An Explanation of the Washington Group Short Set of Questions on Disability

Better information on the experiences of disabled people assists policy and practice planning.

Washington Group on Disability Statistics

The Washington Group on Disability Statistics is a voluntary working group comprising representatives of over 100 National Statistical Offices and international non-governmental and disability organisations, organised under the aegis of the United Nations Statistical Division.

The primary purpose of the Washington Group is to focus on the challenge of defining disability and measuring disability in a way that is culturally neutral and reasonably standardised among the United Nations member states. Using measures that are minimally influenced by culture and context optimises the possibility of international comparisons by capturing comparable populations across countries.

The work of the Washington Group, which first met in 2002, has become increasingly important since the United Nations Convention on the Rights of Persons with Disabilities (CRPD) came into force in 2008. Article 31 of the CRPD obliges State Parties “to collect appropriate information, including statistical and research data, to enable them to formulate and implement policies to give effect to the present Convention.”

International Classification of Functioning, Disability and Health

In 2002, the Washington Group agreed to use the International Classification of Functioning, Disability and Health (ICF), developed by the World Health Organisation, as the framework for conceptualising/defining disability and for use in disability measurement.

The ICF provides a framework for conceptualising and classifying disability. The focus is on the individual’s ability to function within an environment (whether physical, social or attitudinal), as opposed to focusing on the presence of disease (e.g. a medical diagnosis) or self-identification as “disabled” (e.g. identifying disabled people as a cultural group with a unique identity).

The ICF diagram, shown below, lays out various types of functioning:

  • body functions (e.g. walking, hearing)
  • daily activities undertaken by an individual (e.g. climbing steps), and
  • an individual’s participation in any area of society (e.g. paid employment).

In addition, the ICF focuses on how the relationship between these three types of functioning is influenced by:

  • environmental factors (e.g. inaccessible transportation and public buildings, negative attitudes, limited social supports), and
  • personal factors (e.g. behavioural patterns). 
    Figure 1: Interaction between the components of the ICFFigure 1: Interaction between the components of the ICF

The ICF approach to disability can be aptly described as a bio-psycho-social model, given that it takes into account impairments in body function, limitations in carrying out everyday tasks and restrictions to participating in a range of areas of society. In other words, the ICF defines disability as an umbrella term for impairments, activity limitations and participation restrictions.

So the ICF has provided a framework to conceptualise and classify disability by focusing on: body function and structure, activity, participation and environment. The piece that is missing is a measurement instrument to identify a person as disabled.  The Washington Group Short Set of Questions on Disability (WGSS) is a measurement instrument that addresses this gap.

Washington Group Short Set of Questions on Disability

Purpose

It is important to note that the WGSS has been designed to focus on one aspect of the ICF, that is, to identify individuals who are at greater risk than the general population of experiencing restricted social participation because of difficulties undertaking basic activities. The purpose underpinning disability measurement in the WGSS is to see whether there is equality of opportunity in society for people with and without impairments in carrying out everyday activities.

The WGSS has been developed for use in censuses and sample-based national surveys (that are not disability specific). The format of data collection in these types of population surveys dictates that only a restricted number of additional questions can be included. Hence, there are only six questions in the WGSS, and these are not designed to:

  • estimate prevalence of disability
  • determine the need for services or interventions that can improve the lives of disabled people
  • identify people with mental health issues, or
  • identify children with impairments.

List of questions

The six questions that comprise the WGSS are listed below. These questions focus on six core functional domains: seeing, hearing, walking, cognition, self-care and communication.

  1. Do you have difficulty seeing, even if wearing glasses?
  2. Do you have difficulty hearing, even if using a hearing aid?
  3. Do you have difficulty walking or climbing steps?
  4. Do you have difficulty remembering or concentrating?
  5. Do you have difficulty (with self-care such as) washing all over or dressing?
  6. Using your usual (customary) language, do you have difficulty communicating, for example understanding or being understood? 

Response scales 
a. No - no difficulty 
b. Yes – some difficulty 
c. Yes – a lot of difficulty 
d. Cannot do at all 

Different thresholds can be used to derive disability status from the questions. The Washington Group recommends a threshold that requires individuals to have “a lot of difficulty” undertaking at least one of the activities in order to be identified as “disabled”.

Inclusion of Washington Group Short Set of Questions on Disability in regular New Zealand household surveys

The WGSS was included for the first time in the General Social Survey (GSS) for the 2016/17 collection year. This survey reports on well-being, and the survey results will be released in July 2017. The WGSS questions will continue to be included in the GSS which is run every two years.

The WGSS was also included for the first time in the June 2017 quarter of the Household Labour Force Survey (HLFS), and will continue to be included in each June quarter of the HLFS going forward.

The inclusion of the WGSS every two years in the GSS and in each June quarter of the HLFS will make it possible to track changes or trends in the lives of disabled people, compared with non-disabled people, over time. 
The WGSS has also been tested for inclusion in the 2018 Census. The final decision on whether the WGSS is to be included is expected to be announced at the end of July 2017 when Stats NZ will publish a paper on the content of the 2018 Census.

Relevance of Washington Group Short Set of Questions on Disability to the New Zealand Disability Strategy Outcomes Framework

The focus of the New Zealand Disability Strategy Outcomes Framework work is the development of a set of valid and reliable population-level indicators that are specific, observable and measurable, and can be tracked over time to show what change or progress is occurring against the Strategy’s eight outcome domains.

Data will be required to measure the indicators selected for each of the outcome domains. The inclusion of the WGSS every two years in the GSS and in each June quarter of the HLFS will, potentially, provide valuable data for the measurement of the indicators for each of the Strategy’s outcome domains.