1. Defining disability in MAP2030

2. Rationale Disability is used as an input to or output from every WP A variety of data sources (surveys) are used by each WP Not complete overlap between disability items in each of the surveys Aim: to agree definition of disability that is comparable between surveys and therefore WPs

3. Disease>Impairment>Functional limitation>Disability (Nagi, 1965,1976, 1991) Disease>Impairment>Functional >Activity Restriction>Handicap limitation (Wood, 1975) Disease>Impairment>Disability>Handicap (ICIDH, 1980) Models of the disablement process What is disability?

4. Components Functional limitations Reaching, stretching, lifting, dexterity Household Activities (IADL) Shopping, cooking, housework, managing affairs Personal Care Activities (ADL) Bathing, dressing, feeding, getting in and out of bed, using toilet Mobility Getting up and down stairs/steps, walking across a room, walking half a mile, getting around outside

5. Surveys General Household Survey (GHS) A multi-purpose continuous survey of people living in private households (approx 13,000 household sampled) in Great Britain. Started in 1971 and has been carried out continuously since then, except for breaks in 1997/98 and 1999/2000. All adults aged 16 and over are interviewed in each responding household. Demographic and health information is also collected about children in the household. English Longitudinal Study of Ageing (ELSA) A panel study of 11,500 people aged 50 and older, drawn from the Health Survey for England and interviewed every two years (since 2002) with a nurse visit every four years. British Household Panel Study (BHPS) Annual survey consisting of nationally representative sample of about 5,500 households recruited in 1991. Individuals re-interviewed each year, still followed if they split off from original households, new members to household included as are all adult members of the household so the sample remains representative. Additional samples recruited later mean the study now covers the whole UK. Now contains total of approximately 10,000 interviewed individuals. MRC Cognitive Function and Ageing Study (CFAS) Longitudinal study of 13,004 aged 65+ in 5 centres 1991-2001 includes institutionalised

6. Comparison of items in surveys

7. Standardised prevalence of disability (difficulty) age 65+

8. Standardised prevalence of disability (difficulty) age 75+

9. Standardised prevalence of disability (help) age 75+

10. Hierarchy of items (CFAS) - longitudinal

11. Hierarchy of items (CFAS) by gender

12. Why differences might occur Filters ‘If cannot manage steps/stairs can ….’ (GHS)

13. Effect of filtering by difficulty with stairs women aged 75+

14. Why differences might occur Filters ‘If cannot manage steps/stairs can ….’ (GHS) Question wording ‘Because of a health or memory problem’ (ELSA) Responses Very easy, fairly easy, fairly difficult, very difficult (GHS, BHPS) No difficulty, some difficulty (CFAS) Position of question in survey

15. Next steps Obtain standardised prevalence (help) for BHPS items Review cross-sectional hierarchy for each survey –is ordering the same regardless of items? Explore longitudinal hierarchy for BHPS? Try to find equivalent arrangement across surveys for difficulty with 1 or more items