Environmental influences on the cumulative structure of instrumental ADL: an example in osteoporosis patients in a Swedish rural district

Introduction: The ADL Staircase is a hierarchical instrument for the assessment of dependence/independence in personal and instrumental activities of daily living (P-ADL and I-ADL). Previous results indicated that environmental factors might affect assessment results, and revisions for use in rural areas have been tested with a gerontological population sample. Objective: To investigate further the cumulative structure of I-ADL in osteoporosis patients in a Swedish rural district. Method: Patients were interviewed consecutively concerning their pre-injury dependence in P-ADL and I-ADL, using a revised version of the ADL Staircase (n = 276). Results: In contrast to results from urban areas, 'transportation' was the activity generating the most dependence among the respondents. In addition, different gender-specific cumulative orders among I-ADL were demonstrated. Guttman's scaling analysis confirmed the cumulativity of the revised scale (C of R = 0.94/0.97, C of S = 0.77/0.88). Conclusion: Environmental factors influence the validity of instruments as well as the prevalence of disability.