Table 2 has the list of 46 countries, 68 data sets and 100 data set-years that have functional difficulty questions other than the WGSS. Such questions are, however, similar to the WGSS but with differences with respect to the answer scale, the domains, or the wording of the questions. The data sets in Table 2 vary greatly in how similar they are to the WGSS.

Regarding the answer scale, 16 data sets have a yes/no answer. Most of the data sets in Table 2 do not have all six domains of the WGSS. Many lack the self-care or the communication domain. Some data sets have domains beyond those in the WGSS (not shown in Table 2). Differences with the WGSS questions include, for instance, some reference to some _permanent limitation_ (e.g. Panama, Peru), and some added language. For instance, for South Africa (GHSM LCS, NHTS) the question pertaining to walking mentions _a kilometer_ and communicating with his/her usual language mentions _including sign language_ (emphasis added).

Results from Tables 1 and 2 are jointly represented in Figure 1, which is a map of countries with functional difficulty questions in their surveys or censuses. These could be the WGSS or other functional difficulty questions. Half of LMICs have functional difficulty questions in their surveys or censuses. In Europe/Central Asia and Sub-Saharan Africa, most countries do not have functional difficulty questions.

Appendixes 1 through 4 provide results for other types of disability questions noted in Section 2. Appendix 1 lists 15 countries and 24 data sets and 36 data set years that have ADL questions. Most countries with ADL questions are in Europe/Central Asia and Sub-Saharan Africa. As expected, surveys focused on older persons (e.g. CHARLS in China) have questions on ADL. While not shown in Appendix 1, there is heterogeneity in the ADL questions that are asked across countries with most often questions around physical basic activities such as walking over 100 meters, standing or sitting.

Appendix 2 includes 36 countries, 53 data sets and 76 data set-years with broad activity limitation questions. The most commonly found broad activity question asks about the person being limited in daily activities or in learning or in any economic activity due to a health problem in the past six months (not shown in Appendix 2). Some countries have several questions to get at broad activity limitations, including some recording the number of days the person was unable to carry out usual activities.

Appendix 3 has 50 countries, 81 data sets and 113 data set-years with a general disability question such as “does [Name] have a disability?” Often such questions are followed up with a question on the type of disability or the impairment the person has.

Appendix 4 has 43 countries, 54 data sets and 75 data set-years that have other types of disability questions such as belonging to the so-called disabled social group for Armenia.<sup>4</sup> In addition, some of the questions found in this list can be mixes of different types of questions such as impairments mixed with chronic health conditions in Tunisia, Bosnia, and Bulgaria. We have

> 4 Disability focused surveys (e.g. Philippines Model functioning Survey) were not covered in this table for other disability questions, but were covered in Tables 1 and 2 and Appendices 1, 2 and 3. Disability focused surveys typically have several types of other disability questions not beyond functional ADL, general and broad activity limitation questions.

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