Measuring Disability Prevalence Daniel Mont, HDNSP Disability and Development Team June 6, 2007

World Bank and Disability – What is the link? The World Bank’s mission is to eliminate poverty The World Bank’s mission is to eliminate poverty Disability leads to poverty, and poverty leads to disability Disability leads to poverty, and poverty leads to disability Disability affects not just disabled people, but their families and communities Disability affects not just disabled people, but their families and communities Doing a good job on poverty alleviation requires taking disabled people into account Doing a good job on poverty alleviation requires taking disabled people into account

Problems with existing data  Often not available  Definitions and measures not standard and often outdated  Quality is poor

Prevalence Rates Vary Dramatically (Censuses) United States19.4% United Kingdom12.2% Uganda3.5% Mexico2.3% India2.1% Kenya0.7%

Prevalence Rates Vary Dramatically – (Surveys) New Zealand20.0% Spain15.0% Ecuador12.1% Nicaragua10.3% China5.0% Egypt4.4%

Medical Model vs. Social Model  Medical model – Disability is a physical, mental or psychological health condition that limits a person’s activities  Social model – Disability arises from the interaction of a person’s functional status with the environment

Medical versus Social Model  PERSONAL vs. SOCIAL  Medical care vs. Social integration  Individual treatment vs. Social action  Professional help vs. Individual and collective responsibility  Personal adjustmentvs. Environmental adjustment  Behavior vs. Attitude  Care vs. Human rights  Individual adaptationvs. Social change

WHO’s International Classification of Functioning, Disability and Health (ICF)  Incorporates social model approach  Describes facets of human functioning that may be affected by a health condition  Purpose: provide a scientific basis for the consequences of health conditions establish a common language to improve communications permit comparisons of data across countries and health care disciplines, provide a systematic coding scheme for health information systems

ICF Domains – Body Function and Structure  Physiological and psychological function of body systems  Very specific recording of detailed functional abilities and impairments  Not linked to cause. For example, fluency and rhythm of speech functions – could be from stuttering, stroke, or autism

Activities and Participation  Describes individual’s functioning as a whole person  Range from Basic to Complex Basic: e.g., walking, eating, and bathing Complex: e.g., work and schooling  Activities – tasks an individual can do that require multiple body functions  Participation – higher order activities that involve integration in the community

ICF is a Functionally Based System  ICF does not measure disability It describes people’s functional abilities in various domains  Health conditions that affect functional status are not part of classification system  Disability is not an “all or nothing” concept  Disability arises out of the environmental context

Health Condition ( disorder/disease ) International Classification of Functioning, Disability and Health (ICF) Environmental Factors Personal Factors Body function&structure (Impairment ) Activities(Limitation)Participation(Restriction)

How can we capture such a complex concept of disability in a single measure?

Why not ask this old question?  Do you have a physical, mental, or emotional health condition that limits the amount or type of work you can do?

Because…  In some sense, the answer for everyone is “YES”  The answer is a function of the environment the respondents live in Physical environment Cultural environment Policy environment  The answer is a function of their particular circumstances at the time  The question is very complex and easily misinterpreted

Why not ask this question?  Do you have a disability?

Under counts what most people consider disability  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, especially for mental and psychological  People think of disability relative to their expectations of normal functioning so it undercounts the elderly

Why not ask detailed diagnosis questions?  Many people don’t have or don’t know their diagnosis  Some diagnoses have intense stigma  A diagnosis doesn’t tell you much about ability to function  Can miss age related disabilities  If people have multiple diagnoses they’ll often report only one The one with less stigma The one that occurred first The one that’s most visible  Ability and willingness to report often depends on their interaction with health services and thus other socio- demographic factors

Census-based Disability Rates Do you have a disability? Nigeria0.5 Jordan1.2 List of conditions Mexico1.8 Uganda3.5 Activity Based Poland10.0 Brazil14.5

Where we focus on this model depends on the purpose of measurement Health Condition ( disorder/disease ) Environmental Factors Personal Factors Body function&structure (Impairment ) Activities(Limitation)Participation(Restriction)

National prevalence rates  Internationally comparable  Capture broad spectrum of those with disabilities  Questions suitable for census  To examine the relationship between disability and socio-economic outcomes

Equalization of Opportunity  UN Washington Group concluded that Equalization of Opportunities was most appropriate for a census.  So ask participation questions? No. That identifies the segment of the population that is not participating so can’t look at progress of inclusion Not internationally comparable

 Activity level questions indicate whether a person is having difficulty with important tasks  If these activity limitations are correlated with outcome measures (e.g., poverty) this indicates there are important barriers to participation

WG Questions  Because of a physical, mental or emotional health condition… Do you have difficulty seeing, even if wearing glasses? Do you have difficulty hearing, even if wearing hearing aid/s? Do you have difficulty walking or climbing stairs? Do you have difficulty remembering or concentrating Do you have difficulty with self-care, such as washing all over or dressing? Do you have difficulty communicating (for example, understanding or being understood by others)? Response categories: No, Some, A lot, Unable

Cognitive Testing  To examine interpretation of questions  Conducted in about 15 countries  Performed very well  Issues: Difficulty with glasses and hearing aid/s clause Communication question

Field Testing  Vietnam and South Africa  UNESCAP testing in Philippines, Fiji, India, Indonesia and Mongolia  Again, responses fairly robust

Responses  Scaled responses No, Some, A lot, and Unable Allows user to shift threshold as desired Captures heterogeneity of disability

Activity Limitation Scores - Zambia

Recommendations for General Prevalence Measures  Questions should be based on functionality  Questions should focus on core activities Equalization of opportunity International comparability  Do not use the word “disability”  Responses should be scaled  A range of prevalence should be reported for various levels of severity, rather than a single prevalence rate

Do you have difficulty walking or climbing steps? Pct Cumulative Pct Some difficulty16.6 A lot of difficulty Unable Mobility Limitations in Vietnam

UNESCAP Field Testing IndiaIndonesiaMongolia Seeing Mild Severe/Unable Cognitive Mild Severe/Unable

Disability Rates in LAC TotalMaleFemale Brazil Ecuador Nicaragua

Disability Prevalence  Ecuador 12.1%  Nicaragua 10.3%  Brazil 14.5%  Zambia 13.1%  Vietnam 10.5% (preliminary)  India 8%  Roughly, 10-12% is reasonable estimate with less than half “severe” and about 1- 2% incapable of self-care