Philippe F. Lacherez

A multidomain approach for predicting older driver safety under in-traffic road conditions

OBJECTIVES: To identify a battery of tests that predicts safe and unsafe performance on an on‐road assessment of driving.

Risk of Falls, Injurious Falls, and Other Injuries Resulting from Visual Impairment among Older Adults with Age-Related Macular Degeneration

PURPOSE Age-related macular degeneration (AMD) is the leading cause of irreversible visual impairment among older adults. This study explored the relationship between AMD, fall risk, and other injuries and identified visual risk factors for these adverse events. METHODS Participants included 76 community-dwelling individuals with a range of severity of AMD (mean age, 77.0 ± 6.9 years). Baseline assessment included binocular visual acuity, contrast sensitivity, and merged visual fields. Participants completed monthly falls and injury diaries for 1 year after the baseline assessment. RESULTS Overall, 74% of participants reported having either a fall or a non-fall-related injury. Fifty-four percent of participants reported a fall and 30% reported more than one fall; of the 102 falls reported, 63% resulted in an injury. Most occurred outdoors (52%), between late morning and late afternoon (61%) and when navigating on level ground (62%). The most common non-fall-related injuries were lacerations (36%) and collisions with an object (35%). Reduced contrast sensitivity and visual acuity were associated with increased fall rate, after controlling for age, sex, cognitive function, cataract severity, and self-reported physical function. Reduced contrast sensitivity was the only significant predictor of non-fall-related injuries. CONCLUSIONS Among older adults with AMD, increased visual impairment was significantly associated with an increased incidence of falls and other injuries. Reduced contrast sensitivity was significantly associated with both increased rates of falls and other injuries, while reduced visual acuity was only associated with increased fall rate. These findings have important implications for the assessment of visually impaired older adults.

Postural stability and gait among older adults with age-related maculopathy

PURPOSE To assess the postural stability and gait characteristics of adults with age-related maculopathy (ARM) and to identify the visual factors associated with postural stability and gait in this clinical population. METHODS Participants included 80 individuals with a range of severity of ARM (mean age, 77.2 years). Binocular visual function measures included visual acuity, contrast sensitivity, and merged binocular visual fields. Postural stability was assessed on both a firm and a foam surface using center-of-pressure measures derived from a force platform. Forty three of the participants underwent a three-dimensional motion analysis to quantify gait characteristics, including walking velocity, proportion of time spent with both feet in contact with the ground (double-support time), stride length, and step width. RESULTS After adjustment for age, sex, self-reported physical function, and cataract severity, all the vision measures were significantly associated with postural stability on the foam surface, with contrast sensitivity being the strongest correlate. In the analysis of the gait measures, only contrast sensitivity was significantly associated with walking velocity, step width, or stride length, whereas contrast sensitivity and visual field loss were both significantly associated with double-support time. CONCLUSIONS Impaired contrast sensitivity was associated with postural instability, slower walking velocity, increased step width, and reduced stride length. Impairments in either contrast sensitivity or visual fields were associated with increased double-support time. This result suggests that loss of contrast sensitivity and visual fields in patients with ARM can lead to balance and mobility problems.

The On-Road Difficulties of Older Drivers and Their Relationship with Self-Reported Motor Vehicle Crashes

OBJECTIVES: To quantify the driving difficulties of older adults using a detailed assessment of driving performance and to link this with self‐reported retrospective and prospective crashes.

Useful Field of View Predicts Driving in the Presence of Distracters

Purpose. The Useful Field of View (UFOV®) test has been shown to be highly effective in predicting crash risk among older adults. An important question which we examined in this study is whether this association is due to the ability of the UFOV to predict difficulties in attention-demanding driving situations that involve either visual or auditory distracters. Methods. Participants included 92 community-living adults (mean age 73.6 ± 5.4 years; range 65–88 years) who completed all three subtests of the UFOV involving assessment of visual processing speed (subtest 1), divided attention (subtest 2), and selective attention (subtest 3); driving safety risk was also classified using the UFOV scoring system. Driving performance was assessed separately on a closed-road circuit while driving under three conditions: no distracters, visual distracters, and auditory distracters. Driving outcome measures included road sign recognition, hazard detection, gap perception, time to complete the course, and performance on the distracter tasks. Results. Those rated as safe on the UFOV (safety rating categories 1 and 2), as well as those responding faster than the recommended cut-off on the selective attention subtest (350 msec), performed significantly better in terms of overall driving performance and also experienced less interference from distracters. Of the three UFOV subtests, the selective attention subtest best predicted overall driving performance in the presence of distracters. Conclusions. Older adults who were rated as higher risk on the UFOV, particularly on the selective attention subtest, demonstrated poorest driving performance in the presence of distracters. This finding suggests that the selective attention subtest of the UFOV may be differentially more effective in predicting driving difficulties in situations of divided attention which are commonly associated with crashes.

Using reflective clothing to enhance the conspicuity of bicyclists at night

Bicycling at night is more dangerous than in the daytime and poor conspicuity is likely to be a contributing factor. The use of reflective markings on a pedestrians major joints to facilitate the perception of biological motion has been shown to greatly enhance pedestrian conspicuity at night, but few corresponding data exist for bicyclists. Twelve younger and twelve older participants drove around a closed-road circuit at night and indicated when they first recognized a bicyclist who wore black clothing either alone, or together with a reflective bicycling vest, or a vest plus ankle and knee reflectors. The bicyclist pedalled in place on a bicycle that had either a static or flashing light, or no light on the handlebars. Bicyclist clothing significantly affected conspicuity; drivers responded to bicyclists wearing the vest plus ankle and knee reflectors at significantly longer distances than when the bicyclist wore the vest alone or black clothing without a vest. Older drivers responded to bicyclists less often and at shorter distances than younger drivers. The presence of a bicycle light, whether static or flashing, did not enhance the conspicuity of the bicyclist; this may result in bicyclists who use a bicycle light being overconfident of their own conspicuity at night. The implications of our findings are that ankle and knee markings are a simple and very effective approach for enhancing bicyclist conspicuity at night.

Hearing Impairment Affects Older People's Ability to Drive in the Presence of Distracters

OBJECTIVES: To investigate the effects of hearing impairment and distractibility on older peoples driving ability, assessed under real‐world conditions.

The prevention of childhood anxiety and promotion of resilience among preschool-aged children: a universal school based trial

This study is the first to examine the effectiveness of the Fun FRIENDS programme, a school-based, universal preventive intervention for early childhood anxiety and promotion of resilience delivered by classroom teachers. Participants (N = 488) included children aged 4–7 years attending 1 of 14 Catholic Education schools in Brisbane, Australia. The schools were randomly allocated to one of three groups, the intervention, active comparison and waitlist control group. Parents completed standardized measures of anxiety and behavioural inhibition (BI), resilience, social and emotional functioning and behaviour difficulties in addition to parental stress and anxiety, at pre- and post- and 12-month follow-up. Teachers also completed a parallel measure of social and emotional strength at the three time points. Comparable results were obtained for the intervention and comparison groups; however, the intervention group (IG) achieved greater reductions in BI, child behavioural difficulties and improvements in social and emotional competence. In addition, significant improvements in parenting distress and parent–child interactions were found for the IG, with gains maintained at 12-month follow-up. Teacher reports revealed more significant improvement in social and emotional competence for the IG. Clinical implications of the findings are discussed, along with limitations and directions for future research.

Simulated Visual Impairment Leads to Cognitive Slowing in Older Adults

Purpose. To investigate the impact of different levels of simulated visual impairment on the cognitive test performance of older adults and to compare this with previous findings in younger adults. Methods. Cognitive performance was assessed in 30 visually normal, community-dwelling older adults (mean = 70.2 ± 3.9 years). Four standard cognitive tests were used including the Digit Symbol Substitution Test, Trail Making Tests A and B, and the Stroop Color Word Test under three visual conditions: normal baseline vision and two levels of cataract simulating filters (Vistech), which were administered in a random order. Distance high-contrast visual acuity and Pelli-Robson letter contrast sensitivity were also assessed for all three visual conditions. Results. Simulated cataract significantly impaired performance across all cognitive test performance measures. In addition, the impact of simulated cataract was significantly greater in this older cohort than in a younger cohort previously investigated. Individual differences in contrast sensitivity better predicted cognitive test performance than did visual acuity. Conclusions. Visual impairment can lead to slowing of cognitive performance in older adults; these effects are greater than those observed in younger participants. This has important implications for neuropsychological testing of older populations who have a high prevalence of cataract.

Using biological motion to enhance the conspicuity of roadway workers

This study examined whether the conspicuity of road workers at night can be enhanced by distributing retroreflective strips across the body to present a pattern of biological motion (biomotion). Twenty visually normal drivers (mean age = 40.3 years) participated in an experiment conducted at two open-road work sites (one suburban and one freeway) at night-time. At each site, four road workers walked in place wearing a standard road worker night vest either (a) alone, (b) with additional retroreflective strips on thighs, (c) with additional retroreflective strips on ankles and knees, or (d) with additional retroreflective strips on eight moveable joints (full biomotion). Participants, seated in stationary vehicles at three different distances (80 m, 160 m, 240 m), rated the relative conspicuity of the four road workers. Road worker conspicuity was maximized by the full biomotion configuration at all distances and at both sites. The addition of ankle and knee markings also provided significant benefits relative to the standard vest alone. The effects of clothing configuration were more evident at the freeway site and at shorter distances. Overall, the full biomotion configuration was ranked to be most conspicuous and the vest least conspicuous. These data provide the first evidence that biomotion effectively enhances conspicuity of road workers at open-road work sites.