National Diet and Nutrition Survey: Linking data

More information about data we would like to link to your survey and why it is important.

What is linking data?

At some point during your participation we will ask for your permission to link your questionnaire answers to other administrative data, in this case your health records. 

To take part in the study you do not have to give your permission to link your data at all. This is your choice and will not affect your participation otherwise.

Why is linking data important?

Linking your answers to other data will help us build a more complete picture of your life. This information allows us to look at how a person’s lifestyle can have an impact on their future health. For example, if a person who took part in the NDNS gets cancer or dies, the type of cancer or cause of death will be linked to the survey.

When you take part in NDNS we will ask if you agree for us to link your survey results to the health records listed below. There are different governing bodies so which you will be asked about depends on which country you live in. You can choose to agree to all, some or none of them.

  • England: Hospital Episodes Statistics data, civil registration mortality data and Cancer Registration data (held by NHS England).
  • Wales: Patient Episode Database for Wales & Outpatient Activity Minimum Dataset (held by NHS Wales Informatics Service), Deaths Register (held by Office for National Statistics); Welsh Cancer Intelligence and Surveillance Data (held by Public Health Wales).
  • Scotland: Administrative health data, civil registration mortality data & Cancer Registration data (all held by Information Services Division (ISD) of NHS Scotland and National Records Scotland (NRS)).
  • Northern Ireland: Patient Administration System (held by Northern Ireland Health and Social Care Trust); civil registration mortality data (held by Northern Ireland Statistics and Research Agency (NISRA)); Northern Ireland Cancer Registry (held by Queens University Belfast and Public Health Agency).

This is how the process works for NDNS:

  • We’ll separate your name, address and date of birth from your other answers and pass them over to the government department or organisation who hold your health records.
  • They’ll use your details to find your records, then they will delete the personal information that we passed to them.
  • Your records are then linked back up with your survey answers to create a new set of anonymous data to be used by researchers. This will include all the useful information from your records - but no one will know it’s about you.
  • The information will only be used for statistical and research purposes.
  • When you consent to data linkage you are only giving us permission to link survey information to the above health records. We will in no way be able to obtain any other details from your medical records.

You can withdraw your permission to data linkage at any time.

If you do wish to withdraw your consent, please write to 

National Centre for Social Research,
Unit 15 Ashton Gate, Ashton Road,
Romford, Essex, RM3 8UF

Survey Enquiry Team: 0800 652 4572
Email: ndns@natcen.ac.uk