Ethnic differences in health in Scotland : the contrast between morbidity and mortality

In Scotland, most minority ethnic groups live longer than the White Scottish population but whether they report better health is unclear. Similarly, the international literature on ethnicity and health is divided between a strand that highlights the overall morbidity disadvantage in ethnic minorities and another strand that is puzzled by their mortality advantage. This thesis brings the two strands together by investigating whether ethnic patterns in morbidity and mortality align, based on a unique population source. The Scottish Health and Ethnicity Linkage Study links the Scottish Census 2001 to 12 years of hospitalisation and death records and provides a considerable sample size (4.6 million people) for this research. Therefore, this thesis makes a number of methodological contributions in addition to providing key empirical evidence of an ethnic morbidity-mortality paradox in Scotland. In particular, healthy life expectancy by sex and ethnicity is calculated for the first time in the UK using a direct method. Findings highlight the shortest healthy life expectancies in the Pakistani population contrasting with their mortality advantage. Hence, the Pakistani population experiences the highest number of years in poor health in Scotland. Indeed, the Pakistani population reports poorer health than the majority population which contrasts with their mortality advantage. This contrast persists beyond socio-economic circumstances and across migrant generations. Furthermore, using interaction analyses, this research demonstrates that reporting poorer health strongly predicts higher risks of mortality in minority ethnic groups but with greater strength for particular groups. Finally, findings show higher risks of (hospitalisation-based) multimorbidity in the Pakistani population which supports their morbidity disadvantage in Scotland. Diseases underlying this disadvantage include those related to the metabolic syndrome and respiratory disease. Policy makers should aim to improve the quality of life of the Pakistani population of Scotland while future research pinpoints the root causes of this morbidity-mortality paradox

Evidencing the gap between health expectancy and life expectancy for ethnic groups in Scotland

Background Recent evidence has shown that ethnic minorities live longer than the majority population in Scotland. This mortality advantage in ethnic minorities is not unique to Scotland. However, whether morbidity patterns by ethnicity align with mortality patterns by ethnicity is unknown. Thus, this study explores ethnic differences in health expectancies (HE) in Scotland and contrasts HE with life expectancy (LE) findings. Methods The Scottish Health and Ethnicity Linkage study anonymously links the Scottish Census 2001 for 4.6 million people to mortality records. The Scottish Census 2001 collected two measures of self-assessed health, self-declared ethnicity, age, and sex. Utilising the life tables used to calculate life expectancy by ethnicity and sex in Scotland, the Sullivan method was employed to calculate two measures of health expectancy (healthy life expectancy and disability-free life expectancy) by ethnicity and sex. 95% confidence intervals were calculated to detect significant differences compared to the majority White Scottish population, taken as reference. Results Longer health expectancies were found in males and females of Other White British, Other White, and Chinese origins as well as in Indian males compared to White Scottish populations. Any Mixed Background and Pakistani populations had the shortest healthy life expectancies. Patterns of health expectancy by ethnicity mostly aligned with patterns of life expectancy by ethnicity with the clear exception of the Pakistani population who showed among the longest life expectancies with the shortest health expectancies. Contrasting HE with LE findings, the number of years in an unhealthy state was greater in females than in males for each ethnic group. In relation to ethnicity, Pakistani and Indian populations had the highest number of years in an unhealthy state in Scotland. Pakistani females showed the strong-est disadvantage in this respect. Conclusion Pakistani populations had the shortest health expectancies contrasting with the longest life expectancies in Scotland. Future research should aim to understand why such a discrepancy occurs while policy makers ensure that fair and adapt-ed care is provided to offer better quality of life for the most vulnerable.Publisher PDFPeer reviewe

Impact of experimental conditions on material response during forming of steel in semi-solid state

Semi-solid forming is an effective near-net-shape forming process to produce components with complex geometry and in fewer forming steps. It benefits from the complex thixotropic behaviour of semi-solids. However, the consequences of such behaviour on the flow during thixoforming, is still neither completely characterized and nor fully understood, especially for high melting point alloys. The study described in this paper investigates thixoextrusion for C38 low carbon steel material using dies at temperatures much lower than the slug temperature. Four different process parameters were studied: the initial slug temperature, the die temperature, the ram speed and the presence of a ceramic layer at the tool/material interface. The extruded parts were found to have an exact shape and a good surface state only if the temperature was below a certain value. This critical temperature is not an intrinsic material property since its value depends on die temperature and the presence of the Ceraspray©layer. Two kinds of flow were highlighted: a homogeneous flow controlled by the behaviour of the solid skeleton characterized by a positive strain rate sensitivity, and a non homogeneous flow (macro liquid/solid phase separation) dominated by the flow of the free liquid. With decreasing ram speed, heat losses increase so that the overall consistency of the material improves, leading to apparent negative strain rate sensitivity. Finally, some ways to optimise thixoforming are proposed

Special features of RAD Sequencing data:implications for genotyping

Restriction site-associated DNA Sequencing (RAD-Seq) is an economical and efficient method for SNP discovery and genotyping. As with other sequencing-by-synthesis methods, RAD-Seq produces stochastic count data and requires sensitive analysis to develop or genotype markers accurately. We show that there are several sources of bias specific to RAD-Seq that are not explicitly addressed by current genotyping tools, namely restriction fragment bias, restriction site heterozygosity and PCR GC content bias. We explore the performance of existing analysis tools given these biases and discuss approaches to limiting or handling biases in RAD-Seq data. While these biases need to be taken seriously, we believe RAD loci affected by them can be excluded or processed with relative ease in most cases and that most RAD loci will be accurately genotyped by existing tools

Prediction of user intentions when operating with the cursor

Studies have shown that when we operate the cursor on a computer, several factors such as the type of device used (i.e. mouse or touchpad), aging (young vs. old) or motor-impairment can hinder performances. More precisely, using the touchpad can be difficult for any user, even for the most basic tasks, due to the absence of scrolling wheel and the reduced amplitude of cursor movement. To cope with these issues, I developed a set of tools to increase the usability of the touchpad by analyzing mouse-tracking data. More specifically, several movement patterns or cues were predefined and when they were detected, they would trigger the auto-completion of the related task which includes navigating on a web browser, selecting text and scrolling. The usability experiment conducted to assess the ease-of-use of the created tools and to compare the performances of participants showed promising results. Participants appreciated the help of the auto-completion tools and when they were able to trigger these tools, they were significantly faster. In particular, when moving the cursor to the URL address bar they even outperformed Fitts’ law predictions. However, it appeared that participants needed several attempts to draw certain cues correctly hence a longer completion time

Younger but sicker? : Cohort trends in disease accumulation among middle-aged and older adults in Scotland using health-linked data from the Scottish Longitudinal Study

This research was supported by the Economic and Social Research Council (ESRC) Centre for Population Change Connecting Generations research programme, grant number ES/W002116/1. This work was supported by the Academy of Medical Sciences, the Wellcome Trust, the Government Department of Business, Energy and Industrial Strategy, the British Heart Foundation Diabetes UK, and the Global Challenges Research Fund [Grant number SBF004\1093 awarded to Katherine Keenan]. The contribution from AM is funded by the National Institute for Health and Care Research (grant number NIHR202639).Background In the United Kingdom, rising prevalence of multimorbidity—the co-occurrence of two or more chronic conditions- is coinciding with stagnation in life expectancy. We investigate patterns of disease accumulation and how they vary by birth cohort, social and environmental inequalities in Scotland, a country which has long suffered from excess mortality and poorer health outcomes relative to its neighbours. Methods Using a dataset which links census data from 1991, 2001 and 2011 to disease registers and hospitalization data, we follow cohorts of adults aged 30–69 years for 18 years. We model physical and mental disease accumulation using linear mixed-effects models. Results Recent cohorts experience higher levels of chronic disease accumulation compared to their predecessors at the same ages. Moreover, in more recently born cohorts we observe socioeconomic status disparities emerging earlier in the life course, which widen over time and with every successive cohort. Patterns of chronic conditions are also changing, and the most common diseases suffered by later born cohorts are cancer, hypertension, asthma, drug and alcohol problems and depression. Conclusion We recommend policies which target prevention of chronic disease in working age adults, considering how and why certain conditions are becoming more prevalent across time and space.Peer reviewe

Determinants of services expectations : an application to the airline industry

Understanding consumer expectations is a key to deliver superior services. The role of expectations has received attention in both satisfaction and perceived quality literature domains but no agreement has been reached concerning the nature and formation of expectations. The present study reviewed the antecedents of consumer expectations discussed in the literature and incorporated some of them into a model. Then it looked at the impact of individualism/collectivism on the formation of expectations. Regressions were conducted to see which antecedents influenced expectations. Two different types of expectations were found and results revealed that many antecedents related to external and internal sources of information, values, number of perceived alternatives and other personal characteristics influence one or the two types of expectations. Interesting theoretical and managerial implications were found concerning the proposed model. The study also revealed that differences exist between individualists and collectivists with regard to the formation of expectations; however, the differences were not as expected

The 10-year follow-up of a community-based cohort of people with diabetes : the incidence of foot ulceration and death

Funding: This work was funded as part of a wider project by the National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme (HTA project: 15/171/01).Background: Identifying people with diabetes who are likely to experience a foot ulcer is an important part of preventative care. Many cohort studies report predictive models for foot ulcerations and for people with diabetes, but reports of long-term outcomes are scarce. Aim: We aimed to develop a predictive model for foot ulceration in diabetes using a range of potential risk factors with a follow-up of 10 years after recruitment. A new foot ulceration was the outcome of interest and death was the secondary outcome of interest. Design: A 10-year follow-up cohort study. Methods:  1193 people with a diagnosis of diabetes who took part in a study in 2006–2007 were invited to participate in a 10-year follow-up. We developed a prognostic model for the incidence of incident foot ulcerations using a survival analysis, Cox proportional hazards model. We also utilised survival analysis Kaplan–Meier curves, and relevant tests, to assess the association between the predictor variables for foot ulceration and death. Results: At 10-year follow-up, 41% of the original study population had died and more than 18% had developed a foot ulcer. The predictive factors for foot ulceration were an inability to feel a 10 g monofilament or vibration from a tuning fork, previous foot ulceration and duration of diabetes.  Conclusions: The prognostic model shows an increased risk of ulceration for those with previous history of foot ulcerations, insensitivity to a 10 g monofilament, a tuning fork and duration of diabetes. The incidence of foot ulceration at 10-year follow-up was 18%; however, the risk of death for this community-based population was far greater than the risk of foot ulceration.Publisher PDFPeer reviewe

Younger but sicker?:Cohort trends in disease accumulation among middle-aged and older adults in Scotland using health-linked data from the Scottish Longitudinal Study

BackgroundIn the United Kingdom, rising prevalence of multimorbidity—the co-occurrence of two or more chronic conditions- is coinciding with stagnation in life expectancy. We investigate patterns of disease accumulation and how they vary by birth cohort, social and environmental inequalities in Scotland, a country which has long suffered from excess mortality and poorer health outcomes relative to its neighbours.MethodsUsing a dataset which links census data from 1991, 2001 and 2011 to disease registers and hospitalization data, we follow cohorts of adults aged 30–69 years for 18 years. We model physical and mental disease accumulation using linear mixed-effects models.ResultsRecent cohorts experience higher levels of chronic disease accumulation compared to their predecessors at the same ages. Moreover, in more recently born cohorts we observe socioeconomic status disparities emerging earlier in the life course, which widen over time and with every successive cohort. Patterns of chronic conditions are also changing, and the most common diseases suffered by later born cohorts are cancer, hypertension, asthma, drug and alcohol problems and depression.ConclusionWe recommend policies which target prevention of chronic disease in working age adults, considering how and why certain conditions are becoming more prevalent across time and space

Influence de la vitesse de mise en forme et du cycle de chauffe sur le thixoforgeage des aciers

Analyse l’influence de la vitesse du coulisseau et de la température du lopin (fraction liquide) sur le comportement de l’acier à l’état semi-solide en utilisant un nouvel outillage de filage direct monté sur une presse hydraulique. Cette nouvelle conception évite la décélération du vérin rapide pendant la mise en forme. Il permet donc des essais à vitesse constante. Ce travail s’intéresse également à l’écoulement de la matière dans le cas du thixoforgeage de l’acier et montre l’importance d’un couplage entre la température initiale et la vitesse de déformation. Les différentes conditions permettant d’avoir un écoulement homogène et continu, avec un effort de mise en forme faible, sont étudiées et présentées.This paper analyses the influence of two parameters (tool axis speed and billet temperature) on semi-solid steel alloy behaviour. A new design of direct filling tool is proposed and adapted on hydraulic press. This concept avoids the speed decrease during forming process. This works shows thermal exchange influence in thixoforging process in function speed raw and initial temperature inside the billet by analysis forming loads and part geometries