Determining perceptive thresholds in static facial asymmetry


1. Title of Study

Determining perceptive thresholds in static facial asymmetry

2. Version Number and Date

1 (17/03/2021)

3. Invitation Paragraph

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 do not have to accept this invitation and should only agree to take part if you want to.

We are investigating the amount of facial asymmetry is required to become noticeable. In this survey you will be shown 3 example images of symmetrical faces and then shown a further 36 faces, half of the images will be inverted. You will be asked if the faces are symmetrical or asymmetrical. If you believe the face is asymmetrical, you will be asked to identify the abnormal side and what the deformity is.

4. What is the purpose of the study?

Knowing what amount of asymmetry is noticeable to people is important in important in counselling patients preoperatively when having eyelid malposition surgery, and also informs the surgeon to what degree of symmetry they should aim for.

We are also investigating whether the orientation of the face affects people’s ability to notice asymmetry. During facial surgery the surgeon stands behind the head and views the person’s face upside down. It is our contention that this judgement is impaired when the face is upside down. Proving this may influence surgeon behaviour and improve outcomes.

5. Why have I been chosen to take part?

You have been chosen as you are a consultant, speciality doctor, trainee, or allied healthcare professional.

6. Do I have to take part?

You are not required to take part. Emphasis should be put on the fact that even if you have signed the consent form, completed the survey, you are still able to withdraw from the study, without providing an explanation or reason why.

7. What will happen if I take part?

You will be sent a link to complete an online survey on the site “Jisc, online surveys”. The survey will involve viewing a total of 36 images of people’s faces, with half of the images will be inverted.

You will be asked for each image if you believe it is symmetrical or asymmetrical. If you believe the face is asymmetrical, you will be asked to identify the abnormal side, and also what you believe the deformity to be.

8. How will my data be used?

No participant identifiable data other than age, gender, level of training and sub-speciality will be collected, in addition to the survey responses. The data will be stored on the university M drive only, within an excel spreadsheet, and after 2 years the principal investigator will ensure that the files are deleted.

9. Will my taking part in the research be kept confidential?

Yes. We will follow current ethical and legal practice and all information collected will be handled in confidence.

10. Expenses and/or payments

There are no expenses and/or payments for taking part in this study.

11. Are there any risks in taking part?


12. Are there any benefits in taking part?

The study offers no direct personal benefit; however, you will be aiding in work which may go on to inform further research into facial asymmetry perception.

13. What will happen to the results of the study?

The results of the study will go towards a submission to the University of Liverpool for a Clinical Sciences Masters of Research project, and subsequently be accessible through any abstracts, conference presentations or publications that are successfully completed.

14. What will happen if I want to stop taking part?

You are free to withdraw from the study at any time, without an explanation, if you wish to.

15. What if I am unhappy or if there is a problem?

If you become unhappy or there is a problem, you are encouraged to let the research team know by contacting the principal investigator (contact details below), who will try and help you with either issue. If you continue to feel unhappy or have a complaint you feel you cannot raise with us, then you are able to contact the Research Governance Officer at the email address ‘’ – within the email provide details of the name of the study, the researcher(s) involved and the complaint you want to make.

16. Who can I contact if I have further questions?

You can contact either the student investigator (Frank Preston) or the principal investigator (Austin McCormick) whose details can be found below.

Contact details of investigatory team

Principal Investigator
Mr Austin McCormick

Student Investigator Frank Preston