Dr. Daniel Mont. 23 January 2017
The social model of disability was groundbreaking in its view of people with disabilities. Disability is not the same as an impairment, but emerges through the interaction of a person’s functional ability with their environment. People aren’t disabled because they can’t move their legs. They are disabled because they live in an inaccessible environment, without access to assistive devices, in a world where they can also face discrimination. The social model, embodied in the Convention on the Rights of Persons with Disabilities, also informed the development of the WHO’s International Classification of Functioning, Disability and Health (ICF). The famous ICF diagram, shown below, lays out various types of functioning (body function, activities, and participation) and how the relationship among them is influenced by environmental barriers, be they at the micro-, meso-, or macro-level. This conception of disability is important because it demonstrates how policies can be created that will achieve a totally inclusive environment as opposed to policies that attempt to prevent impairments or provide charity to those who are excluded from the social and economic life of their communities.
To develop, monitor, and evaluate these policies we need high quality data that allow us to examine all the concepts embodied in the boxes and arrows of this diagram. The challenge is, how do we do this? Disability is a very complex concept. It is more than impairment or problems in body function and structure. Not only are there different types and degrees of both disability, but for a full understanding of the lives of people with disabilities we need to be able to see how the concepts in the ICF boxes interact with each other to create the lived reality of people with disabilities.
This proposes a challenge for quantitative analysis. In fact, the ICF diagram with its many boxes and arrows going in both directions can be characterized as a statistician’s nightmare. The reason is that the questions used on surveys or censuses to collect quantitative data must be very specific and precise, focusing in on a single concept so that the full range of respondents interpret and answer those questions in a consistent and common manner. Questions that do not meet this requirement will not produce high quality, useful data.
Consider this question,
Do you have a health-related impairment that, because of barriers you face in your environment, limits the amount or type of work that you can do?
This question attempts to encapsulate the ICF. For a few reasons, it is not a good question for a quantitative data instrument. First, the question is difficult to understand and will not be answered the same by different people. What is a health-related impairment? Would someone whose disability arises from aging consider their difficulties walking a health-related impairment? What is meant by the environment – the physical environment, the institutional environment, the cultural environment? Will people interpret the word “barriers” similarly depending on their background or cultural milieu? How will a person combine all of the ideas expressed in this extremely complicated question.
The rather complex question above also does not allow the user to disentangle the relationship between activities (such as hearing) from participation (such as working), in regards to potential barriers. A person might answer ‘no’ because they have no impairment or they might answer ‘no’ because they face no barriers to participation. The distinction is very important for policy analysis. Let’s say that in the five years between two surveys fewer people answer ‘yes’ to this question. What has happened? Has the prevalence of impairments lessened, or has society become more inclusive? We won’t know.
Good survey questions, therefore, attempt to hone in on very specific concepts. For example, the Washington Group Short Set on Functioning (WG SS) ask specifically about difficulties in undertaking basic, universal activities in a specific set of core domains. Occasionally, disability advocates have objected to these questions. They think that the WG SS represents the medical model because it does not ask about participation or environmental barriers. They think it excludes those concepts.
Now, it is true that the specific questions in the WG SS do not directly address participation and environment. Rather, the questions obtain information on one aspect of the ICF (basic activity limitations), to identify those at risk of restricted participation in an unaccommodating environment. The questions were designed to be added to censuses and surveys that obtain information the other concepts in the social model, that is, data on other concepts in the ICF diagram. Information on the environment and participation can be obtained and from other questions in a survey that includes the WG SS. Using the WG SS and these other questions together, we can measure the strength of the various associations (the arrows in the diagram) through the analysis of the data.
For example, if we compare the employment rates (a measure of participation obtained in the census or survey) of people with and without disability (as obtained from the Washington Group questions), we can find evidence for the existence of environmental barriers. If people of the same age, gender, area of residence, etc. who have difficulty seeing have lower employment rates than similar people with no difficulty seeing, then the conclusion is that barriers must exit for people with seeing difficulties. If we find that those differences disappear when comparing people with the same level of education (as well as age, gender, region of residence, etc.), then the analysis would suggest that while people with vision difficulties face barriers to education, they don’t face barriers to employment if they manage to get that education. This is not to say this is the reality. It is only a hypothetical example of how analyzing data can reveal patterns that give insight into the nature of the barriers faced by people with disabilities.
If we want to get at the nature of the barriers we must ask about them directly. Do you have difficulty using public transportation? Are their sign language interpreters available to you? And so forth.
And even here, when we ask about the reasons for non-participation, we should not ask if it is because of a disability, because that does not give us specific information that is useful for policy development. Consider the following question:
Why are you not employed?
- No jobs available in my area
- I don’t have enough education
- Problems with transportation
- Workplaces are not accessible
- I have a disability
What if someone is not employed because they don’t have accessible transportation? They may answer c) or they may answer e) because if they did not have a disability then transportation would not be an issue. The fact that two people in the same situation might very well answer differently will give us inconsistent data. But what if everyone in this situation answered e)? Would that tell us what the barriers are? It could be because people with disabilities don’t have access to education. It could be because they don’t have access to transportation, or maybe transportation is accessible but workplaces are not. If all we know is e) – that they have a disability – it does not direct us to what would be the most effective policy responses.
Instead we want separate information on activity limitations and reasons for not working. Then, we could see that maybe people without activity limitations never have a problem with transportation but people with activity limitations do have problems. This would give us evidence that inaccessible transportation is a barrier.
The bottom line is that good quantitative analysis that allows us to get a complex picture of the relationship between all the concepts in the ICF, or the social model of disability, requires the collection of the specific components of that model. The WG SS is designed to address a particular box of the ICF for a particular purpose – to see if there are equality of opportunities for people with and without difficulties in undertaking basic activities. As explained in more detail on this website under the “purpose of the WG questions”
So don’t look at question in isolation! Look to see if questions are well-designed and tested, to ensure that as much as possible they identify a particular concept in a consistent manner. Then, make sure that data on enough of these concepts are collected to allow analysis that can provide useful information to answer the important questions at hand.