Sample design

Sample members are drawn from respondents to the Health Survey for England (HSE). ELSA participants have a face-to face interview (a computer-assisted personal interview followed by a self-completion questionnaire). A nurse assessment is also carried out. For waves 1-7, this was carried out on the whole sample every four years. From wave 8 onwards, a nurse assessment was carried out on half the sample every two years.

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At waves 3, 4, 6, 7 and 9, the study was replenished with new study participants (refreshments) from HSE to maintain the size and representativeness of the panel.

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At wave 3, respondents were invited to participate in a life-history interview to capture information about important events that had taken place previously in their lives.

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Wave 9 data collection, which now includes an online dietary questionnaire, began in July 2018.

 

Data collection

ELSA fieldwork is coordinated by our partner NatCen Social Research. To enable longitudinal analysis, the same key topics are included in the content of the questionnaire for each wave, while others may be rotated on and off.

 

The nurse interview involves measurements of physical function, anthropometric measurements and collection of blood samples (for extraction of biomarkers and DNA).

 

To view which basic topics are asked at individual waves and the biomarkers that are analysed, please click here.