Perceptions of Older People Regarding Their Vision and Incident Causation.

PURPOSE: It is widely known that visual impairment (VI) is a risk factor for falls, but patients or their eye care practitioners may not recognize other kinds of incidents as being problematic because of their vision. Consequently, older people with VI may have unmet needs for advice on how to carry out activities of daily living safely. Therefore, the purpose of this study was to understand whether older people with VI consider their vision as a causative factor of incidents they experience and their perceptions regarding the prevention of future incidents. If sample size permitted, a secondary aim was to evaluate whether quantitative findings supported their perceptions. METHODS: The study design was a prospective cohort study evaluating injurious and damaging incidents and related near misses using open questions in a written 2-weekly large-print diary with active follow-up over 8 weeks in older people (>60 years, n = 80) with and without VI. Baseline measures included habitual binocular visual acuity, contrast sensitivity, visual fields, 3-m walk test, and Short Form 12 physical and mental component scores. Participants' diary entries were coded. Factor analysis and binary logistic analysis were used to investigate whether baseline measures were predictive of incident occurrence. Risk and preventative factors identified were compared. RESULTS: Participants perceived that their vision was implicated in bump and fall incidents. Quantitative analysis indicated that contrast sensitivity and fitness were significant predictors of incident occurrence. Six vision-related and five non-vision-related causative factors were identified by participants as contributing factors. Participants frequently stated "don't know" when asked to identify solutions to prevent incident recurrence. CONCLUSIONS: Participants had unmet needs for advice in relation to incident prevention. It would be prudent for eye care practitioners to raise incident prevention in eye care consultations regardless of voiced patient concerns.

Future fitness and helping in social queues.

Helpers in primitively eusocial and cooperatively breeding animal societies forfeit their own reproduction to rear the offspring of a queen or breeding pair, but may eventually attain breeding status themselves. Kin selection provides a widely accepted theoretical framework for understanding these societies, but differences in genetic relatedness do not explain a universal societal feature: the huge variation between individuals in helping effort. An alternative explanation for this variation lies in a fundamental trade-off faced by helpers: by working harder, they increase the indirect component of their fitness, but simultaneously decrease their own future survival and fecundity. Here, we show that individuals work less hard when they stand to lose more future fitness through working. We experimentally manipulated two components of future fitness in social queues of hover wasps (Stenogastrinae): a helper's chance of inheriting an egg-laying position, and the workforce available to rear her offspring should she inherit. After each manipulation, helpers increased or decreased their effort as appropriate to the change in expected future fitness that they experienced. Although helping provides significant indirect fitness benefits for hover wasps, our study shows that variation in the costs associated with helping is the major determinant of helping effort.

Luminance contrast preferences of people with a vision impairment for elements in the built environment.

BACKGROUND: Standards for building elements recommend a minimum luminance contrast of 30%. The basis of this value and the metric originally used is not known. OBJECTIVE: To begin to provide an evidence base for the specification of minimum contrast in building elements. METHODS: Subjects with and without a vision impairment were characterized by visual acuity, contrast sensitivity, visual fields and color vision. On an iPad they rated the visibility, as a function of contrast, of simulated door frames, door handles, light switches and stair nosings as "not visible at all", "poorly visible", "easily visible" and "extremely easily visible". RESULTS: The contrasts for each level of visibility were highly correlated with visual acuity and contrast sensitivity. A principal component analysis also verified the importance of visual acuity, contrast sensitivity and visual fields in rating visibility of simulations of building elements. The required contrast for door handles, light switches and stair nosings to attain the same ratings of visibility were very similar but less contrast was required for door frames. CONCLUSIONS: 30% Michelson contrast for building elements renders building elements only poorly visible for those with severe vision impairments. 65% luminance contrast is necessary for all elements to be "easily visible". Some increase (not a decrease) on the present 30% requirement and encouragement to exceed this requirement would seem appropriate. The use of simulated objects facilitates a systematic examination of the effect of contrast, but the applicability of the results to real-life remains to be demonstrated.

Issues in specifying contrast in building elements for people with a visual disability.

BACKGROUND: Standards writers, national and international, have used different contrast calculations to set requirements in building elements for people with visual impairments. On the other hand, they have typically set a single requirement (30%) for specifying the minimum contrast. The systems are not linearly related and 30% means something rather different in each system. OBJECTIVE: To provide a comparison of the various scales in order to illustrate the differences caused by multiple scales with a single compliance value, recommend a single scale for universal adoption and, if a new measure is problematic for implementation, to recommend the most perceptually uniform of the present methods. METHODS: We use the contrast between combinations of 205 paint colours to illustrate the relationships between the measures. We use an internationally accepted scale, with equal perceptual steps, as a "gold standard" to identify the most perceptually uniform measurement scale in the existing methods. RESULTS: We show that Michelson contrast is the most perceptually uniform of the existing measurement scales. We show the contrasts in the proposed method that equate to the various current requirements. CONCLUSIONS: We propose that CIE Metric Lightness could be used as the contrast measure. Alternatively, Michelson contrast is the most perceptually linear of the current measurement scales.

Housing Design and Community Care: How Home Modifications Reduce Care Needs of Older People and People with Disability.

The extent to which housing design can minimise levels of community caregiving has remained largely unmeasured. This paper reports the potential for home modifications to reduce caregiving in the peoples' homes, particularly older people and people with a disability. It contributes to new knowledge in understanding how housing can play a role in community caregiving and acknowledges the role of the built environment in managing care levels in ageing societies. This paper analyses self-reported care data from 157 Australian community care recipients (average age: 72 years) who had received home modifications within the past 6 months. A before/after comparison of care provided revealed that home modifications reduced hours of care provided by 42% per week. More detailed analysis revealed that the positive association of home modifications with care reduction is stronger with informal care (46% reduction) followed by formal care (16% reduction). These results suggest the role that home modifications, and housing design in general, play in reducing care needs in a community setting.

Transforming Inclusion: Designing in the Experience of Greater Technological Possibility.

Universal Design seeks to contribute to the sustainability and inclusivity of communities and co-design and participatory methods are a critical tool in this evolution. The fact that technology permeates our society is undeniable and the form and materials that technology takes in turn shape the basics of human life such as being able to shower and toilet oneself. In contrast, the various existing approaches to co-design have very different sorts of metaphysical, epistemological and normative assumptions behind them. As a result, design has recognised a set of problems surrounding the position of the "user" in design innovation. Additionally, there are many different perspectives on technology and the role of technology in co-design methods. Consequently, there are a number of different ways of conceiving of the "problem" of integrating technologies into co-design methods. Traditionally, participatory design has been viewed as merely the insertion of a more public dialog of the potential target market within technological design practices. Our research indicates that most if not all co-designers rely on their own personal and collective knowledge and experience and that if this is not actively explored as a part of a co-design methodology that both participation and innovation will be less than hoped for. For instance, assuming only known fixtures, fittings with current codes and standards is unlikely to result in product innovation.

Cryptic plasticity underlies a major evolutionary transition.

The origin of eusociality is often regarded as a change of macroevolutionary proportions [1, 2]. Its hallmark is a reproductive division of labor between the members of a society: some individuals ("helpers" or "workers") forfeit their own reproduction to rear offspring of others ("queens"). In the Hymenoptera (ants, bees, wasps), there have been many transitions in both directions between solitary nesting and sociality [2-5]. How have such transitions occurred? One possibility is that multiple transitions represent repeated evolutionary gains and losses of the traits underpinning sociality. A second possibility, however, is that once sociality has evolved, subsequent transitions represent selection at just one or a small number of loci controlling developmental switches between preexisting alternative phenotypes [2, 6]. We might then expect transitional populations that can express either sociality or solitary nesting, depending on environmental conditions. Here, we use field transplants to directly induce transitions in British and Irish populations of the sweat bee Halictus rubicundus. Individual variation in social phenotype was linked to time available for offspring production, and to the genetic benefits of sociality, suggesting that helping was not simply misplaced parental care [7]. We thereby demonstrate that sociality itself can be truly plastic in a hymenopteran.