<p>The nurse interview comprised a personal face-to-face CAPI interview, the taking of a number of different measures and an additional voluntary self-completion questionnaire. The nurse visit has been a feature of HSE since the survey was first carried out in 1991. When the nurse visit was incorporated into ELSA, most modules from the HSE nurse visit were kept and a number of new ones were added in. The modules that were taken from HSE were blood pressure, blood sample, standing and sitting height, weight, waist and hip measurement and lung function. The modules that were added were balance, leg raise, chair rise, grip strength, and the saliva log. The first three of these new measurements, taken alongside the walking speed measurement carried out in the main ELSA interview, form a battery of tests that have been shown to be highly predictive of level of disability, future use of health care and mortality. These measures were adapted from the EPESE (Established Populations for Epidemiologic Studies of the Elderly) protocol, which looks at older cohorts and the development of disability. 1,2 The grip strength measure was taken from the Survey of Health, Ageing and Retirement in Europe (SHARE).</p>