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Abstract Background Falls are the second leading cause of accidental deaths worldwide mainly in older people. Older people have poor vision and published evidence suggests that it is a risk factor for falls. Less than half of falls clinics assess vision as part of the multi-factorial assessment of older adults at risk of falls despite vision being an essential input for postural stability. The aim of our study was to investigate the relationship between all clinically assessed visual functions and falls amongst older adults in a prospective observational individually age-matched case control study. Methods Visual acuity (VA), contrast sensitivity (CS), depth perception, binocular vision and binocular visual field were measured using routinely used clinical methods in falls participants (N = 83) and non-falls participants (N = 83). Data were also collected on socio-demographic factors, general health, number of medications, health quality, fear of falling and physical activity. Logistic regression analysis was carried out to determine key visual and non-visual risk factors for falls whilst adjusting for confounding covariates. Results Older adults have an increased risk of experiencing a fall if they have reduced visual function (odds ratio (OR): 3.49, 1.64-7.45, p = 0.001), specifically impaired stereoacuity worse than 85” of arc (OR: 3.4, 1.20-9.69, p = 0.02) and reduced (by 0.15 log unit) high spatial frequency CS (18 cpd) (OR:1.40, 1.12-1.80, p = 0.003). Older adults with a hearing impairment are also at higher risk of falls (OR: 3.18, 95% CI: 1.36-7.40, p = 0.007). The risk decreases with living in a less deprived area (OR: 0.74, 0.64-0.86,

Aims: To validate the design of updated optotypes to be used in the Kay picture acuity tests to improve the resolution acuity, recognition, repeatability and comparisons with gold standard logMAR acuity assessments. Methods: The study was completed in four phases. Inball phases the pictures were presented on a monitor as a single crowded optotype, with five optotypes at each visual acuity (VA) level. Phase one assessed the resolution acuity for 25 pictures, eight Landolt Csband five ETDRS letters. The recognition phase (phasebtwo) assessed children (18 months to 5 years) to determine which pictures were most commonly identified. During phase three, the resolution acuity of a reduced number of pictures and the Landolt C were reassessed to ensure that fatigue had not influenced the initial results. Phase four compared the new Kay pictures with LEA symbols and the ETDRS (part a), and repeatability of the Kay pictures and the ETDRS chart (part b). Results: 'Phase one (resolution acuity)': 50 adult subjects were tested. The mean (±SD) acuity scores achieved using each of the 25 pictures ranged from -0.123 ±0.124 to -0.308 ±0.105. The mean (±SD)bacuity for the eight Landolt C orientations was -0.059 ±0.120, and -0.128 ±0.101 for the ETDRS letters. Following this analysis, three pictures were removed. Phase two (Recognition): 420 children were assessed (54% male) using the remaining 22 pictures. Analysis resulted in the removal of 10 pictures based on the recognition levels. Phase three (resolution acuity): 43 adult subjects were tested with the remaining 12 pictures. The picture selection was reduced to six based on a combination of similar mean bias levels, recognition levels in all children and recognition levels in the youngest children. Phase four (a) (comparability): 113 adult subjects were tested. The mean bias indicated similar results between the tests. The limits of agreement for ETDRS versus Lea symbols were slightly wider than for ETDRS versus Kay pictures. Phase four (b) (repeatability): 100 adult subjects were tested. Paired 't'-test analysis demonstrated no significant difference between tests in either ETDRS ( p = 0.1) or Kay pictures ( p = 0.1). Mean bias for both tests was 0.01 logMAR with similar limits of agreement. Conclusion: The newly designed Kay picture optotypes have been shown to be reliably recognised by a paediatric population. In a six-picture test format the newly designed optotypes with single picture presentation and crowding bars have been shown to be a reliable and repeatable VA test in an adult population with good agreement with current gold standard VA assessment methods. Normative data in a paediatric population are now required.

Aim: To discuss the information contrast sensitivity (CS) testing can provide over visual acuity testing, and review the literature relating to CS deficits in children to determine whether there is an optimum test available. Methods: A literature search of databases available through the University of Liverpool library was performed. All searches related to the importance of CS in children, paediatric conditions affecting CS and current clinical tests available for the assessment of CS. Results: Many paediatric conditions exist where CS is defective, often despite ‘normal’ visual acuity (VA): for example, optic pathway gliomas, myopia and primary congenital glaucoma. The finding of a loss of CS has been found to be more prominent and disturbing to an individual than a loss of VA, emphasising the importance of CS assessments in children. Therefore, the clinical assessment of CS in children is valuable in terms of strategies to support the child and establishing the individual’s functional level of vision. Unfortunately, current paediatric clinical tests of CS have failed to demonstrate the same standards and repeatability and reliability as adult tests for the assessment of CS. Conclusions: The range of functional deficits that accompany paediatric ocular disease require more assessments for full evaluation of visual function than standard VA tests. However, reliable assessments for paediatric CS are limited. A new paediatric CS test may be of clinical value.

Aim: To evaluate in a pilot study the use of a touchscreen test in very low birth weight (VLBW) children to explore aspects of visuo-motor behaviour, measuring spatial localisation. Results in VLBW subjects will be compared with those in children born at term. It will be investigated whether any deficits found were related to parental reports of visual function difficulties. Methods: A range of visual functions were measured and IQ estimated using subtests from a standardised test. Using a touch-screen monitor to record pointing positions, in task 1 subjects pointed to sequences of visual targets as soon as they appeared and in task 2 they pointed after a memory delay. Results: Thirty-seven VLBW subjects and 32 control subjects were recruited. On task 1 there was no difference in the pointing error magnitude between the groups. Although the errors of the VLBW group were more variable, this was not statistically significant after exclusion of VLBW subjects with IQ