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Population variation in handedness (a correlate of cerebral dominance for language) is in part genetic and, it has been suggested, its persistence represents a balanced polymorphism with respect to cognitive ability. This hypothesis was tested in a sample of 12,770 individuals in a UK national cohort (the National Child Development Study) by assessing relative hand skill (in a square checking task) as a predictor of verbal, non-verbal, and mathematical ability and reading comprehension at the age of 11 years. Whereas some modest decrements were present in extreme right handers the most substantial deficits in ability were seen close to the point of equal hand skill (“hemispheric indecision”). For verbal ability females performed better than males, but the relationship to relative hand skill was closely similar for the two sexes; for reading comprehension males close to the point of equal hand skill showed greater impairments than females. Analysed by writing hand the relationship of ability to hand skill appeared symmetrical about the point of “hemispheric indecision”. The variation associated with degrees of dominance may reflect the operation of continuing selection on the gene (postulated to be X-Y linked) by which language evolved and speciation occurred.

A response by S. J. Leask, D. J. Done and T. J. Crow to a letter to the editor that criticizes their article about the important relationship between the premorbid characteristics of individuals who later develop schizophrenic illnesses is presented.

A response by S.J. Leask and colleagues to a letter to the editor about their article "No association between breastfeeding and adult psychosis in two national birth cohorts" in volume 177 is presented.

Background and Aims: Current guidelines recommend 6 hours of solid food and 2 hours of clear liquid fasting for patients undergoing cardiac procedures with conscious sedation. There are no data to support this practice, and previous single centre studies support the safety of removing fasting requirements. The objective of this study was to determine the non-inferiority of a no fasting strategy to fasting prior to cardiac catheterisation procedures which require conscious sedation., Methods: This is a multicentre, investigator-initiated, non-inferiority randomised trial conduced in Australia with a prospective open label blinded endpoint design. Patients referred for coronary angiography, percutaneous coronary intervention or cardiac implantable electronic device (CIED) related procedures were enrolled. Patients were randomised 1:1 to fasting as normal (6 hours solid food and 2 hours clear liquid) or no fasting requirements (encouraged to have regular meals but not mandated to do so). Recruitment occurred from 2022 to 2023. The primary outcome was a composite of aspiration pneumonia, hypotension, hyperglycaemia and hypoglycaemia assessed with a Bayesian approach. Secondary outcomes included patient satisfaction score, new ventilation requirement (non-invasive and invasive), new intensive care unit admission, 30-day readmission, 30-day mortality, 30-day pneumonia., Results: 716 patients were randomised with 358 in each group. Those in the fasting arm had significantly longer solid food fasting (13.2 versus 3.0 hours, Bayes factor >100 indicating extreme evidence of difference) and clear liquid fasting times (7.0 versus 2.4 hours, Bayes factor >100). The primary composite outcome occurred in 19.1% of patients in the fasting arm and 12.0% of patients in the no fasting arm. The estimate of the mean posterior difference in proportions in the primary composite outcome was -5.2% (95% CI -9.6 to -0.9, ) favouring no fasting. This result confirms non-inferiority (posterior probability >99.5%) and superiority (posterior probability 99.1%) of no fasting for the primary composite outcome. The no fasting arm had improved patient satisfaction scores with a posterior mean difference of 4.02 points (95% CI 3.36 to 4.67, Bayes factor >100). Secondary outcome events were similar., Conclusions: In patients undergoing cardiac catheterisation and CIED related procedures, no fasting was non-inferior and superior to fasting for the primary composite outcome of aspiration pneumonia, hypotension, hyperglycaemia and hypoglycaemia. Patient satisfaction scores were significantly better with no fasting. This supports removing fasting requirements for patients undergoing cardiac catheterisation laboratory procedures that require conscious sedation., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

University students are recognized as a high-risk population group who experience greater rates of poor health outcomes and mental ill-health. Commencing university is recognized as a major life transition, where students experience new financial, academic, environmental, and social pressures that can cause changes in their normal behaviors. This study explored trends in health-risk behaviors and psychological distress in commencing university students over four survey years. First-year undergraduate students, aged 17-24, from an Australian university were included. A secondary analysis was performed on data collected via cross-sectional surveys on four occasions (2016, 2017, 2019, 2020). Crude logistic regression models were utilized to investigate the association between meeting guidelines and survey year. Odds ratios for the pairwise comparison between each year are reported. In this analysis, 1300 (2016), 484 (2017), 456 (2019), and 571 (2020) students were included. Analyses showed two clear trends: students' probability of being at high/very high risk of psychological distress (35-55%) and consuming breakfast daily (44-55%) consistently worsened over the four survey years. These findings suggest that the odds of psychological distress and daily breakfast consumption worsened over time, whilst the proportion of students engaging in some health-risk behaviors was high, highlighting the importance of early intervention during the transition to university.

Since 2010, New South Wales (NSW) Health has assisted local water utilities to develop and implement risk-based drinking water management systems based on the Australian Drinking Water Guidelines Framework for Management of Drinking Water Quality. This support has benefited regional communities, and especially smaller utilities, by helping to identify and control risks. NSW Health's support projects have resulted in statistically significant improvements across many elements of drinking water management system implementation. Through this program of support, NSW Health has identified possible infrastructure and operational needs and assessed implementation of drinking water management systems. In parallel, NSW Health has worked to assess the risk from Cryptosporidium in drinking water supplies and to develop a formal audit program. Findings from the NSW Health support program informed the development of two NSW Government programs and the commitment of more than $1 billion to help local water utilities address public health and other critical needs. The introduction of risk-based drinking water management systems has driven incremental improvement in drinking water quality management across the state of NSW.

Background: An inverse relationship between risk of schizophrenia and premorbid IQ is a robust empirical finding. Cognitive impairment may be a core feature of schizophrenia in addition to the clinical symptoms that have historically defined the disorder., Aims: To evaluate whether risk of schizophrenia increases linearly or nonlinearly with the lowering of premorbid IQ after adjustment for a range of confounding factors., Methods: IQ data from the 1958 National Child Development Study, a prospective national birth cohort (n = 17 419), were linked with psychiatric admissions in England and Wales over a 20-year period. Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnoses were derived from case notes., Results: A clear nonlinear inverse relationship between general intelligence at ages 7 and 11 and risk of adult psychosis was found even after adjustment for potential social, behavioral, or demographic confounding factors. No such relationship was found for affective disorders., Conclusions: The nonlinear relationship suggests an excess risk of schizophrenia in children with premorbid IQ in the learning disabilities range. Previous reports of a linear relationship are likely to be a result of less sensitive statistical methods for detecting nonlinearity.

It is widely believed that advantages of hemispheric asymmetries originated in better cognitive processing, hence it is often implied that the relationship between hemispheric asymmetry and cognitive performance is linearly positive: the higher the degree of lateralization in a specific cognitive domain, the better the performance in a corresponding task. Yet, the empirical evidence for this notion is mixed and the statistical methods to analyze this relationship have been criticized. The present study therefore investigated the relationship between hemispheric asymmetries and cognitive performance in two behavioral tasks (a left-lateralized word-matching task and a right-lateralized face-decision task) in 230 participants (140 women, 90 men) by using two different approaches. Both methods correspondingly revealed that a relationship between hemispheric asymmetries and cognitive performance does exist. Contrary to a positive (linear) relationship however, the data could be best described by an inverted U-shaped curve. Although the optimal degree of lateralization seemed to be task-specific, a slight or moderate degree of hemispheric asymmetry achieved best cognitive performance in all tasks. Moreover, performances deteriorated towards extreme ends of lateralization (i.e., participants with either extreme left or right hemispheric biases). Taken together, the present study provides evidence against the notion that higher lateralization is related to enhanced cognitive performance., (Copyright 2010 Elsevier Inc. All rights reserved.)

Aim: To determine factors associated with microbiological safety of public drinking water systems in regional New South Wales (NSW), Australia., Method: We analysed 107,000 end-user drinking water samples for an association between detection of Escherichia coli and drinking water system features, sample year and season using NSW Health Drinking Water Monitoring Program data, 2001-2007. We used negative binomial generalized estimating equations with adjustment for autocorrelation and clustering., Results: We detected E. coli in over 2% of samples from 40% (129/323) of systems. E. coli detection was significantly more common in earlier years and during summer (p<0.001). On multivariate analysis E. coli detection was significantly associated with smaller systems; watercourse sources; no disinfection or disinfection with ultraviolet only; and higher post-treatment mean turbidity (all p< or =0.01). Detection was most strongly associated with lack of disinfection (incidence rate ratio 12.6, p<0.001) and smaller supply systems (1% reduction in E. coli detection for each 1,000 person increase in supply population, p=0.004). Ultraviolet disinfection alone was the least effective disinfection method (p<0.001)., Conclusion: Even in developed countries, drinking water systems without disinfection or serving small populations appear vulnerable to the effects of faecal contamination, which presents a risk of waterborne disease outbreaks.

Introduction: Patients grouped by latent class analysis of symptoms show some consensus between studies, and may be less etiologically heterogeneous than current diagnoses. If so, the effect size of 'neurodevelopmental' risk factors may be greater than in equivalent DSMIV diagnostic groups., Method: Two hundred fifty six individuals with neurodevelopmental risk factors recorded in the National Child Development Study (1958) UK birth cohort were grouped by data-driven illness subtypes, derived previously in over 1000 individuals. The effect sizes of these risks were compared between data-derived and DSMIV schizophrenia (295.x) groups., Results: Compared to DSMIV schizophrenia, the data-driven subtype broadly characterized by the presence of psychotic symptoms in the absence of affective symptoms showed significantly greater effect sizes in eight out of thirteen continuously-rated risk factors: birth weight, cognition, childhood behavioural problems, and neurological softsigns including handedness., Conclusion: A data-driven subgroup of schizophrenia patients, characterized as lacking co-morbid depressive symptoms, is less heterogeneous with respect to neurodevelopmental etiology.

The heterogeneity of the schizophrenia phenotype is often considered an obstacle for genetic research. We therefore aim to identify subgroups of psychosis patients with a shared symptom profile by means of a fully data-driven analysis, which may serve as an alternative phenotype. We investigated the symptoms of 1056 patients that were referred to our hospital with a psychosis. The lifetime symptoms scores were derived from the current and lifetime ratings of the comprehensive assessment of psychiatric history (CASH) interview. We used latent class analysis (LCA) to identify clusters of patients with a shared symptom profile. The five indicators in our analysis were the total number of symptoms present for each of the five factors identified in a factor analysis of lifetime symptoms. We also analysed the discriminating power of these symptom dimensions in previous LCAs. A six-cluster division of psychotic phenotypes showed substantial overlap with earlier LCA analyses and findings from genetic association studies. The results included a bipolar and a depression subgroup in psychosis and showed that mood symptoms are the best discriminators of subgroups of psychosis. The distinction of subgroups of psychosis patients, in particular those with major mood symptoms could facilitate the unravelling of the genetics of psychotic disorders.

We examined the relationship between a history of obstetric complications (OCs) and the number of neurological soft signs (NSS) in a group of 132 patients experiencing their first episode of psychosis. We measured NSS by means of a comprehensive standardized assessment and gained information on a selection of nine OCs from the patient's mother. Contrary to our expectations we found significantly more NSS in the group of patients without a history of OCs. This effect was independent of medication in the group of patients with a schizophrenic disorder, but not in the entire group. It is possible that the patients with a history of OCs carry fewer genes for schizophrenia (and NSS) and 'needed' the OCs to develop schizophrenia.

We examined the 2-year stability of neurological soft signs (NSS) in 29 patients after a first episode of psychosis. The numbers of NSS at inclusion and at 2 years follow-up were similar, but there was a significant increase in the numbers of NSS in the sub-group of patients whose dosage of antipsychotic medication had increased over time.

The relationship between laterality and performance is unclear, and using laterality indices to explore this relationship can be misleading. An alternative approach is to consider laterality as a bivariate construct. A scatterplot of measures on each side will allow the distribution of values in a population to be visualised. However, determining where mean values lie in a population is problematic. Even nonparametric regression techniques such as lowess make assumptions about one variable being independent and the other dependent. Such assumptions are arbitrary in the case of measures by side. Assumptions of dependence are avoided using principal curve analysis. The results of two nonparametric fitting techniques (lowess regression and a principal curve analysis) are compared using hand skill data on 12,782 11-year-olds from a UK national birth cohort. The lowess regression is misleading. The principal curve analysis shows that absolute right-left performance differences increase with hand skill to a maximum about the point of average hand skill, and the difference is then constant up to extremes of hand skill.

The hypothesis that psychosis arises as a part of the genetic diversity associated with the evolution of language generates the prediction that illness will be linked to a gene determining cerebral asymmetry, which, from the evidence of sex chromosome aneuploidies, is present in homologous form on the X and Y chromosomes. We investigated evidence of linkage to markers on the X chromosome in 1) 178 families multiply affected with schizophrenia or schizoaffective disorder with a series of 16 markers spanning the centromere (study 1), and 2) 180 pairs of left-handed brothers with 14 markers spanning the whole chromosome (study 2). In study 1, excess allele-sharing was observed in brother-brother pairs (but not brother-sister or a small sample of sister-sister pairs) over a region of approximately 20 cM, with a maximum LOD score of 1.5 at DXS991. In study 2, an association between allele-sharing and degree of left-handedness was observed extending over approximately 60 cM, with a maximum lod score of 2.8 at DXS990 (approximately 20 cM from DXS991). Within the overlap of allele-sharing is located a block in Xq21 that transposed to the Y chromosome in recent hominid evolution and is now represented as two segments on Yp. In one of two XX males with psychosis we found that the breakpoint on the Y is located within the distal region of homology to the block in Xq21. These findings are consistent with the hypothesis that an X-Y homologous determinant of cerebral asymmetry carries the variation that contributes to the predisposition to psychotic illness.