Thus, we will assess agreement between the approaches, face and construct validity of the simple approach, and compare the predictive capacity of the 2 approaches using nursing home use (NHU), death, or both, as the primary outcome. The University of Pennsylvania institutional review board approved this study. The Second Longitudinal Study of Aging (LSOA II) was a nationally representative prospective cohort (N=9447) of community-dwelling persons, 70 years
Selleck BMS-354825 and older at baseline (Wave 1) in 1994. Wave 2 interviews occurred in 1997 and 1998, and the overall Wave 2 response rate was 84.7% (n=7998).13 The LSOA II asks 2 questions for each ADL (bathing/showering, dressing, eating, getting in and out of bed or chairs, walking, using the toilet including getting to the toilet) to determine ADL difficulty. The first question asks, Rapamycin solubility dmso “Because of a health or physical problem do you have ANY difficulty…?” An affirmative answer is followed by asking “how much difficulty,” which leads to 4 response levels (no, some, a lot, unable). Complex stages were developed using the 4-level responses.3 We used the first
question’s 2-level response (difficulty, no difficulty) to develop simple stages, using an empirical approach similar to that used in the complex system development.11 Complex ADL stage development has been described elsewhere,11 so we only present the development of simple stages. Each person was assigned an ADL profile based on the answers to the 6 ADL questions. Profiles were then sorted by the total number of reported difficult ADL (range, 0–6). The most frequent profile of those reporting 1 difficult ADL defined the “hardest” ADL. An additional criterion was that once an ADL entered the hierarchy, it had to remain difficult in the most frequently occurring profiles of higher totals of ADL difficulties. Hence, for each unit increase in total number of difficult ADL, only 1 ADL
was added, which was then considered enough the “next hardest” ADL (table 1). After determining the ADL hierarchy, we constructed 5 stages (see fig 2) to reflect the 5 International Classification of Functioning, Disability and Health self-care performance levels. We grouped the 2 hardest ADL, followed by the next 2 hardest ADL. Those reporting difficulty with all ADL were assigned stage IV. Stage III was designed to accommodate atypical patterns of difficulty where a person reported difficulty with 1 (or both) of the 2 easiest ADL, but no difficulty with at least 1 ADL (which often includes one of the harder ADL). After establishing the stages, we then developed algorithms (see figs 1 and 2) to facilitate assigning stages efficiently in a clinical setting.