Utility and validity of the self-administered SF-36: findings from an older population

<p><b>INTRODUCTION</b>The objectives of this study were to assess the utility and validity of the self-administered SF-36 and the effect of visual or cognitive impairment on these measures in an older population.</p><p><b>MATERIALS AND METHODS</b>Attempt rates, completion rates and internal consistency (Cronbach alpha) were compared within the second cross-sectional, population-based Blue Mountains Eye Study (n = 3509, mean age 66.7 years, 57% women).</p><p><b>RESULTS</b>The SF-36 was attempted by 3162 (90.1%) participants, of which 2470 (78.1%) completed all items and 2873 (90.9%) completed sufficient items for calculation of all dimensions. In a multivariate model adjusting for age, sex, and presenting visual and cognitive impairments, women (P = 0.011) and participants with visual or cognitive impairments (P < 0.0001) were less likely to attempt the questionnaire. Completion rates were significantly lower with increasing age (P < 0.0001), in men (P < or = 0.0005) and in those with cognitive impairment (P < 0.0001). A high level of internal consistency (Cronbach alpha > 0.85 for all dimensions) and construct validity was demonstrated, the latter distinguishing between those with and without medical conditions, disabilities or recent hospital admissions (P < 0.01). As the prevalence of visual or cognitive impairment was relatively low in this population, we found no apparent effect of these impairments on the validity of SF-36.</p><p><b>CONCLUSIONS</b>Attempt and completion rates, but not internal consistency and construct validity, of the SF-36 were influenced by age, gender, and presenting visual and cognitive impairments. The overall high attempt and completion rates, internal consistency and construct validity suggest that the self-administered SF-36 is a suitable healthrelated quality of life (HRQOL) measure in similar older community-living populations.</p>

Are sensory and cognitive declines associated in older persons seeking aged care services? Findings from a pilot study

<p><b>INTRODUCTION</b>To assess the association between sensory and cognitive function, and the potential influence of visual function on cognitive function assessment, in a sample of clients accessing aged care services.</p><p><b>MATERIALS AND METHODS</b>We recruited 260 non-institutionalised, frail, older individuals who sought aged care services. Visual acuity was assessed using a LogMAR chart and hearing function was measured using a portable pure-tone air conduction audiometer. Visual impairment was defined as visual acuity (VA) <6/12 (<39 letters read correctly in the better eye), moderate-to-severe hearing impairment as hearing thresholds >40 decibels (better ear) and cognitive impairment as Mini-Mental State Examination (MMSE) score <24.</p><p><b>RESULTS</b>Vision and hearing assessments were randomly performed in 168 and 164 aged care clients, respectively. Visual acuity correlated weakly with MMSE scores, either including (r = 0.27, P <0.001) or excluding (r = 0.21, P = 0.006) vision-related MMSE items. After partialling out the effect of age, the association remained (r = 0.23, P = 0.013 including, or r = 0.18, P = 0.044 excluding vision-related items). No correlation was found between MMSE scores and hearing thresholds (r = -0.07, P = 0.375). After adjusting for age, sex and stroke, mean MMSE scores were lower in persons with visual impairment than those with normal vision (25.2 + 0.5 versus 26.8 + 0.4 including, or 18.2 + 0.5 versus 19.2 + 0.3 excluding vision-related items), but were similar between subjects with none or mild and those with moderate-to-severe hearing loss (26.3 + 0.4 versus 26.0 + 0.4).</p><p><b>CONCLUSIONS</b>In this study sample, visual and cognitive functions were modestly associated, after excluding the influence of visual impairment on the MMSE assessment and adjusting for age. Hearing thresholds were not found to be associated with cognitive function.</p>

Variables determining perceived global health ranks: findings from a population-based study

<p><b>OBJECTIVE</b>To assess variables associated with different perceived global health ranks in an older population.</p><p><b>MATERIALS AND METHODS</b>The Blue Mountains Eye Study was a populationbased survey of residents aged >or=49 years in an area west of Sydney, Australia. Questions relating to demographic and socioeconomic indicators, limitations of daily living activities, medical history, hearing problems, exercise, smoking and alcohol consumption were asked in a standardised questionnaire at interview. Comprehensive eye examinations were performed. Self-rated health was assessed from a standard question and categorised as excellent, good, fair or poor. Associations were assessed using logistic regression models.</p><p><b>RESULTS</b>After exclusions, 714/3589 (19.9%) participants rated their health as excellent, 1969 (54.9%) as good, 766 (21.3%) as fair and 140 (3.9%) as poor. A wide array of study variables assessed showed significant associations with self-rated health. Compared with a self-ranking of good or excellent health, variables significantly associated in a multivariate model with a rank of poor health included: regular use of community support services, more than one hospital admission in the last 12 months, perceived inability to go out alone, difficulty walking, or history of angina, asthma or cancer. Variables significantly associated with a rank of fair health were broader and included socioeconomic status, sensory impairment, tinnitus, many chronic diseases and negative health behaviours, including smoking and heavy alcohol consumption.</p><p><b>CONCLUSIONS</b>Our findings suggest that different sets of variables may influence people to rank their global health at different perceived levels.</p>