Study of Optimal Perimetric Testing In Children (OPTIC): Normative visual field values in children

Purpose: We sought to define normative visual field (VF) values for children using common clinical test protocols for kinetic and static perimetry. Design: Prospective, observational study. Subjects: We recruited 154 children aged 5 to 15 years without any ophthalmic condition that would affect the VF (controls) from pediatric clinics at Moorfields Eye Hospital. Methods: Children performed perimetric assessments in a randomized order using Goldmann and Octopus kinetic perimetry, and Humphrey static perimetry (Swedish Interactive Thresholding Algorithm [SITA] 24-2 FAST), in a single sitting, using standardized clinical protocols, with assessment by a single examiner. Unreliable results (assessed qualitatively) were excluded from the normative data analysis. Linear, piecewise, and quantile mixed-effects regression models were used. We developed a method to display age-specific normative isopters graphically on a VF plot to aid interpretation. Main Outcome Measures: Summary measures and graphical plots describing normative VF data for 3 common perimetric tests. Results: Visual field area increased with age on testing with Goldmann isopters III4e, I4e, and I2e (linear regression; P < 0.001) and for Octopus isopters III4e and I4e (linear regression; P < 0.005). Visual field development occurs predominately in the infero-temporal field. Humphrey mean deviation (MD) showed an increase of 0.3 decibels (dB; 95% CI, 0.21-0.40) MD per year up to 12 years of age, when adult MD values were reached and thereafter maintained. Conclusions: Visual field size and sensitivity increase with age in patterns that are specific to the perimetric approach used. These developmental changes should be accounted for when interpreting perimetric test results in children, particularly when monitoring change over time

Solving Tree Problems with Category Theory

Artificial Intelligence (AI) has long pursued models, theories, and techniques to imbue machines with human-like general intelligence. Yet even the currently predominant data-driven approaches in AI seem to be lacking humans' unique ability to solve wide ranges of problems. This situation begs the question of the existence of principles that underlie general problem-solving capabilities. We approach this question through the mathematical formulation of analogies across different problems and solutions. We focus in particular on problems that could be represented as tree-like structures. Most importantly, we adopt a category-theoretic approach in formalising tree problems as categories, and in proving the existence of equivalences across apparently unrelated problem domains. We prove the existence of a functor between the category of tree problems and the category of solutions. We also provide a weaker version of the functor by quantifying equivalences of problem categories using a metric on tree problems.Comment: 10 pages, 4 figures, International Conference on Artificial General Intelligence (AGI) 201

Study of Optimal Perimetric Testing In Children (OPTIC): Development and feasibility of the kinetic perimetry reliability measure (KPRM)

INTRODUCTION: Interpretation of perimetric findings, particularly in children, relies on accurate assessment of test reliability, yet no objective measures of reliability exist for kinetic perimetry. We developed the kinetic perimetry reliability measure (KPRM), a quantitative measure of perimetric test reproducibility/reliability and report here its feasibility and association with subjective assessment of reliability. METHODS: Children aged 5-15 years, without an ophthalmic condition that affects the visual field, were recruited from Moorfields Eye Hospital and underwent Goldmann perimetry as part of a wider research programme on perimetry in children. Subjects were tested with two isopters and the blind spot was plotted, followed by a KPRM. Test reliability was also scored qualitatively using our examiner-based assessment of reliability (EBAR) scoring system, which standardises the conventional clinical approach to assessing test quality. The relationship between KPRM and EBAR was examined to explore the use of KPRM in assessing reliability of kinetic fields. RESULTS: A total of 103 children (median age 8.9 years; IQR: 7.1 to 11.8 years) underwent Goldmann perimetry with KPRM and EBAR scoring. A KPRM was achieved by all children. KPRM values increased with reducing test quality (Kruskal-Wallis, p=0.005), indicating greater testretest variability, and reduced with age (linear regression, p=0.015). One of 103 children (0.97%) demonstrated discordance between EBAR and KPRM. CONCLUSION: KPRM and EBAR are distinct but complementary approaches. Though scores show excellent agreement, KPRM is able to quantify withintest variability, providing data not captured by subjective assessment. Thus, we suggest combining KPRM with EBAR to aid interpretation of kinetic perimetry test reliability in children

Study of Optimal Perimetric Testing in Children (OPTIC): evaluation of kinetic approaches in childhood neuro-ophthalmic disease

AIMS: We compared feasibility, quality and outcomes of visual field (VF) testing in children with neuro-ophthalmic disease between the discontinued 'gold-standard' Goldmann and Octopus perimeters. METHODS: Children with neuro-ophthalmic disease, attending Great Ormond Street Hospital, London, were assessed using standardised protocols by one examiner in a single sitting, using Goldmann and Octopus kinetic perimetry. Outputs were classified to compare severity of loss and defect type. Test quality was assessed using both qualitative and quantitative methods. RESULTS: Thirty children (40% female) aged 5-15 years participated. Goldmann perimetry was completed in full by 90.0% vs 72.4% for Octopus. Inability to plot the blind spot was the most common reason for not completing testing. Over 75% completed a test in ≤20 min. Duration was similar between perimeters (paired t-test, mean difference: 0.48min (-1.2, 2.2), p=0.559). The lowest quality tests were for Octopus perimetry in children <8 years, without significant differences between perimeters in older children (McNemar's test, χ2=1.0, p=0.317). There was broad agreement between Goldmann and Octopus outputs (good quality, n=21, Bland-Altman, mean difference for isopters I4e (-514.3  deg2 (-817.4, -211.2), p=0.814), I2e (-575.5 deg2 (-900.1, -250.9), p=0.450) and blind spot (20.8 deg2 (5.7, 35.8), p=0.451)). However, VF severity grades and defect type matched in only 57% and 69% of tests, respectively. Octopus perimetry underestimated severe VF defects. CONCLUSIONS: Informative perimetry is feasible in children ≥8 years with neuro-ophthalmic conditions, with either Goldmann or Octopus perimeters. However, meaningful differences exist between the two approaches with implications for consistency in longitudinal assessments

Study of Optimal Perimetric Testing In Children (OPTIC): developing consensus and setting research priorities for perimetry in the management of children with glaucoma

BACKGROUND: Perimetry is important in the management of children with glaucoma, but there is limited evidence-based guidance on its use. We report an expert consensus-based study to update guidance and identify areas requiring further research. METHODS: Experts were invited to participate in a modified Delphi consensus process. Panel selection was based on clinical experience of managing children with glaucoma and UK-based training to minimise diversity of view due to healthcare setting. Questionnaires were delivered electronically, and analysed to establish 'agreement'. Divergence of opinions was investigated and resolved where possible through further iterations. RESULTS: 7/9 experts invited agreed to participate. Consensus (≥5/7 (71%) in agreement) was achieved for 21/26 (80.8%) items in 2 rounds, generating recommendations to start perimetry from approximately 7 years of age (IQR: 6.75-7.25), and use qualitative methods in conjunction with automated reliability indices to assess test quality. There was a lack of agreement about defining progressive visual field (VF) loss and methods for implementing perimetry longitudinally. Panel members highlighted the importance of informing decisions based upon individual circumstances-from gauging maturity/capability when selecting tests and interpreting outcomes, to accounting for specific clinical features (e.g. poor IOP control and/or suspected progressive VF loss) when making decisions about frequency of testing. CONCLUSIONS: There is commonality of expert views in relation to implementing perimetry and interpreting test quality in the management of children with glaucoma. However, there remains a lack of agreement about defining progressive VF loss, and utilising perimetry over an individuals' lifetime, highlighting the need for further research

Service use of older people who participate in primary care health promotion: a latent class analysis

Background: Recruiting patients to health promotion programmes who will benefit is crucial to success. A key policy driver for health promotion in older people is to reduce health and social care use. Our aim was to describe service use among older people taking part in the Multi-dimensional Risk Appraisal for Older people primary care health promotion programme. Methods: A random sample of 1 in 3 older people (≥65 years old) was invited to participate in the Multi-dimensional Risk Appraisal for Older people project across five general practices in London and Hertfordshire. Data collected included socio-demographic characteristics, well-being and functional ability, lifestyle factors and service use. Latent class analysis (LCA) was used to identify groups based on use of the following: secondary health care, primary health care, community health care, paid care, unpaid care, leisure and local authority resources. Differences in group characteristics were assessed using univariate logistic regression, weighted by probability of class assignation and clustered by GP practice. Results: Response rate was 34% (526/1550) with 447 participants presenting sufficient data for analysis. LCA using three groups gave the most meaningful interpretation and best model fit. About a third (active well) were fit and active with low service use. Just under a third (high NHS users) had high impairments with high primary, secondary and community health care contact, but low non-health services use. Just over a third (community service users) with high impairments used community health and other services without much hospital use. Conclusion: Older people taking part in the Multi-dimensional Risk Appraisal for Older people primary care health promotion can be described as three groups: active well, high NHS users, and community service users

Predicting dementia from primary care records: a systematic review and meta-analysis

Introduction Possible dementia is usually identified in primary care by general practitioners (GPs) who refer to specialists for diagnosis. Only two-thirds of dementia cases are currently recorded in primary care, so increasing the proportion of cases diagnosed is a strategic priority for the UK and internationally. Clinical entities in the primary care record may indicate risk of developing dementia, and could be combined in a predictive model to help find patients who are missing a diagnosis. We conducted a meta-analysis to identify clinical entities with potential for use in such a predictive model for dementia in primary care. Methods and Findings We conducted a systematic search in PubMed, Web of Science and primary care database bibliographies. We included cohort or case-control studies which used routinely collected primary care data, to measure the association between any clinical entity and dementia. Meta-analyses were performed to pool odds ratios. A sensitivity analysis assessed the impact of non-independence of cases between studies. From a sift of 3836 papers, 20 studies, all European, were eligible for inclusion, comprising >1 million patients. 75 clinical entities were assessed as risk factors for all cause dementia, Alzheimer’s (AD) and Vascular dementia (VaD). Data included were unexpectedly heterogeneous, and assumptions were made about definitions of clinical entities and timing as these were not all well described. Meta-analysis showed that neuropsychiatric symptoms including depression, anxiety, and seizures, cognitive symptoms, and history of stroke, were positively associated with dementia. Cardiovascular risk factors such as hypertension, heart disease, dyslipidaemia and diabetes were positively associated with VaD and negatively with AD. Sensitivity analyses showed similar results. Conclusions These findings are of potential value in guiding feature selection for a risk prediction tool for dementia in primary care. Limitations include findings being UK-focussed. Further predictive entities ascertainable from primary care data, such as changes in consulting patterns, were absent from the literature and should be explored in future studies

Predictors of Intraspinal Pressure and Optimal Cord Perfusion Pressure After Traumatic Spinal Cord Injury.

BACKGROUND/OBJECTIVES: We recently developed techniques to monitor intraspinal pressure (ISP) and spinal cord perfusion pressure (SCPP) from the injury site to compute the optimum SCPP (SCPPopt) in patients with acute traumatic spinal cord injury (TSCI). We hypothesized that ISP and SCPPopt can be predicted using clinical factors instead of ISP monitoring. METHODS: Sixty-four TSCI patients, grades A-C (American spinal injuries association Impairment Scale, AIS), were analyzed. For 24 h after surgery, we monitored ISP and SCPP and computed SCPPopt (SCPP that optimizes pressure reactivity). We studied how well 28 factors correlate with mean ISP or SCPPopt including 7 patient-related, 3 injury-related, 6 management-related, and 12 preoperative MRI-related factors. RESULTS: All patients underwent surgery to restore normal spinal alignment within 72 h of injury. Fifty-one percentage had U-shaped sPRx versus SCPP curves, thus allowing SCPPopt to be computed. Thirteen percentage, all AIS grade A or B, had no U-shaped sPRx versus SCPP curves. Thirty-six percentage (22/64) had U-shaped sPRx versus SCPP curves, but the SCPP did not reach the minimum of the curve, and thus, an exact SCPPopt could not be calculated. In total 5/28 factors were associated with lower ISP: older age, excess alcohol consumption, nonconus medullaris injury, expansion duroplasty, and less intraoperative bleeding. In a multivariate logistic regression model, these 5 factors predicted ISP as normal or high with 73% accuracy. Only 2/28 factors correlated with lower SCPPopt: higher mean ISP and conus medullaris injury. In an ordinal multivariate logistic regression model, these 2 factors predicted SCPPopt as low, medium-low, medium-high, or high with only 42% accuracy. No MRI factors correlated with ISP or SCPPopt. CONCLUSIONS: Elevated ISP can be predicted by clinical factors. Modifiable factors that may lower ISP are: reducing surgical bleeding and performing expansion duroplasty. No factors accurately predict SCPPopt; thus, invasive monitoring remains the only way to estimate SCPPopt

What factors in rural and remote extended clinical placements may contribute to preparedness for practice, from the perspective of students and clinicians?

What factors in rural and remote extended clinical placements may contribute to preparedness for practice, from the perspective of students and clinicians? Michele Daly, David Perkins, Koshila Kumar, Chris Roberts and Malcolm Moore Background: Community based rural education opportunities have expanded in Australia, attracting more medical students to placements in rural and remote settings. Aim: To identify the factors in an integrated, community engaged rural placement that may contribute to preparedness for practice (P4P), from the perspective of students and clinicians Methods: Forty two semi-structured interviews with medical students, supervisors and clinicians analysed thematically. Results: Opportunities for clinical learning, personal and professional development and cultural awareness were reported by students and clinicians as key factors that contribute to preparedness for practice. Potential barriers in rural and remote settings included geographical and academic isolation, perceived educational risk and differing degrees of program engagement. Conclusions: A longitudinal clinical placement in a rural setting may enable development of enhanced competencies leading to P4P. A rural setting can help provide a unique experience through hands-on learning, enhanced personal and professional development opportunities and observation of the cultural and contextual impact on health

Recommendations for the analysis of individually randomised controlled trials with clustering in one arm - a case of continuous outcomes

BACKGROUND: In an individually randomised controlled trial where the treatment is delivered by a health professional it seems likely that the effectiveness of the treatment, independent of any treatment effect, could depend on the skill, training or even enthusiasm of the health professional delivering it. This may then lead to a potential clustering of the outcomes for patients treated by the same health professional, but similar clustering may not occur in the control arm. Using four case studies, we aim to provide practical guidance and recommendations for the analysis of trials with some element of clustering in one arm. METHODS: Five approaches to the analysis of outcomes from an individually randomised controlled trial with clustering in one arm are identified in the literature. Some of these methods are applied to four case studies of completed randomised controlled trials with clustering in one arm with sample sizes ranging from 56 to 539. Results are obtained using the statistical packages R and Stata and summarised using a forest plot. RESULTS: The intra-cluster correlation coefficient (ICC) for each of the case studies was small (<0.05) indicating little dependence on the outcomes related to cluster allocations. All models fitted produced similar results, including the simplest approach of ignoring clustering for the case studies considered. CONCLUSIONS: A partially clustered approach, modelling the clustering in just one arm, most accurately represents the trial design and provides valid results. Modelling homogeneous variances between the clustered and unclustered arm is adequate in scenarios similar to the case studies considered. We recommend treating each participant in the unclustered arm as a single cluster. This approach is simple to implement in R and Stata and is recommended for the analysis of trials with clustering in one arm only. However, the case studies considered had small ICC values, limiting the generalisability of these results