Wednesday, May 19, 2010

Disability Prevalence -- Where Are We?

This post summarizes the general flow of my posts on disabilities over the past half-year.  I still have a few more posts in draft form, and I'll be wrapping those up shortly, but this is a good point at which to sketch out the picture as it has developed in this blog.

This post originated as an e-mail message to a researcher who seemed potentially interested in looking into data on disabilities.  I wanted to summarize, for him, the questions I have been studying.  As the message grew longer and began to cite my other blog posts, I realized that I should probably just put it up on the blog and refer him to it.  So what was going to be an e-mail message has now become the following paragraphs.

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Let me describe the situation in general terms, and see if there are particular aspects of it that seem to have the best potential for further investigation from a research perspective.  I tend to be somewhat philosophically oriented, so my apologies in advance if it takes me a while to reach the ground.

What the Question Is

The general question is, how many people have disabilities?  There is a definitional aspect to that question.  Speaking strictly from my own perspective, I have posted some blog entries about such matters.  This definitional question matters in the sense that, if we make the circle too small, we deny relevant assistance to people who need it.  An example, in the area of mental disability, is a person who does not qualify for an official psychiatric diagnosis but nonetheless experiences obvious difficulty.

That general question is operationalized in various surveys.  At this level, we move from the purely conceptual to a mix of the hypothetical and the actual.  Elsewhere, I have cited references to a so-called National Disability Data System (NDDS).  The NDDS itself does not exist formally; the concept is that it exists in effect, through the data provided by actual research efforts.   This is still an academic's discussion; at this level we are kicking around various ways of going at the question of disability prevalence.

From there, we move to a more concrete level.  This is the level at which politicians and the public are given specific numbers.  They may not be the right numbers, but that's what footnotes are for.  Most notably, the American Community Survey (ACS) replaces the decennial census; that is, questions about disabilities have disappeared from the latter because the prevalence of disabilities is now being estimated rather than counted.  The ACS is in the process of replacing the census, for this purpose, down to the local level.

Why It Matters

As you can see, I have been trying to get a grasp on what we think we know, and why we think we know it.  But why does it matter?  Why should we care about the prevalence of disabilities?  There seem to be two ways to answer that.

The National Perspective

On one hand, we can approach the issue from a national perspective.  As the posts describe, the disability-related questions on the ACS have been modified, in the last few years, for purposes of improved reliability.  All well and good; but in the process, the estimate of people with disabilities dropped by some 15%.  Meanwhile, more sensitive measures (e.g., the SIPP) have the potential (but, alas, not the financial backing) to show a significantly higher rate.

The nation has a profound interest, budgetary and otherwise, in knowing whether the number of people with disabilities is 38 million or, instead, 53 million (to cite one alternate figure that I have encountered).  A million people here, a million people there, and pretty soon we're talking about real people.  The estimates are definitionally driven, of course, but that's the point:  how much higher does the prevalence rate go if the researcher uses a different, but comparably respectable, definition?

For example:  in an interesting book, Bagenstos contends that the Americans with Disabilities Act (ADA) has been developed in the direction of treating disability as a minority-rights kind of issue.  This, he says, has had the advantage of drawing upon the legacy of civil rights movements of the 1960s and 1970s, thus giving disability rights advocates a certain automatic sense of legitimacy.  The drawback has been that such movements invite opposition from those whom they exclude, particularly if the latter are expected to pay for adjustments to rectify perceived wrongs.

The alternative, Bagenstos says, is to treat the condition in question -- disability, in this case -- as a universal issue, something in which everyone partakes, or is at risk of partaking, through various forms of inability and imperfection.  In this approach, disability prevalence can be calculated without segregating "people with disabilities" into their own conceptual ghetto.  If disability is treated as something that anyone is capable of experiencing, like chickenpox or the flu, but if only a fraction of the population is likely to experience it at any particular point, what is that fraction?

Good question.  But how can we answer it?  The budgetary infeasibility of extending the SIPP to localities across the entire nation, on a par with the ACS, demonstrates that national disability prevalence estimation is presently stuck in a rather absurd place.  Because of its lack of local foundation, it can be gerrymandered, from a desk in D.C., to add or drop five or ten million people here and there, for reasons of statistical or budgetary convenience.  The nation, and the disability community, need something better than that.  The following suggestion illustrates a national alternative on the local level.

The Local Perspective

The relatively narrow operationalization of disability in the ACS is obviously problematic.  If its national estimate of disabilities is on the conservative side, its local estimate will tend to be so as well.

That seems reasonable enough.  But putting it that way highlights a bigger problem.  The idea seems to be that the best way to know whether my neighbor has a disability is to wait for the latest ACS to be completed; wait for the local-level ACS data to be compiled by someone in Washington; adjust that local number upwards by a fudge factor due to the conservative bias of the ACS; and then calculate my neighbor's odds.

Faced with that kind of logic, practical decisionmakers and advocates say, in effect, "Research be damned."  They aren't going to plumb the intricacies of the Supreme Court's latest interpretations of the Americans with Disabilities Act, and they aren't going to invest the time required for a clear understanding of the ACS.  They're going to rely, instead, on what they've heard and what they believe, supplemented by the occasional citation to some source or other.

Suppose we began, instead, from present experience.  Suppose, for example, that I cannot walk to work.  Research on the benefits of outdoor exposure suggests that this state of affairs will tend to make me less happy than I would be if I could walk to work.  The reason for this impairment of my subjective well-being may not be crucial:  it may not matter, for that purpose, whether I can't walk to work because I have no legs or, instead, because the streets between here and there are dangerous for pedestrians.  Either way, I can't do it.

The focus, in that example, is upon achieving a certain outcome.  Outcome-oriented disability estimation is, in essence, the language of actual local life.  The mayor finds that 39% of her constituents are furious about the state of the roads.  They are experiencing some transportation-related disability.  The fact that 3% of constituents are furious about the state of the sidewalks may be politically trivial, but a transportation-related disability nonetheless exists there as well.

Improved accessibility will often be politically infeasible if the public impression is that we are trying to spend a fortune on curb cuts for a small number of people in wheelchairs who never use the sidewalks anyway.  Rather than ask for special handouts, a more defensible view of transportation-related disability would focus on getting the roads and sidewalks into shape for people on foot, in wheelchairs, and in cars.  Infrastructure is essential.  Everyone needs effective transportation.


Disability has been defined in different ways.  A cursory review suggests that American law is presently oriented toward treating a disability as a flaw in the individual.  Hence, instruments like the ACS look for vision impairments and other personal characteristics that prevent people from functioning like everybody else.  The social model of disability is incorporated only in the limited sense that some survey questions acknowledge, in various ways, that disability may entail mismatch between person and society; yet even that acknowledgement inevitably brings the focus back to the individual.

That approach to disability has the potential to get everyone bogged down in mutual recrimination, with the familiar old vocabularies of "handouts" versus "privilege," and "normal people" versus "the oppressed."  An approach that could be more readily calculated on the local level, and more consistent and politically supportable on the national level, would focus upon desired life outcomes.

Using transportation as a particularly important disability-related outcome, one can ask how many people are not able to get where they need to go within a reasonable amount of time, in a reasonable manner, at reasonable cost.  There are many kinds of transportation-related disabilities in this sense.  Here are some examples:
  • People who are disabled from independent transportation because they are under the control of others.  Examples include children and prison inmates.  
  • Those whose health precludes independent travel -- hospital inpatients, for instance, and nursing home residents.
  • People may also be economically disabled from utilizing independent transportation:  for instance, they may not have money for a car or even for bus fare, assuming there is a bus line near them.
  • People whose obligations prevent independent travel:  people have to stay at work, or have to stay near a certain location to be available for work, or have to stay home with the kids or with a sick relative.
  • Social disability precluding independent transportation.  People are stared at and harassed if they are someplace where, in effect, they don't belong.  This can include kids in the vicinity of a bully, women who are out late alone, bicyclists on a busy street, individuals of an unfamiliar or unwelcome race, and people who dress funny or act funny.
The purpose of such an investigation would be to provide an alternative perspective that would be more immediately familiar to the public and more responsive to actual human experiences of disability.  The idea is that, for whatever reason, some people can't get where they need to go.

Needless to say, this post does not purport to address the gamut of disability-related concerns and issues.  Indeed, it is precisely not that sort of thing.  What I have observed, in my half-year of exposure to disability-related matters, is that the cerebral model of disability -- the one that begins with abstract, individual-oriented definitions and works its way down to concrete application -- is not really very practical.

It tentatively seems that it would be more useful, marketable, and appropriate to treat disability as a matter of sociopersonal constraints that everyone experiences in various forms, and to focus especially upon those global, national, state, and/or local conditions that most profoundly impair the achievement of the most important outcomes.  This approach would still prioritize many individual impairments, but would do so as a matter of an investment in society's future rather than as a handout to a person who has managed to become privileged in the eyes of the law.