Additional table 1 Linking the items of the DHI to ICF-categories

4 3 Item Questions ICF-labels ICF- F F categories 1 1 E 23 Because of your problem, are you depressed? emotional functions b152 1 1 E 2 Because of your problem, do you feel frustrated? emotional functions b152 1 1 F 24 Does your problem interfere with your job or household responsibilities? remunerative employment; d850 doing housework d640 1 1 E 21 Because of your problem, do you feel handicapped? orientation to self; b11420 experience of self and time functions b180 1 1 E 10 Because of your problem, have you been embarrassed in front of emotional functions; b152 others? societal attitudes e460 1 1 F 6 Does your problem significantly restrict your participation in social recreation and leisure d920 activities such as going out to dinner, going to movies, dancing, or to parties? 1 1 E 22 Has your problem placed stress on your relationship with members of family relationships; d760 your family or friends? informal social relationship d750 1 1 F 3 Because of your problem, do you restrict your travel for business or using transportation; d470 recreation? driving d475 1 1 E 18 Because of your problem, is it difficult for you to concentrate? focusing attention d160 2 2 P 13 Does turning over in bed increase your problem? changing basic body position d410 2 2 F 5 Because of your problem, do you have difficulty getting into or out of lying down d4100 bed? 2 2 P 1 Does looking up increase your problem? watching d110 2 2 P 11 Do quick movements of your head increase your problem? control of voluntary movement functions; b760 structures of head and neck s710 2 2 P 25 Does bending over increase your problem? bending d4105 2 2 F 7 Because of your problem, do you have difficulty reading? reading d166 3 3 P 17 Does walking down a sidewalk increase your problem? moving around outside the home and other buildings; d4602 natural environment and human-made changes to environment e298 3 3 F 19 Because of your problem, is it difficult for you to walk around your house moving around within the home; d4600 in the dark? light e240 3 3 E 15 Because of your problem, are you afraid people may think you are emotional functions; b152 intoxicated? vestibular functions of balance; b2351 sensations associated with hearing and vestibular function; b240 societal attitudes e460

1 3 2 P 8 Does performing more ambitious activities like sports, dancing, sports; d9201 household chores increase your problem? doing housework; d640 coordination of voluntary movement; b7602 muscle power functions b730 3 3 P 4 Does walking down the aisle of a supermarket increase your problem? moving around within buildings other than home; d4601 design, construction and building products and technology of buildings for public use e150 3 3 F 12 Because of your problem, do you avoid heights? land forms; e2100 design, construction and building products and technology of buildings for public use e150 3 2 F 14 Because of your problem, is it difficult for you to do strenuous doing housework; d640 housework or yardwork? muscle power functions; b730 muscle endurance functions b740 4 3 E 20 Because of your problem, are you afraid to stay home alone? emotional functions; b152 personal care providers and personal assistants; e340 friends e320 4 3 E 9 Because of your problem, are you afraid to leave your home without emotional functions; b152 having someone accompany you? personal care providers and personal assistants; e340 friends e320 4 3 F 16 Because of your problem, is it difficult for you to go for a walk by Moving around outside the home and other d4602 yourself? buildings; personal assistants e340

Abbreviations: 3F, 4F, indicates the components belonging to the 3- respectively 4-factor solution of the principal component analysis. Bold face indicates the differences between the 3- respectively 4-factor solution. b- values of the International Classification of Functioning, Disability and Health (ICF) categorize body functions; d- values activities and participation; e- values environmental factors; s-values body structures. http://apps.who.int/classifications/icfbrowser/; 14.02.2010

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