Slide 1:
The Definition of Disability and Statistics
Presented by:

Andrew J. Houtenville, Ph.D.
Employment and Disability Institute

Rehabilitation Research and Training Center on
Disability Demographics and Statistics

Slide 2:
Objective of Today’s Presentation

Give a flavor of the powerful statistics that can be generated from national surveys 
that have disability-related information.

Highlight the complex of defining disability in the context of disability statistics

Discuss the role the definition of disability plays in drawing inferences from 
disability statistics.

Give a Quiz.

Slide 3:
Question 1

It is not surprising that there is no single definition of disability among large 
national surveys and polls.  These surveys have different purposes and histories.  
The population with disabilities is diverse in many ways: types of disabilities, the 
socio-environment component of disability, and the areas of personal and social 
activities affected by disability.  Given all of this complexity and the normative 
nature of disability, why is it still important to know the number of people with 
disabilities?  [Hint: What I am thinking of has something to do with money.]

Slide 4: 
CHART
Title: Reporting of a Work Limiting Health Problem or Disability among Persons Ages 25-61
Source: Author’s calculations using the Current Population Survey (CPS), 1981-2003.

Slide 5:
CHART
Title: Reporting of a Work Limiting Health Problem or Disability among Persons Ages 25-61,
by State, in 2003
Source: Author’s calculations using the Current Population Survey (CPS), 2003.

Slide 6:
CHART
Title: Poverty Rate, by Work Limitation Status (Ages 25-61)
Source: Author’s calculations using the Current Population Survey (CPS), 1981-2003.

Slide 7: 
CHART
Title: Receipt of Supplemental Security Income (SSI), by Work Limitation Status (Ages 25-61)
Source: Author’s calculations using the Current Population Survey (CPS), 1981-2003.

Slide 8: 
Question 2

OPPS:  How many people with disabilities are there in the United States and what is 
the definition of disability?

Slide 9: 
Possible Answer

* 54 million is often cited.
	- Corresponds to a prevalence rate of 20.6 percent.
	- Based on Census Bureau estimates using the 1994 SIPP.
	- Non-institutionalized, Civilians, the 2000 Census reports about 2 million people living 
	in disability-related institutions.
	- A “kitchen sink” definition of disability (e.g., one or more ADLs/IADLs; use of a 
	wheelchair, a cane, crutches, or a walker; receipt of federal disability benefits)

	- Source: http://www.census.gov/prod/3/97pubs/p70-61.pdf

Slide 10:
Other Answers

* National Health Interview Survey (NHIS)
	- 34 million (or 12 percent of) non-institutionalized civilians of all ages are limited in 
	usual activities due to one or more chronic health conditions in 2002. 
	- Source: www.cdc.gov/nchs/data/series/sr_10/ sr10_220.pdf

* American Community Survey (ACS)
	- 41 million (or 13 percent of) non-institutionalized civilians ages 5 and older have a 
	disability in 2002 
	- Source: www.census.gov/acs/www

* March Current Population Survey (CPS)
	- 22 million (or 10 percent of) non-institutionalized civilians ages 16 to 64 reported a 
	work disability in 2002.
	- Source: www.census.gov/hhes/www/disability.html

Slide 11:
Question 3

* What is the best definition of disability available in Federal surveys?  Explain your answer.
	- Possible Answer: There is no gold standard.  It depends on the reason why you need to define 
	disability.  You must choose wisely, and whenever possible, get information in as great a 
	deal and from as many sources as possible. 

Slide 12:
Example: Disability-Related Questions in the ACS and 2000 Census Long-Form

* Does this person have any of the following long-lasting conditions: 
(a) Blindness, deafness, or a severe vision or hearing impairment? 
(b) A condition that substantially limits one or more basic physical activities such as walking, 
climbing stairs, reaching, lifting, or carrying?

* Because of a physical, mental, or emotional condition lasting 6 months or more, does this 
person have any difficulty in doing any of the following activities: 
(a) Learning, remembering, or concentrating? 
(b) Dressing, bathing, or getting around inside the home? 

Slide 13: 
CHART
Title: Prevalence of Disability among Persons Ages 25-61, by Type, 2002 American Community Survey
Source: Calculations by Robert Weathers, Cornell University, using the 2002 American Community 
Survey.

Slide 14: 
CHART
Title: Conceptual Definition of Disability—Nagi

Slide 15:
CHART
Title: Prevalence of Disability among Persons Ages 25-61, by Type, 2002 American Community Survey
Source: Calculations by Robert Weathers, Cornell University, using the 2002 American Community 
Survey.

Slide 16: 
Question 4

* How many people who reported being “blind in both eyes” DID NOT report a health condition or 
impairment that limited the kind or amount of work they could do.
	- Possible Answer: About 31 percent.

Slide 17: 
Table
Title: Prevalence of Reporting Specific Impairments Among Working Age Persons 
(NHIS, pooled 1983-96)

Group: Blind in Both Eyes 
Prevalence Rate: 0.15%
Share Reporting Work Limitation: 69.0%

Group: Deaf in both Ears
Prevalence Rate: 0.37%
Share Reporting Work Limitation: 38.0%

Group: Cerebral Palsy
Prevalence Rate: 0.09%
Share Reporting Work Limitation: 74.5%

Slide 18:
CHART
Title: Employment Rate Among Working Age Men who Report Disability, Using Alternative Disability 
Definitions from the NHIS and CPS, 1981-2000

Slide 19:
Question 5

* While I am here ... The unemployment rate is around 5 to 6 percent.  What is the unemployment rate 
among people with disabilities?
	- Possible Answer: About 20 percent, depending on the definition of disability.

Slide 20: 
Question 6

* The unemployment rate is the percentage of the labor force who are employed.  The labor force is 
defined as those are employed or have actively looked for work in the last four weeks.  Why wouldn’t 
the unemployment rate be a good measure to identify the lack of employment among working age people 
with disabilities? [Hint: Who would be left out of the labor force?]
	- Possible Answer: It drops people who have not "actively looked for work in the past four 
	weeks", thus it would miss people with disabilities that are discouraged in the job search 
	process, and it would also miss people on DI and SSI—a population we know increase 
	dramatically in the 1990s.

Slide 21:
CHART
Title: Conceptual Definition of Disability—ICF/WHO

Slide 22:
Question 7

* The Nagi frameworks acknowledge the role of the environment in the transformation of 
“pathologies/impairments” into “functional limitations/ disabilities”.  The ICF is attempting to 
codify and quantify the environmental components of “disability”.  Suppose you suggested to a health 
insurance company that it use the ICF rather than their current health based classification system 
(ICD-10).  What do you think would be the response of the health insurance company?  What would a 
workers compensation insurance company say?

Slide 23:
Question 8

* In what way does the Social Security Administration (SSA) explicitly incorporate the role of the 
environment in their disability determination process?  [Hint: It is not very explicit or expansive.]

	- Possible Answer: Whether there exists a job in the national economy for which the applicant 
	can do with a reasonable degree of retaining.

Slide 24:
Question 9

* Suppose the Social Security Administration (SSA) codified the entire ICF within their disability 
determination process.  What implications do you think this would have for SSA policy and recent 
efforts of SSA to return to work?

	- Possible Answer: It might motivate SSA to work to address environmental barriers to 
	employment and other activities.

Slide 25:
Question 10

* What currently causes labor lawyers (representing both people with disabilities and employers) a great 
deal of uncertainty? 

	- Possible Answer: Based on my discussions with a few labor lawyers -- the lack of a clear definition of 
	disability. 

Slide 26:
Contact Information

Andrew J. Houtenville, Ph.D., Senior Research Associate
Employment and Disability Institute
School of Industrial & Labor Relations
Cornell University 
Room 331, Ives Hall
Ithaca, New York  14853-3901 USA 
Telephone: (607) 255-5702
TTY/TDD: (607) 255-2891 
Fax: (607) 255-2763
E-mail: ajh29@cornell.edu 
http://www.ilr.cornell.edu/RRTC/

http://www.disabilitystatistics.org