The WG has recommended a short list of six questions to be included in household surveys or censuses to <mark>capture respondents’ self-evaluation.</mark> They are presented in Box 1. The questions ask about difficulties in six domains: (a) seeing (even when wearing glasses), (b) hearing (even when wearing a hearing aid), (c) walking/climbing steps, (d) concentrating or remembering things, (e) self-care and (f) communication. The six domains cover four <mark>functional difficulties (seeing, hearing,</mark> concentrating/remembering, <mark>communicating) and two activity limitations (walking and self-care). For simplicity and brevity, we refer to them all as functional difficulties.</mark> For each difficulty, individuals respond on a scale of 1 to 4 as follows: 1 - no difficulty, 2 - some difficulty, 3 – a lot of difficulty and 4 - unable to do. The WGSS has the advantage of brevity and international comparability. Albeit cognitively tested in 14 countries (Miller 2016), these questions on functional difficulties are not without limitations. For instance, an understanding of functional difficulties may be limited in a context with limited access to health care (Schneider 2016). This may lead to underreporting in the countries under study. The WGSS covers few domains and may well under-identify people with certain difficulties, including psychological ones. This concern is alleviated in the WGSS-Enhanced, which is the short set plus four questions on anxiety and depression and two on upper body mobility and in the WG Extended Set on Functioning (WG ES-F), which includes questions that address functioning in domains such as upper body (functioning of the arms, hands and fingers), affect (anxiety and depression), pain and fatigue (e.g. Loeb 2016).

# **Box 1: Washington Group Short Set of Questions on Disability**

The next questions ask about difficulties you may have doing certain activities because of a health problem.

- (a)  Do you have difficulty seeing even if wearing glasses?

- (b)  Do you have difficulty hearing even if using a hearing aid?

- (c)  Do you have difficulty walking or climbing steps?

- (d)  Do you have difficulty remembering or concentrating?

- (e)  Do you have difficulty with self-care such as washing all over or dressing?

- (f) Using your usual language, do you have difficulty communicating, for example understanding or being understood?

For each question, respondents are asked to answer with one of the following options: 1-no difficulty, 2-some difficulty, 3-a lot of difficulty, or 4-unable to do.

For a proxy respondent, each of the six questions starts with “does <person > have difficulty...?” - <u>Source: http://www.washingtongroup disability.com/</u> While the WG recommends that the WGSS be adopted as is, some data sets have included selected questions only, changed the answer scale or the wording of questions. There are thus data sets that have questions somewhat similar to the WGSS. As shown in Table 2.1, 12 data sets under study have the WGSS, while 12 data sets have other functional difficulty questions that fulfill the United Nations principles and guidelines for censuses on disability (United Nations 2017, p. 207) in that they cover at least the four essential domains. The ways in which these 12 6