The Definition and Measurement of Disability: The Work of the Washington Group (continued)

1. The Definition and Measurement of Disability: The Work of the Washington Group (continued) Daniel Mont Disability and Development Group The World Bank November 9, 2006

2. Cognitive Testing • Cognitive testing was undertaken in 15 countries to ensure validity and better understand how the questions operate. • Purposive Samples • Asked WG question and series of detailed questions in the same domains • Collected information on response process • Analyzed problematic response patterns • Questions performed well with a few issues: • Glasses and hearing aid clauses • Communication question

3. More detailed questions on functioning. For example, Cognitive Questions • Do you have difficulty remembering the names of people or places? • Do you have difficulty remembering appointments? • Do you have difficulty remembering how to get to familiar places? • Do you have difficulty remembering important tasks, like taking medications or paying bills? • Do you have difficulty concentrating on doing something for ten minutes? • Do you have difficulty learning a new task, for example, learning how to get to a new place? • Do you have difficulty finding solutions to problems in day to day life?

4. Information on response process • Questions to interviewers • Need to repeat any part of the question? • Any difficulty in using response options? • Did respondents ask for clarification or qualify their answers? • Follow-up probes to understand response process

5. Correlates of cognition difficulty

6. Correlates of cognition difficulty

7. Socio- demographic correlates of cognition difficulty

8. Overall, questions worked well • Well understood • Responses consistent • Two problem areas • Glasses clause – WG is revisiting but solution has a lot to do with translation protocol • Communication Question – WG will revisit to see if question can be simplified

9. Field Testing • Undertaken in South Africa and Vietnam • Checking for Internal consistency • Results comparable to changes seen in other countries with move towards functional approach to measuring disability

10. WG Census Question vs. Extended Questions For Field Test • Constructed three thresholds for disability based on WG census question: D1=1 if any difficulty, D2=1 if a lot, D3=1 if unable to do • Constructed three thresholds for disability based on extended questions: ED1, ED2, ED3 • What was the D measure picking up compared to the ED measures?

11. Example: Mobility question • WG question: • Do you have difficulty walking or climbing steps? • D1=1 if “some difficulty”, “a lot of difficulty”, or “cannot do at all” • D2=1 if “a lot of difficulty” or “cannot do at all” • D3=1 if “cannot do at all” • Extended Questions: • Do you have difficulty going outside of your home?(0) • Do you have difficulty walking a long distance such as a kilometer (or a mile)? • ED1=1 if “some”, “a lot” or “cannot do” for either question • ED2=1 if “a lot” or “cannot do at all” for either question • ED3=1 if “cannot do at all” for either question

13. Vietnam Disability Rates – Thai Binh Province

15. Functional Questions Lead to Higher Rates of Disability • Many Developing Country Censuses ask “Do you have a disability?” but… • People think of disability as very serious and won’t report minor or moderate disabilities • “Disability” creates shame and stigma so people do not want to identify themselves that way, • People think of disability relative to their expectations of normal functioning so it undercounts the elderly • Switch to Functional Questions raises disability rate • E.g., Brazil 14.5%, Ecuador 12.1%, Zambia 13.1%, Nicaragua 10.3%

16. But, no such thing as a single prevalence rate • In Ecuador, 12.1% of the population has a disability but 4% are significantly disabled. Which is the right number? • In a field-test of WG questions in India, 4% of the population has great difficulty walking or cannot walk, but 18% of the population has some difficulty walking? Which is the right number? • It depends why you are asking

17. SINTEF study in Zambia (Loeb and Eide) • Nationally representative sample • WG questions as screen • All disabled respondents asked detailed follow-up activity limitation questions • Sample of non-disabled respondents asked similar questions

18. 9 Domains & 44 Activities • Basic learning & applying knowledge: reading, writing • Communication: producing and receiving messages • Mobility: walking, moving around • Self-care: washing, dressing • Domestic life: shopping, preparing meals • Sensory experiences: watching, listening • Interpersonal relations: making friends, interacting with strangers • Major life areas: going to school, getting a job • Community, social and civic life: clubs, religious, politics

19. Activity Limitation (a measure of capacity) How DIFFICULT it is for you to perform this activity WITHOUT ASSISTANCE? • 0 - no difficulty • 1 - slight difficulty • 2 - moderate difficulty • 3 - severe difficulty • 4 - unable to carry out the activity

20. Activity Limitations Activity limitation score

21. Disability Data Collection Recommendations • Do not use the word disability • Functional approach • Separate functional domains • Scaled Responses • Definition of disability can be made ex post, and hinge on domains and thresholds used