I. Short Set (SS), Short Set-Enhanced (SS-E) and Extended Question (ES) Set on Functioning Questions (>17 years old) ^ A. Vision 1. Do you wear glasses? (Yes/No) 2. If yes, do you have difficulty seeing even when wearing your glasses? (No difficulty/Some difficulty/A lot of difficulty/Cannot do at all or unable to do) 3. If no, do you have difficulty seeing? (No difficulty/Some difficulty/A lot of difficulty/Cannot do at all or unable to do) B. Hearing 1. Do you wear a hearing aid? (Yes/No) 2. If yes, do you have difficulty hearing even when using a hearing aid? (No difficulty/Some difficulty/A lot of difficulty/Cannot do at all or unable to do 3. If no, do you have difficulty hearing? (No difficulty/Some difficulty/A lot of difficulty/Cannot do at all or unable to do) C. Mobility 1. * Do you use any equipment or receive help for getting around? (Yes/No) 2. * If yes, do you have difficulty walking or climbing steps, even when using your equipment or with help? (No difficulty/Some difficulty/A lot of difficulty/Cannot do at all or unable to do) 3. Do you have difficulty walking or climbing steps? (No difficulty/Some difficulty/A lot of difficulty/Cannot do at all or unable to do) D. Cognition 1. Do you have difficulty remembering or concentrating? (No difficulty/Some difficulty/A lot of difficulty/Cannot do at all or unable to do) II. Child Functioning Module (5–17 years old) and Child Functioning Module (2–4 years old) ^ A. Vision (same as above applied to the child and asked of the carer) B. Hearing (same as above applied to the child and asked of the carer) C. Mobility 1. ** Compared with children of the same age, does [name] have difficulty walking? 2. Does (name) use any equipment or receive assistance for walking? 3. Without his/her equipment or assistance, does [name] have difficulty walking 100 m on level ground? That would be about the length of one football field. 4. Without his/her equipment or assistance, does [name] have difficulty walking 500 m on level ground? That would be about the length of five football fields. 5. With his/her equipment or assistance, does [name] have difficulty walking 100 m on level ground? 6. With his/her equipment or assistance, does [name] have difficulty walking 500 m on level ground? 7. Compared with children of the same age, does [name] have difficulty walking 100 m on level ground? 8. Compared with children of the same age, does [name] have difficulty walking 500 m on level ground? ^ Subsets of full questionnaires; * Questions not asked in Turkey Disability and Mental Health Survey; ** Only question asked in Cameroon and India Disability Surveys, all other questions were asked in Turkey Disability and Mental Health Survey only.