act., vol. 17, no. 1, 
pp. 1–11, 2020. 
[41] 
C. Gidlow, L. H. Johnston, D. Crone, N. Ellis, and D. James, “A systematic review of the 
relationship between socio-economic position and physical activity,” Health Educ. J., vol. 65, 
no. 4, pp. 338–367, 2006. 
[42] 
M. S. Fritz and D. P. Mackinnon, “Required Sample Size to Detect the Mediated Effect,” 
Psychol. Sci., vol. 18, no. 3, pp. 233–239, 2007. 
 
 
 

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9. APPENDIX A: FOOD STIMULI DESCRIPTION 
 
FOOD 
1st picture 
20 kcal 
25th picture 
500 kcal 
Last (50th) picture 
1000 kcal 
Beef in black beans sauce 
with rice 
130 kcal/100g 
Beef 8.7 g 
Rice 6.7 g 
Beef 217.6 g 
Rice 167 g 
Beef 435.2 g 
Rice 334.0 g 
Beef stew with dumplings 
167 kcal/100g 
Beef 8.07 g 
Dumplings 3.9 g 
Beef 201.77 g 
Dumplings 97.6 g 
Beef 403.53 g 
Dumplings 195.27 g 
Chicken and bacon pasta 
139 kcal/100g 
14.4 g 
359.7 g 
719.4 g 
Chicken, chips and beans 
225 kcal/100g 
Chicken 3.1 g 
Chips 4.2 g 
Beans 2.84 g 
Chicken 80.5 g 
Chips 108.9 g 
Beans 74.05 g 
Chicken 154.8 g 
Chips 209.5 g 
Beans 142.41 g 
Chicken korma with rice 
154 kcal/100g 
Chicken 7.1 g 
Rice 5.9 g 
Chicken 177.3 g 
Rice 147.4 g 
Chicken 354.5 g 
Rice 294.8 g 
Chicken salad 
98.31 kcal/100g 
Cucumber 7.3 g 
Salad 5.6 g 
Chicken 4.4 g 
Croutons 1.4 g 
Dressing 1.2 g 
Parmesan 0.5 g 
Cucumber 182.3 g 
Salad 129.5 g 
Chicken 100.8 g 
Croutons 31.7 g 
Dressing 27.3 g 
Parmesan 10.8 g 
Cucumber 364.5 g 
Salad 281.6 g 
Chicken 219 g 
Croutons 68.8 g 
Dressing 59.4 g 
Parmesan 23.5 g 
Cous cous and salad 
179.38 kcal/100g 
Cous cous 10.2 g 
Salad 0.9 g 
Cous cous 255.3 g 
Salad 23.4 g 
Cous cous 510.6 g 
Salad 46.8 g 
Fish, chips and peas 
171.56 kcal/100g 
Fish 3.25 g 
Chips 5.85 g 
Peas 2.54 g 
Fish 81.44 g 
Chips 146.25 g 
Peas 63.74 g 
Fish 162.88 g 
Chips 292.5 g 
Peas 127.50 g 
Grilled white fish (41.24%) 
with tomato and bean salad 
75.68 kcal/100g 
Fish (cooked) 10.9 g 
Salad 15.5 g 
Fish (cooked) 272.5 g 
Salad 388.1 g 
Fish (cooked) 545 g 
Salad 776.3 g 
Ham and mushroom 
carbonara 
199 kcal/100g 
10.1 g 
251.3 g 
 
502.5 g 
 
Lasagne and peas (9.25%) 
144.23 kcal/100g 
Lasagne 11.9 g 
Peas 2.7 g 
Lasagne 310.5 g 
Peas 70.73 g 
Lasagne 597 g 
Peas 136 g 
Macaroni cheese 
183 kcal/100g 
10.9 g 
273.2g 
546.4 g 
Mushroom risotto 
130 kcal/100g 
15.4 g 
384.6 g 
769.29 g 
Peperoni pizza 
272 kcal/100g 
7.35 g 
183.82 g 
367.64 g 
Sausage (55.93%), mashed 
potatoes (33.55%) and peas 
(10.52%) 
163.417 kcal/100g 
Sausage 4.7 g 
Potatoes 9.7 g 
Peas 3.09 g 
 
Sausage 122.2 g 
Potatoes 252.8 g 
Peas 80.44 g 
Sausage 235 g 
Potatoes 486.2 g 
Peas 154.7 g 
Spaghetti Bolognese 
141 kcal/100g 
14.1 g 
354.61 g 
709.2 g 
Spinach & Ricotta tortellini 
with tomato sauce 
316 kcal/100g 
 
15.7 g (cooked) 
 
393.4 g (cooked) 
 
786.9 g (cooked) 
Vegetable biryani 
127 kcal/100g 
15.7 g 
393.7 g 
787.4 g 
10.  
 
 

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11. APPENDIX B: TARGETED AUDIENCE (PROLIFIC WEBSITE) 
 
1. Age 
o 18 years old or above 
 
2. Current country of residence 
o UK 
 
3. Fluent language 
o English 
 
4. Diet restriction 
o None 
 
5. Gender 
50% of participants 
o Male 
50% of participants 
o Female 
 
6. Students 
96.5% of participants 
o No 
3.5% of participants 
o Yes 
 
7. Highest education level completed 
50% of participants 
o No formal qualifications 
o Secondary education (e.g. GED/GCSE) 
o High school diploma/A-levels 
50% of participants 
o Technical/community college 
o Undergraduate degree (BA/BSc/other) 
o Graduate degree (MA/MSc/MPhil/other) 
o Doctorate degree (PhD/other) 
 
 
 

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12. APPENDIX C: RECRUITMENT TEXT 
“This is a study examining eating behaviour. You will be asked to choose how much of several dishes 
you would serve yourself if you were eating it as a main meal and to fill some questionnaires in about 
yourself. 
Overall, the study will take about 25 minutes. 
If you would like to take part, please make sure that: 
- You have 25 minutes to complete this study, it must be taken in one sitting and you cannot exit and 
return to the study. 
- You read the instructions carefully and answer the questions as accurately as possible. 
- You agree to install a plugin to run the tasks. Instructions will be provided for how to install and 
uninstall the plugin. 
Failure to comply with these instructions may result in your submission being rejected. Attention 
checks have been included, failing them will result in your submission being rejected.” 
 
 

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13. APPENDIX D: INFORMATION PAGE 
 
 
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. We would like to stress that 
you should only agree to take part if you want to. 
 
What is the purpose of the study? 
The purpose of the study is to understand eating behaviours. 
  
Why have I been chosen to take part? 
 
We are recruiting volunteers who fulfil the following criteria: 
1. Aged ≥ 18 years 
2. Fluent English speaker 
3. Reside in the UK 
4. Do not have any dietary restriction 
 
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. 
 
What will happen if I take part? 
You will provide some information about yourself (e.g., age, gender), before then 
completing a portion selection task and filling in questionnaires about eating and 
bodily sensations. So that your awareness of the study hypotheses does not affect 
your behaviour in the study we provide more detailed information about the study 
aims at the end of the study. If you feel uncomfortable about this then you are 
free not to participate in this study. Overall the study will take 25 minutes. 
 
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 below. 
How will my data be collected? 
Through an online questionnaire. 

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Are there any risks in taking part? 
There are no anticipated risks to you if you take part in the study. 
 
Are there any benefits in taking part? 
There are no direct benefits, other than the small monetary payment. 
 
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. 
 
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. 
How will my data be stored? 
On a password protected computer server. 
How long will my data be stored for? 
Your personal data 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).  

07/04/2020 pre-registered 
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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 Dr Lucile Marty (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. 
 
Who can I contact if I have further questions? 
Please contact the principle investigator:  
Dr Lucile Marty 
2.41b, Eleanor Rathbone Building 
Bedford Street South 
University of Liverpool, 
Liverpool,  
L69 7ZA, 
UK 
email: lucile.marty@liverpool.ac.uk 
 
or the data protection officer: 
Victoria Heath 
The Foundation Building, 
765 Brownlow Hill, 
University of Liverpool, 
Liverpool, 
L69 7ZX, 
UK, 
email: V.Heath@liverpool.ac.uk  
 
I confirm I have read the information sheet 
 
o Yes 
 
 

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14. APPENDIX E: CONSENT PAGE 
 
 
I confirm that I have read and have understood the information sheet for the 
study. I have had the opportunity to consider the information, ask questions and 
have had these answered satisfactorily. 
 
I understand that taking part in the study involves completing online tasks and 
questionnaires. 
 
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. 
 
I understand that the information I provide is for research purposes 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 will never be shared beyond the study team. 
 
I understand that shortly after completing the study, researchers will keep my 
personal data 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. 
 
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. 
 
I provide my consent as a legal basis for the processing of my data as detailed previously, 
including the purposes of data processing, recipients of data and the right to withdraw my 
data. 
I agree and consent to take part in the above study 
 

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o Yes 
 
 

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15. APPENDIX F: REQUIREMENTS 
 
1. .Are you a fluent English speaker? 
o Yes 
o No 
 
If answer “No”, participant cannot take part of the study 
 
2. Do you currently reside in the UK? 
o Yes 
o No 
 
If answer “No”, participant cannot take part of the study 
 
3. Do you have any dietary restriction? 
 None 
 Vegetarian 
 Vegan 
 Gluten-free 
 Sugar-free 
 Diary/lactose-free 
 Food allergy (e.g. milk, eggs, nut, wheat, fish, etc.) 
 Other dietary restriction 
 
If answer other than “None”, participant cannot take part of the study 
 
If the participant cannot take part in the study, the following message will appear on the 
screen: 
 
“Sorry, you are ineligible to take part in this study. 
Please, go back to your Prolific page, return your submission and update your personal 
information.” 
 
 

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16. APPENDIX G: BASELINE QUESTIONNAIRE 
 
1. Gender 
o Male 
o Female 
o Other 
 
2. Age 
o _ _ (free text; range of 18-99) 
 
3. Ethnicity 
o White 
o Black 
o Asian 
o Mixed 
o Other 
 
4. What is your current employment status? 
o Full or part-time 
o Student 
o Retired 
o Temporary or permanently sick or disabled 
o Looking after home/family 
o Other unemployed 
 
5. What is your highest educational qualification? If you are a student please select the 
diploma being studied for. 
o No qualification 
o 1-3 GCSEs 
o 4+ GCSEs 
o A level 
o CertHE 
o DipHE 
o Higher education or Bachelor’s degree 
o Post-Graduate degree  
o Doctoral or professional degree 
 
6. After leaving school (i.e. at 16 years old), how many further years of higher education (i.e. 
a formal course) did you study for? 
Examples: 
If you left school and did not go on to study further in higher education, your answer would be 0. 
If you left school and then studied for two years for A levels, your answer would be 2. 
If you completed A levels over two years and then also studied for a three-year undergraduate degree, 
your answer would be 5. 
o _ _ (free text) 
 
7. What is your annual household income (after tax), including all earners in your household, 
in GBP (to the nearest £1000)? 

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£_ _ _ _ _ _ (free text; range 0-999,999) 
 
8. How many adult(s) or child(ren) aged 14 and over live at your house, including you? 
_ _ (free text; range of 1-20) 
 
9. How many child(ren) aged under 14 live at your house, including you? 
_ _ (free text; range of 1-20) 
 
10. This is an attention check. How many times have you visited the planet Mars? 
o Several times 
o Just once 
o Never 
 
11. Think of a ladder (see the image below) as representing where people stand in society. At 
the top of the ladder are the people who are best off—those who have the most money, 
most education and the best jobs. At the bottom are the people who are worst off—who 
have the least money, least education and the worst jobs or no job. The higher up you are 
on this ladder, the closer you are to people at the very top and the lower you are, the 
closer you are to the bottom. Where would you place yourself on the ladder?  
 
Choose the number whose position best represents where you would be on this ladder: 
○ 1 
○ 2 
○ 3 
○ 4 
○ 5 
○ 6 
○ 7 
○ 8 
○ 9 
○ 10 
 
12. Are you currently dieting? 
o Yes 
o No 
 

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13. Weight 
Select the unit: 
o kg 
o st and lb 
_ _ _ 
 
14. Height 
Select the unit: 
o cm 
o ft and in 
_ _ _ 
 
15. How hungry do you feel? 
__________________________________________________________________________________ 
0 
 
 
 
 
 
 
 
 
 
 
 
100 
Not at all hungry  
 
 
 
 
 
 
 
    Extremely hungry 
 
 
 

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17. APPENDIX H: MEAL CHOICE TASK INSTRUCTIONS 
Kcal-/PACE- group 
Before the task begins 
 
Portion selection task 
 
 
In this task, you will be shown pictures of 18 different dishes. For each dish, you will be asked to decide 
how much you would like to eat as if you were eating it as main meal. 
 
You can change the quantity using the arrow keys on your keyboard: 
- tap on the right arrow to increase the quantity, on the left one to decrease the quantity 
- use the space bar to select the portion size you would like to eat. 
 
Before you make your choice, take the time to explore the full range of portion sizes. 
You need to increase the amount of food at least once to be able to select a portion and continue. 
 
Tap the spacebar to start. 
 

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During the task 
 
 
 
 
 

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Kcal+/PACE- group: 
Before the task begins 
Portion selection task 
 
In this task, you will be shown pictures of 18 different dishes. For each dish, you will be asked to 
decide how much you would like to eat as if you were eating it as main meal. For each portion, the 
label on the left will show you the calorie content. 
 
You can change the quantity using the arrow keys on your keyboard: 
- tap on the right arrow to increase the quantity, on the left one to decrease the quantity 
- use the space bar to select the portion size you would like to eat. 
 
Before you make your choice, take the time to explore the full range of portion sizes. 
You need to increase the amount of food at least once to be able to select a portion and continue. 
 
Tap the spacebar to start. 
 
 
 

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During the task 
 
 
On average women need 2,000 kcal per day and men need 2,500 kcal per day. 
 
 
 

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Kcal-/PACE+ group: 
Before the task begins 
Portion selection task 
 
In this task, you will be shown pictures of 18 different dishes. For each dish, you will be asked to 
decide how much you would like to eat as if you were eating it as main meal. For each portion, the 
label on the left will show you the physical activity calorie equivalent, as the number of minutes of 
walking needed to burn off the calories in the meal. 
 
You can change the quantity using the arrow keys on your keyboard: 
- tap on the right arrow to increase the quantity, on the left one to decrease the quantity 
- use the space bar to select the portion size you would like to eat. 
 
Before you make your choice, take the time to explore the full range of portion sizes. 
You need to increase the amount of food at least once to be able to select a portion and continue. 
 
Tap the spacebar to start. 
 
  
 
 

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During the task 
 
According to physical activity recommendations, adults should aim to take part in at least 150 
minutes of moderate intensity physical activity per week (brisk walk, swim, cycle). 
 
 
 
 
 
 
 
 

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Kcal+/PACE+ group: 
Before the task begins 
Portion selection task 
 
 
In this task, you will be shown pictures of 18 different dishes. For each dish, you will be asked to 
decide how much you would like to eat as if you were eating it as main meal. For each portion, the 
label on the left will show you the calorie content and the physical activity calorie equivalent, as the 
number of minutes of walking needed to burn off the calories in the meal. 
 
You can change the quantity using the arrow keys on your keyboard: 
- tap on the right arrow to increase the quantity, on the left one to decrease the quantity 
- use the space bar to select the portion size you would like to eat. 
 
Before you make your choice, take the time to explore the full range of portion sizes. 
You need to increase the amount of food at least once to be able to select a portion and continue. 
 
Tap the spacebar to start. 
 

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During the task 
On average women need 2,000 kcal per day and men need 2,500 kcal per day. 
According to physical activity recommendations, adults should aim to take part in at least 150 
minutes of moderate intensity physical activity per week (brisk walk, swim, cycle). 
 
 
 

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18. APPENDIX I: HEALTH AND WEIGHT CONTROL FOOD CHOICE MOTIVES 
Instruction: “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… 
(items will be showed in randomised order) 
 
 
 
Not at all 
important 
1 
A little 
important 
2 
Moderately 
important 
3 
Very 
important 
4 
Health 
1. 
contains a lot of vitamins and minerals 
o 
 
o 
 
o 
 
o 
 
2. 
keeps me healthy 
o 
 
o 
 
o 
 
o 
 
3. 
is nutritious 
o 
 
o 
 
o 
 
o 
 
4. 
is high in protein 
o 
 
o 
 
o 
 
o 
 
5. 
is good for my skin/teeth/hair/nails etc. 
o 
 
o 
 
o 
 
o 
 
6. 
is high in fibre and roughage 
o 
 
o 
 
o 
 
o 
 
Weight control 
7. 
is low in calories 
o 
 
o 
 
o 
 
o 
 
8. 
helps me control my weight 
o 
 
o 
 
o 
 
o 
 
9. 
is low in fat 
o 
 
o 
 
o 
 
o 
 
10. 
This is an attention check. Please choose 
the answer (2) ‘A little important’ 
o 
 
o 
 
o 
 
o 
 
 
 
 

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19. APPENDIX J: INTERNATIONAL PHYSICAL ACTIVITY QUESTIONNAIRE 
Instruction: “Think about a usual week and answer to the following questions. 
Please answer each question even if you do not consider yourself to be an active person. Think about 
the activities you do at work, as part of your house and yard work, to get from place to place and in 
your spare time for recreation, exercise or sport.” 
 
“Vigorous physical activities refer to activities that take hard physical effort and make you breathe 
much harder than normal. Think only about those physical activities that you usually do for at least 
10 minutes at a time.” 
 
1. 
During a usual week, on how many days do you do vigorous physical activities like heavy 
lifting, digging, aerobics, or fast bicycling?  
_ _ _ _ days per week  
 
2. 
How much time do you usually spend doing vigorous physical activities on one of those days?
 
If you answered 0 above, enter 0 here. 
_ _ _ _ minutes per day 
 
Think about all the moderate activities that you do during a usual week. Moderate activities refer to 
activities that take moderate physical effort and make you breathe somewhat harder than normal.  
Think only about those physical activities that you did for at least 10 minutes at a time. 
 
3. 
During a usual week, on how many days do you do moderate physical activities like carrying 
light loads, bicycling at a regular pace, or doubles tennis?  Do not include walking. 
_ _ _ _ days per week 
 
4. 
How much time do you usually spend doing moderate physical activities on one of those 
days? If you answered 0 above, enter 0 here. 
_ _ _ _ minutes per day 
 
Think about the time you spent walking during a usual week. This includes at work and at home, 
walking to travel from place to place, and any other walking that you have done solely for recreation, 
sport, exercise, or leisure. 
 
5. 
During a usual week, on how many days do you walk for at least 10 minutes at a time?   

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_ _ _ _ days per week 
 
6. 
How much time do you usually spend walking on one of those days? 
If you answered 0 above, enter 0 here. 
_ _ _ _ minutes per day 
 
Think about the time you spent sitting on weekdays during a usual week. Include time spent at work, 
at home, while doing course work and during leisure time. This may include time spent sitting at a 
desk, visiting friends, reading, or sitting or lying down to watch television. 
 
7. 
During a usual week, on how many days do you spend sitting on a week day? 
 
_ _ _ _ minutes per day 
 
 
 

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20. APPENDIX K: FAMILIARITY 
 
Instructions:  
 
“In this task, you will see 18 pictures of dishes. For each dish, you will be asked whether you have 
ever eaten this food and how much you like it. If you have never eaten a specific dish before, think 
about a similar food you have already tried and rate how much you think you would like it.” 
 
Questionnaire: 
 
1. Have you ever eaten this food before?  
 
 
o  
o  
Yes 
 No 
 
 
2. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 
 
3. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 
 
 
4. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 
 
5. Have you ever eaten this food before? 
 
 
 
o  
o  
Yes 
 No 
 
 
6. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 

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7. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 
 
8. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 
 
9. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 
 
10. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 
 
11. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 
 
12. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 
 
13. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 
 
 
14. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 
 

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15. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 
 
 
16. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 
 
 
 
 
 
17. Have you ever eaten this food before? 
 
 
o  
o  
Yes 
 No 
 
 
18. Have you ever eaten this food before? 
  
 
o  
o  
Yes 
 No 
 
 
 
 

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21. APPENDIX L: LIKING 
For each dish: 
 
 
I like this dish 
_________________________________________________________________________________ 
0 
 
 
 
 
 
 
 
 
 
 
 
100 
Not at all 
 
 
 
 
 
 
 
 
 
    Extremely 
 
 
 

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22. APPENDIX M: DEBRIEFING 
Aim guessing: 
What do you think we were expecting to find in this study? 
[Free text] 
Questionnaire: 
The questions 3, 4, 5, 6 will be randomised in order. 
1. The quantity I served myself for each dish was influenced by how many calories I thought were 
in the dishes. 
 
o  
o  
o  
o  
o  
o  
o  
Strongly 
disagree 
Disagree 
Slightly 
disagree 
Neither 
agree or 
disagree 
Slightly 
agree 
Agree 
Strongly 
agree 
 
2. The quantity I served myself for each dish was influenced by how much physical activity I 
thought I would have to do to burn off the calories that were in the dishes. 
 
o  
o  
o  
o  
o  
o  
o  
Strongly 
disagree 
Disagree 
Slightly 
disagree 
Neither 
agree or 
disagree 
Slightly 
agree 
Agree 
Strongly 
agree 
 
3. On a typical day, knowing how many calories are in my meals would influence how much I eat. 
 
o  
o  
o  
o  
o  
o  
Very unlikely 
Unlikely 
Quite unlikely 
Quite likely 
Likely 
Very likely 
 
4. On a typical day, knowing how many calories are in my meals would influence how much 
physical activity I do. 
 
o  
o  
o  
o  
o  
o  
Very unlikely 
Unlikely 
Quite unlikely 
Quite likely 
Likely 
Very likely 
 
5. On a typical day, knowing how much physical activity I would have to do to burn off the 
calories that are in my meals would influence how much I eat. 
 
o  
o  
o  
o  
o  
o  
Very unlikely 
Unlikely 
Quite unlikely 
Quite likely 
Likely 
Very likely 
 
6. On a typical day, knowing how much physical activity I would have to do to burn off the 
calories that are in my meals would influence how much physical activity I do. 
 
o  
o  
o  
o  
o  
o  

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Very unlikely 
Unlikely 
Quite unlikely 
Quite likely 
Likely 
Very likely 
 
7. What is your highest educational qualification? If you are a student please select the diploma 
being studied for. *consistency check* 
o No qualification 
o 1-3 GCSEs 
o 4+ GCSEs 
o A level 
o CertHE 
o DipHE 
o Higher education or Bachelor’s degree 
o Post-Graduate degree  
o Doctoral or professional degree 
 
 

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23. APPENDIX N: ADDITIONAL MEASURES 
 
IAS 
Below are several statements regarding how accurately you can perceive specific bodily sensations. 
Please rate on the scale how well you believe you can perceive each specific signal. For example, if 
you often feel you need to urinate and then realise you do not need to when you go to the toilet you 
would rate your accuracy perceiving this bodily signal as low. 
Please only rate how well you can perceive these signals without using external cues, for example, if 
you can only perceive how fast your heart is beating when you measure it by taking your pulse this 
would not count as accurate internal perception. 
 
 
 
 
 
Strongly 
disagree 
1 
 
 
Disagree 
2 
Neither 
agree nor 
disagree 
3 
 
 
Agree 
4 
 
Strongly 
agree 
5 
 
 
1. 
I can always accurately 
perceive when my heart is 
beating fast 
o 
 
o 
 
o 
 
o 
 
o 
 
2. 
I can always accurately 
perceive when I am hungry 
o 
 
o 
 
o 
 
o 
 
o 
 
3. 
I can always accurately 
perceive when I am breathing 
fast 
o 
 
o 
 
o 
 
o 
 
o 
 
4. 
I can always accurately 
perceive when I am thirsty 
o 
 
o 
 
o 
 
o 
 
o 
 
5. 
I can always accurately 
perceive when I need to 
urinate 
o 
 
o 
 
o 
 
o 
 
o 
 
6. 
I can always accurately 
perceive when I need to 
defecate 
o 
 
o 
 
o 
 
o 
 
o 
 
7. 
I can always accurately 
perceive when I encounter 
different tastes 
o 
 
o 
 
o 
 
o 
 
o 
 
8. 
I can always accurately 
perceive when I am going to 
vomit 
o 
 
o 
 
o 
 
o 
 
o 
 
9. 
I can always accurately 
perceive when I am going to 
sneeze 
o 
 
o 
 
o 
 
o 
 
o 
 
10. 
I can always accurately 
perceive when I am going to 
cough 
 
o 
 
o 
 
o 
 
o 
 
o 
 
11. 
I can always accurately 
perceive when I am hot/cold 
 
o 
 
o 
 
o 
 
o 
 
o 
 
12. 
I can always accurately 
perceive when I am sexually 
aroused 
o 
 
o 
 
o 
 
o 
 
o 
 

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13. 
I can always accurately 
perceive when I am going to 
pass wind 
o 
 
o 
 
o 
 
o 
 
o 
 
14. 
I can always accurately 
perceive when I am going to 
burp 
o 
 
o 
 
o 
 
o 
 
o 
 
15. 
I can always accurately 
perceive when my muscles are 
tired/sore 
 
o 
 
o 
 
o 
 
o 
 
o 
 
16. 
I can always accurately 
perceive when I am going to 
get a bruise 
o 
 
o 
 
o 
 
o 
 
o 
 
17. 
I can always accurately 
perceive when I am in pain 
o 
 
o 
 
o 
 
o 
 
o 
 
18. 
I can always accurately 
perceive when my blood 
sugar is low 
o 
 
o 
 
o 
 
o 
 
o 
 
19. 
I can always accurately 
perceive when someone is 
touching me affectionately 
rather than non-
affectionately 
o 
 
o 
 
o 
 
o 
 
o 
 
20. 
I can always accurately 
perceive when something is 
going to be ticklish 
o 
 
o 
 
o 
 
o 
 
o 
 
21. 
I can always accurately 
perceive when something is 
going to be itchy 
o 
 
o 
 
o 
 
o 
 
o 
 
 
 
Body Awareness subscale of SPQ short-form 
During most situations, I am aware of: 
 
 
 
 
 
 
Never 
1 
 
 
Occasionally 
2 
 
 
Sometimes 
3 
 
 
Usually 
4 
 
 
Always  
5 
 
 
1. 
Swallowing frequently 
o 
 
o 
 
o 
 
o 
 
o 
 
2. 
An urge to cough to clear my 
throat 
o 
 
o 
 
o 
 
o 
 
o 
 
3. 
My mouth being dry 
o 
 
o 
 
o 
 
o 
 
o 
 
4. 
How fast I am breathing 
o 
 
o 
 
o 
 
o 
 
o 
 
5. 
Watering or tearing of my 
eyes 
o 
 
o 
 
o 
 
o 
 
o 
 
6. 
Noises associated with my 
digestion 
o 
 
o 
 
o 
 
o 
 
o 
 

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7. 
A swelling of my body or parts 
of my body 
o 
 
o 
 
o 
 
o 
 
o 
 
8. 
An urge to defecate 
o 
 
o 
 
o 
 
o 
 
o 
 
9. 
Muscle tension in my arms 
and legs 
o 
 
o 
 
o 
 
o 
 
o 
 
10. 
A bloated feeling because of 
water retention  
o 
 
o 
 
o 
 
o 
 
o 
 
11. 
Muscle tension in my face  
o 
 
o 
 
o 
 
o 
 
o 
 
12. 
Goose bumps 
o 
 
o 
 
o 
 
o 
 
o 
 
13. 
Stomach and gut pains 
o 
 
o 
 
o 
 
o 
 
o 
 
14. 
Stomach distension or 
bloatedness 
o 
 
o 
 
o 
 
o 
 
o 
 
15. 
Palms sweating  
o 
 
o 
 
o 
 
o 
 
o 
 
16. 
Sweat on my forehead 
o 
 
o 
 
o 
 
o 
 
o 
 
17. 
Tremor in my lips 
o 
 
o 
 
o 
 
o 
 
o 
 
18. 
Sweat in my armpits 
o 
 
o 
 
o 
 
o 
 
o 
 
19. 
The temperature of my face 
(especially my ears) 
o 
 
o 
 
o 
 
o 
 
o 
 
20. 
Grinding my teeth 
o 
 
o 
 
o 
 
o 
 
o 
 
21. 
General jitteriness 
o 
 
o 
 
o 
 
o 
 
o 
 
22. 
The hair on the back of my 
neck "standing up" 
o 
 
o 
 
o 
 
o 
 
o 
 
23. 
Difficulty in focusing 
o 
 
o 
 
o 
 
o 
 
o 
 
24. 
An urge to swallow 
o 
 
o 
 
o 
 
o 
 
o 
 
25. 
How hard my heart is beating 
o 
 
o 
 
o 
 
o 
 
o 
 
26. 
Feeling constipated 
o 
 
o 
 
o 
 
o 
 
o 
 
 
 
ABQ subscales 
Please read each statement and tick the box most appropriate to you 
 
 
 
 
 
Strongly 
disagree 
1 
 
 
Disagree 
2 
Neither 
agree nor 
disagree 
3 
 
 
Agree 
4 
 
 
Strongly agree 
5 

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1. 
I often feel so hungry that I 
have to eat something right 
away 
o 
 
o 
 
o 
 
o 
 
o 
 
2. 
I often notice my stomach 
rumbling 
 
o 
 
o 
 
o 
 
o 
 
o 
 
3. 
If I miss a meal I get irritable 
 
o 
 
o 
 
o 
 
o 
 
o 
 
4. 
If my meals are delayed I get 
light-headed 
 
o 
 
o 
 
o 
 
o 
 
o 
 
5. 
I often feel hungry 
 
o 
 
o 
 
o 
 
o 
 
o 
 
6. 
I eat more when I'm annoyed 
o 
 
o 
 
o 
 
o 
 
o 
 
7. 
I eat more when I'm worried  
 
o 
 
o 
 
o 
 
o 
 
o 
 
8. 
I eat more when I'm upset 
 
o 
 
o 
 
o 
 
o 
 
o 
 
.9 
I eat more when I'm anxious  
 
o 
 
o 
 
o 
 
o 
 
o 
 
10. 
I eat more when I'm angry 
 
o 
 
o 
 
o 
 
o 
 
o 
 
11. 
I often leave food on my plate 
at the end of a meal  
 
o 
 
o 
 
o 
 
o 
 
o 
 
12. 
I often get full before my meal 
is finished  
 
o 
 
o 
 
o 
 
o 
 
o 
 
13. 
 
I get full up easily  
 
o 
 
o 
 
o 
 
o 
 
o 
 
14. 
I cannot eat a meal if I have 
had a snack just before 
 
o 
 
o 
 
o 
 
o 
 
o 
 
 
 
 
Intuitive Eating Scale 
For each item, please select the answer that best characterizes your attitudes or behaviours.  
 
 
 
 
 
Strongly 
disagree 
1 
 
 
Disagree 
2 
Neither 
agree nor 
disagree 
3 
 
 
Agree 
4 
 
 
Strongly agree 
5 
 
 
1. 
I try to avoid certain foods 
high in fat, carbohydrates, or 
calories. 
o 
 
o 
 
o 
 
o 
 
o 
 
2. 
I have forbidden foods that I 
don’t allow myself to eat. 
o 
 
o 
 
o 
 
o 
 
o 
 

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3. 
I get mad at myself for eating 
something unhealthy  
o 
 
o 
 
o 
 
o 
 
o 
 
4. 
If I am craving a certain food, 
I allow myself to have it. 
o 
 
o 
 
o 
 
o 
 
o 
 
5. 
I allow myself to eat what 
food I desire at the moment.  
o 
 
o 
 
o 
 
o 
 
o 
 
6. 
I do NOT follow eating rules 
or dieting plans that dictate 
what, when, and/or how 
much to eat. 
o 
 
o 
 
o 
 
o 
 
o 
 
7. 
I find myself eating when I’m 
feeling emotional (e.g., 
anxious, depressed, sad), even 
when I’m not physically 
hungry. 
o 
 
o 
 
o 
 
o 
 
o 
 
8. 
I find myself eating when I am 
lonely, even when I’m not 
physically hungry. 
 
o 
 
o 
 
o 
 
o 
 
o 
 
9. 
I use food to help me soothe 
my negative emotions.  
o 
 
o 
 
o 
 
o 
 
o 
 
10. 
I find myself eating when I am 
stressed out, even when I’m 
not physically hungry.  
o 
 
o 
 
o 
 
o 
 
o 
 
11. 
I am able to cope with my 
negative emotions (e.g., 
anxiety, sadness) without 
turning to food for comfort.  
o 
 
o 
 
o 
 
o 
 
o 
 
12. 
When I am bored, I do NOT 
eat just for something to do. 
o 
 
o 
 
o 
 
o 
 
o 
 
13. 
 
When I am lonely, I do NOT 
turn to food for comfort. 
o 
 
o 
 
o 
 
o 
 
o 
 
14. 
I find other ways to cope with 
stress and anxiety than by 
eating.   
o 
 
o 
 
o 
 
o 
 
o 
 
15. 
I trust my body to tell me 
when to eat. 
 
o 
 
o 
 
o 
 
o 
 
o 
 
16. 
I trust my body to tell me 
what to eat. 
o 
 
o 
 
o 
 
o 
 
o 
 
17. 
I trust my body to tell me how 
much to eat. 
o 
 
o 
 
o 
 
o 
 
o 
 
18. 
I rely on my hunger signals to 
tell me when to eat. 
o 
 
o 
 
o 
 
o 
 
o 
 
19. 
I rely on my fullness (satiety) 
signals to tell me when to 
stop eating. 
o 
 
o 
 
o 
 
o 
 
o 
 
20. 
I trust my body to tell me 
when to stop eating. 
o 
 
o 
 
o 
 
o 
 
o 
 
21. 
Most of the time, I desire to 
eat nutritious foods. 
o 
 
o 
 
o 
 
o 
 
o 
 
22. 
I mostly eat foods that make 
my body perform efficiently 
(well). 
o 
 
o 
 
o 
 
o 
 
o 
 
23. 
I mostly eat foods that give 
my body energy and stamina. 
o 
 
o 
 
o 
 
o 
 
o 
 

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DASS21 
Please read each statement and rate how much the statement applied to you over the last year. 
There are no right or wrong answers. Do not spend too much time on any statement. 
 
 
 
 
0 
Did not 
apply to 
me at all 
 
1 
Applied to me to some 
degree, or some of the 
time 
2 
Applied to me to a 
considerable 
degree or a good 
part of time 
3 
Applied to me very 
much or most of the 
time 
 
1. 
I found it hard to wind down 
o 
 
o 
 
o 
 
o 
 
2. 
I was aware of dryness of my 
mouth 
o 
 
o 
 
o 
 
o 
 
3. 
I couldn’t seem to experience any 
positive feeling at all 
o 
 
o 
 
o 
 
o 
 
4. 
I experienced breathing difficulty 
(e.g. excessively rapid breathing, 
breathlessness in the absence of 
physical exertion) 
o 
 
o 
 
o 
 
o 
 
5. 
I found it difficult to work up the 
initiative to do things 
o 
 
o 
 
o 
 
o 
 
6. 
I tended to over-react to situations 
o 
 
o 
 
o 
 
o 
 
7. 
I experienced trembling (e.g. in the 
hands) 
o 
 
o 
 
o 
 
o 
 
8. 
I felt that I was using a lot of 
nervous energy  
o 
 
o 
 
o 
 
o 
 
9. 
I was worried about situations in 
which I might panic and make a 
fool of myself 
o 
 
o 
 
o 
 
o 
 
10. 
I felt that I had nothing to look 
forward to 
o 
 
o 
 
o 
 
o 
 
11. 
I found myself getting agitated 
o 
 
o 
 
o 
 
o 
 
12. 
I found it difficult to relax 
o 
 
o 
 
o 
 
o 
 
13. 
 
I felt down-hearted and blue 
o 
 
o 
 
o 
 
o 
 
14. 
I was intolerant of anything that 
kept me from getting on with what 
I was doing 
o 
 
o 
 
o 
 
o 
 
15. 
I felt I was close to panic  
o 
 
o 
 
o 
 
o 
 
16. 
I was unable to become 
enthusiastic about anything 
o 
 
o 
 
o 
 
o 
 
17. 
I felt I wasn’t worth much as a 
person  
o 
 
o 
 
o 
 
o 
 
18. 
I felt that I was rather touchy 
o 
 
o 
 
o 
 
o 
 
19. 
I was aware of the action of my 
heart in the absence of physical 
exertion (e.g. sense of heart rate 
increase, heart missing a beat) 
o 
 
o 
 
o 
 
o 
 

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52 
 
20. 
I felt scared without any good 
reason 
o 
 
o 
 
o 
 
o 
 
21. 
I felt that life was meaningless. 
o 
 
o 
 
o 
 
o 
 
 
Weight stigma 
 
 
 
 
Strongly 
disagree 
1 
 
 
Disagree 
2 
 
Disagree 
somewhat 
3 
Neither 
agree nor 
disagree 
4 
 
Agree 
somewhat 
5 
 
 
Agree 
6 
 
Strongly 
agree 
7 
1. 
I am less attractive 
than most other people 
because of my weight. 
o 
 
o 
 
o 
 
o 
 
o 
 
o 
o 
 
2. 
I wish I could 
drastically change my 
weight. 
o 
 
o 
 
o 
 
o 
 
o 
 
o 
o 
 
3. 
Whenever I think a lot 
about being 
overweight, I feel 
depressed. 
o 
 
o 
 
o 
 
o 
 
o 
 
o 
o 
 
4. 
I hate myself for being 
overweight. 
o 
 
o 
 
o 
 
o 
 
o 
 
o 
o 
 
5. 
I don’t feel that I 
deserve to have a really 
fulfilling social life, as 
long as I’m overweight. 
o 
 
o 
 
o 
 
o 
 
o 
 
o 
o 
 
 
6. How would you describe your weight? 
 Very underweight 
 Underweight 
 About right 
 Overweight 
 Very overweight 
 
7. How often have you been mistreated, discriminated against or treated unfairly because of your 
weight?  
 Never 
 Once in your life 
 Several times in your life 
 About once a year 
 Several times per year 
 About once a month 
 Several times per month 
 About once a week 
 Several times per week 
 Daily 
 
8. I am concerned that other people's opinion of me will be based on my weight. 

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53 
 
Strongly 
disagree 
Disagree 
Disagree 
somewhat 
Neither agree nor 
disagree 
Agree 
somewhat 
Agree 
Strongly 
agree 
o 
 
o 
 
o 
 
o 
 
o 
 
o 
o 
 
 
Diagnosis of a psychiatric condition  
Have you ever been diagnosed with a psychiatric condition (e.g. Depression, Schizophrenia)? 
o Yes  
o No 
 
Diagnosis of chronic health condition  
Do you have any chronic medical conditions that affect your health (e.g. Diabetes, Heart Disease)? 
o Yes  
o No 
 
 

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24. APPENDIX O: DEBRIEFING TEXT 
“Thank you very much for your participation. In this study we were interested in the effect of energy 
labelling on the size of self-served food portions. 
All the participants saw the same 18 dishes, but in different randomised order and in four different 
conditions. In the first condition, the dishes were all presented without any labelling. In the second 
condition, the dishes were presented alongside with energy labelling in kcal showing the number of 
calories for each portion size. In the third condition, the dishes were presented with an exercise 
equivalent energy labelling showing the number of minutes needed to walk to burn off the calories 
for each portion size. In the fourth condition, the dishes were presented with a combination of energy 
in kcal and exercise equivalent energy labelling showing the number of calories and the number of 
minutes needed to walk to burn off the calories for each portion size. 
We will compare self-served energy by participants in the four conditions. The results will help to 
identify the effective interventions to reduce energy intake. 
You also answered questionnaires about your food choices motivations and physical activity. We will 
test if the ones who are the most motivated by health in their food choices and who are more 
physical active were more likely to use energy information when deciding how much to eat. 
You also filled in questionnaires about bodily sensations and intuitive eating that will help us to 
design a future study investigating the link between attention to bodily state and eating behaviour.”