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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Diseño de un modelo de análisis de sostenibilidad de políticas públicas en salud

Salas Zapata, Walter Alfredo 17 July 2012 (has links)
Public health policies are often influenced by social-ecological interactions that affect the achievement of policy goals and may produce early interruptions of actions. Paradigms, frameworks and models most commonly used in policy analysis do not account for the complexity of this phenomenon. Because of its transdisciplinary character, Sustainability Science may provide an appropriate perspective for crafting new models that allow scientists to understand these complex and dynamic interactions, specifically, by integrating different types of knowledge that reveal the network of social-ecological relationships affecting the behavior of actors involved in policies. AIM. This research aims to define the elements making up a model for analyzing public health policies from a sustainability science perspective. METHODOLOGY. This is a research of three stages. Firstly, foundations on sustainability science, transferable to health policy analysis, were theoretically developed by a documentary review. Secondly, a theoretical model was designed by reviewing some conceptual bases of modeling. Finally, the model was applied in a real context in order to estimate its scope and practical implications. This stage was carried out by a case study research attempting to analyze the sustainability of a malaria control policy in El Bagre (Colombia). RESULTS. Stage 1. Foundations on sustainability science were structured in three axes: ontology, epistemology and methodology. In the ontological axis, a study object for sustainability science was defined. This is the `social-ecological resilience of systems¿ and is supported on an historical ontology. In the epistemological axis, this research found that epistemological frameworks based on complex systems theory (transdisciplinary epistemology, transactional e. and reflexive e.) are the most appropriate ones for understanding unsustainability problems. In the methodological axis, this research found that one of the most important features of sustainability science is the problem-solving perspective, or use-inspired science. This perspective means that researches contribute to the solution of real problems. Some characteristics favoring this perspective are transdisciplinarity, participation, social learning, co-production of knowledge, accounting for multiple scales, and uncertainty management. Stage 2. The type of model structured here was a theoretical one. The crafting of this model led to theoretically develop the concept of social-ecological resilience and to design a model made up of three components of analysis which are: the social-ecological dynamics related to the target problem of health policies, the public policy tending to solve it, and the adjustment between the health policy and the social-ecological dynamics. Stage 3. The use of the model in the analysis of the malaria control policy in El Bagre (Colombia) enabled the research team to describe each model component. In the social-ecological dynamics component, for instance, this research found that gold mining and armed conflict are strongly related to malaria. The health policy component reveals the system of actors, their positions, interests and rules of action that give shape to the malaria control policy. In the adjustment policy-dynamics component, the research permitted to understand the sufficiency of the policy to adaptively respond to social-ecological dynamics of malaria. This study revealed that this policy is barely sustainable. CONCLUSION. This model is appropriate in account for social-ecological interactions affecting health policies. Nevertheless, theoretical and methodological principles still require additional progress. / . En el análisis de políticas públicas en salud se han venido utilizando modelos, enfoques y paradigmas de análisis que no dan cuenta de la complejidad del funcionamiento de este tipo de políticas. Las políticas públicas en salud suelen estar influenciadas por un entorno de relaciones socioecológicas que afectan el cumplimiento de los propósitos de la política pública y, en ocasiones, producen su interrupción temprana. Se requieren modelos que den cuenta de tal complejidad y la ciencia de la sostenibilidad puede brindar una perspectiva apropiada. Su carácter transdisciplinar permite integrar diferentes formas de conocimiento para revelar la red de relaciones socioecológicas que pueden afectar la conducto de los actores responsables de materializar las políticas. OBJETIVO. Esta tesis tiene por objetivo establecer los elementos estructuradores de un modelo para el análisis de políticas públicas en salud a partir de algunos fundamentos de la ciencia de la sostenibilidad. METODOLOGÍA. La investigación se desarrolló en tres etapas. En la primera, mediante una revisión documental, se desarrollaron teóricamente unos fundamentos de la ciencia de la sostenibilidad que sean aplicables al análisis de políticas públicas en salud. En la segunda se revisaron algunas orientaciones conceptuales sobre modelización y se diseñó un modelo teórico; y finalmente, se llevó a cabo un estudio de caso de una política de control de malaria en la localidad de El bagre (Colombia) para aplicar el modelo y analizar su alcance en un contexto real de aplicación. RESULTADOS. Los fundamentos para la ciencia de la sostenibilidad se estructuraron en tres ejes: ontológico, epistemológico y el metodológico. En el eje ontológico se definió que el objeto de estudio de la ciencia de la sostenibilidad es la resiliencia socioecológica de los sistemas y éste a su vez se fundamenta en una ontología histórica. En el eje epistemológico se encontró que las corrientes epistemológicas basadas en la teoría de los sistemas complejos (Epistemología transdisicplinar, E. Transaccional, E. Reflexiva) son las mas apropiadas para entender los problemas de insostenibilidad. En el eje metodológico se encontró que la perspectiva de solución de problemas es un rasgo característico de la ciencia de la sostenibilidad y que algunos principios como la transdisciplianriedad, participación, aprendizaje social, co-producción de conocimiento, la consideración de múltiples escalas y el manejo de la incertidumbre favorecen las posibilidades de que las investigaciones contribuyan a mejorar procesos de toma de decisiones. Con respecto al dseño del modelo, éste implicó desarrollar teóricamente el concepto de resiliencia socioecológica de los sistemas y ello derivó en un modelo constituido por tres componentes de análisis que son: las dinámicas socioecológicas relacionadas con el problema de salud que la política pública pretender resolver, la política pública misma, y el ajuste entre la política pública y las dinámicas socioecológicas. Para estimar el alcance del modelo en contextos reales, éste fue aplicado en el análisis de la política de control de malaria del municipio de El Bagre (Colombia). Este estudio de caso permitió observar, por ejemplo, que en el componente de dinámicas socioecológicas, la minería y el conflicto armado están muy relacionadas con la malaria; en el componente de la política pública, se describieron los actores, sus posiciones, reglas de operación, e intereses que dan lugar a la política de control, y en el ajuste se analizó la suficiencia de la política pública para responder a tales dinámicas. El estudio de caso reveló que esta política pública en El bagre es escasamente sostenible. CONCLUSIÓN. El modelo es apropiado para dar cuenta de la interacciones socioecológicas que influyen en las políticas públicas. Sin embargo, los principios teóricos y metodológicos aun requieren mayores desarrollos.
2

Anàlisi dels factors incidents en l'evolució de l'accidentabilitat laboral en el territori de Lleida: (període 1975-1984)

Guimet Pereña, Jordi 20 December 1990 (has links)
La teoria clàssica de l'accident considera el seu origen com a producte de tres factors incidents: el factor humà, el factor tècnic i el factor (micro)mediambiental, tots tres configurant el marc de producció.La tesi se centra en l'anàlisi dels factors macroambientals de tipus tècnic, econòmic, social i laboral, difícilment observables des de la perspectiva interna d'una empresa, i la seva incidència sobre l'accidentabilitat laboral, tot analitzant-ne les variacions produïdes al llarg del temps sobre el fenòmen de l'accidentabilitat.La hipótesis que s'intenta demostrar en la tesi és que existeix una relació causa-efecte entre el "macroambient" del sistema productiu determinat per unes variables socieconòmiques determinables i l'accidentabilitat en els diferents sectors productius. Es fa l'anàlisi al llarg del període de 10 anys, període complex en quant als canvis tecnològics, econòmics i socials.Es fa també un anàlisi de l'accidentabilitat en el període i un anàlisi de les dades econòmiques principals i al seva evolució en l'esmentat període. S'apliquen mètodes de regressió lineal (variable dependent : el nombre d'accidents).Es conclou que l'evolució económica arrastra una sèrie de conseqüències tècniques, laborals i socials que son les que realment tenen influència certa en el fenòmen de l'accidentabilitat. Més que determinar un model matemàtic predictiu s'ha aconseguit un model explicatiu de la interrelació que se suposava en la hipótesis.
3

The role of pre-trial attitudes about forensic science evidence : developing and testing a forensic evidence evaluation bias scale

Smith, Lisa L. January 2011 (has links)
The unique decision making task entrusted to lay juries in adversarial legal systems has attracted the attention of legal psychologists for decades, but more recently technological advances in forensic science have highlighted the importance of understanding how jurors perceive this often ambiguous and complicated type of evidence. This thesis begins by investigating the forensic awareness of lay participants, and the ability of mock jurors to discriminate between varying probative values of forensic evidence. The findings suggest that the perception of weak forensic evidence is affected by contextual information, and there was wide disagreement among participants about the probative value of weak evidence. In an effort to explain the variance in perceived evidence strength, a measure of pre-trial attitudes about forensic science was developed (the Forensic Evidence Evaluation Bias Scale – FEEBS) and administered to 446 participants ranging from students, to jury eligible members of the public, to actual jury venire persons. The results of exploratory and confirmatory factor analyses identified two distinct clusters of attitudes measured by the FEEBS, which correspond conceptually to the hypothesised juror beliefs described in the CSI Effect literature. These attitudes were found to have a significant indirect effect on verdict preference, for trial vignettes describing murder, robbery, and sexual assault scenarios containing weak (or absent) forensic DNA evidence. The implications of these findings for voir dire hearings are discussed, with reference to the cognitive models of juror decision making and the CSI Effect literature.
4

The relationship between adult anthropometry morbidity and functional status : a longitudinal study among rural Ethiopians

Feyissa, Ferew Lemma January 2002 (has links)
No description available.
5

Spatial epidemiology and the integrated control of malaria and lymphatic filariasis in Africa

Slater, Hannah Claire January 2012 (has links)
Malaria and lymphatic filariasis (LF) cause the largest public health burden of all vector-borne diseases worldwide. Some 350-500 million clinical episodes and 1 million deaths each year are caused by malaria, of which approximately 60% and 80% respectively occur in Africa. More than 50 million people are also thought to be infected with lymphatic filariasis in 39 endemic countries in sub-Saharan Africa, with approximately 14.6 million individuals living in these endemic countries estimated to suffer from the two major filarial debilitating conditions, lymphodema or hydrocele. These two infections are co-endemic in large parts of Africa and are transmitted by the same vector, namely the Anopheles mosquito. The overall aim of the PhD was to develop a framework which could be used to evaluate the economic costs and benefits of different control strategies for reducing or eliminating the transmission of LF and malaria in Africa and, in particular, considering whether integrated control could offer a more effective approach for disease control. This problem was split into three key areas: 1) Mapping the geographic distribution of malaria and LF infection in Africa and identifying areas where the infections are co-endemic. Initially a maximum entropy modelling approach was used to identify areas at risk of LF based on environmental factors and population density. Then, a Bayesian spatial modelling approach was used to map the prevalence of malaria and LF in Africa, to estimate the number of people infected, and to identify areas of co-endemicity. 2) Developing a combined malaria-LF transmission model for humans and mosquitoes. This involved integrating a LF transmission model into a malaria transmission model. Interactions between the infections were captured using the model, specifically the increase in vector mortality as a result of LF larvae infection, and alterations in the host immune response as a result of co-infection. The model was used to investigate how the presence of one infection affected the prevalence of the other. 3) Finally, performing an economic evaluation of the economic costs and benefits of different control strategies, focusing on the potential for an integrated control approach. The economic benefits of the two primary control approaches (long lasting insecticidal nets for malaria and mass drug administration for LF) were modelled for a range of different scenarios using the co-infection model. The benefit of a control strategy was defined as the financial cost of the resulting reduction in treatment costs and work days lost due to infection and disease. The cost-benefit analysis was used to identify the optimal control strategy for different infection prevalence scenarios and the results were combined with the maps created in 1) to produce maps showing the optimal control strategy for different regions of Africa.
6

Models for measuring and predicting malaria vaccine efficacy

White, Michael January 2012 (has links)
In the past decade several candidate malaria vaccines have undergone clinical trials in artificial challenge studies and studies of natural infection under field conditions. GlaxoSmithKline’s RTS,S vaccine against Plasmodium falciparum infection has taken the lead, with Phase III trials in African children demonstrating 55.8% (97.5% CI, 51.3% - 59.8%) efficacy against clinical malaria and 34.8% (95% CI, 16.2% – 49.2%) efficacy against severe malaria. Mathematical models can contribute to multiple stages of malaria vaccine development, from measuring efficacy in clinical trials, understanding the relationship between naturally acquired and vaccine-induced immunity, identifying correlates of protection, and predicting the likely impact of vaccination programs in the field. When measuring vaccine efficacy in field trials under natural exposure to malaria, there are many factors which can bias estimates of efficacy. We demonstrate how heterogeneity in exposure can cause efficacy to be underestimated and heterogeneity in vaccine response can cause efficacy to be overestimated. Most infection-blocking vaccines rely on boosting some element of the pre-erythrocytic immune response, however the relationship between the naturally acquired pre-erythrocytic responses and protection from infection remains poorly understood. By analysing studies from a systematic of the published literature, I demonstrate that although many studies report a statistically significant relationship between cellular pre-erythrocytic immune responses and protection from infection, many studies do not have sufficient statistical power to evaluate the effects of the pre-erythrocytic immune response. Mathematical models are developed for investigating the relationship between pre-erythrocytic antibodies and protection from infection, and fitted to data from a longitudinal study of malaria infection in Kenyan adults. The relationship between antibodies to the antigens circumsporozoite protein (CSP) and thrombospondin-related adhesion protein (TRAP) and protection from infection is characterised using dose-response curves. Using data from an artificial challenge trial of the RTS,S malaria vaccine, I demonstrate that vaccine-induced protection from infection depends on both anti-CSP antibodies and CSP-specific T cells. I estimate that RTS,S causes a 97.7% (95% CI, 96.3% – 98/7%) reduction in the number of parasites entering the blood from the liver. The immune effector mechanisms determining the duration of vaccine-induced protection from infection are likely to be similar to those involved in naturally acquired immunity. Models of antibody kinetics were fitted to data from longitudinal studies of the antibody response to P. falciparum infection in Ghanaian and Gambian children, and the parameters determining the duration of antibody response are estimated. Upon licensure, a successful malaria vaccine is likely to be administered to young African children. A model of malaria transmission, extensively fitted to clinical data, is used to investigate the impact of vaccination in different transmission settings; the interaction between vaccines and other interventions such as insecticide treated nets; and the interaction between vaccination and naturally acquired immunity. Finally, the potential cost-effectiveness of vaccination is explored.
7

Methicillin-resistant Staphylococcus aureus : a novel approach to molecular detection and a US countywide study of strain diversity and distribution among healthcare facilities

Hudson, Lyndsey Olivia January 2012 (has links)
Methicillin-resistant Staphylococcus aureus (MRSA) is a global public health problem and is a major cause of morbidity and mortality worldwide, imposing serious economic costs on patients and hospitals. Prior to the mid-1990s, MRSA was largely a healthcare-associated pathogen, causing infection predominantly in people with frequent or recent contact with healthcare facilities (HA-MRSA). Since then, community-associated MRSA (CA-MRSA), which often causes infection among healthy children and young adults with no exposure to the healthcare setting, has become increasingly prevalent. Worryingly, there is evidence that CA-MRSA is penetrating the healthcare MRSA reservoir, and even replacing traditional HA-MRSA strains. This highlights the need to keep abreast of the changing epidemiology of MRSA in order to implement effective infection control strategies. To investigate the composition of the healthcare MRSA reservoir and ascertain the extent to which CAMRSA has penetrated this reservoir, a countywide, population-based cohort study of MRSA in hospital inpatients and nursing home residents was conducted in Orange County (OC), California, covering a total of 46 facilities. CA-MRSA was found to be fully mixed with HA-MRSA in the hospital setting. The predominant CA-MRSA clone in the US, USA300, was the most commonly isolated MRSA clone in OC hospitals. In OC nursing homes, HA-MRSA (specifically a variant of USA100 that is also very common in OC hospitals but has not been reported elsewhere) predominates, but USA300 made up just over a quarter of the isolates and was the second most frequently isolated clone. Both OC hospitals and nursing homes were dominated by the same three strains: USA300, USA100 and a variant of USA100. Not only are community-based infection control strategies needed to stem the influx of community associated strains, in particular USA300, into the hospital setting, but also strategies tailored to the complex problem of MRSA transmission and infection in nursing homes, to minimise the impact of the unique nursing home MRSA reservoir on overall regional MRSA burden. A key component of effective infection control strategies is prompt isolation of MRSA carriers, facilitated by rapid diagnostics. PCR-based methods of MRSA detection offer a much faster alternative to traditional culture techniques, but are expensive and often complex to operate. A novel nucleic acid amplification technique developed by my industrial sponsor, TwistDx Ltd, called recombinase polymerase amplification (RPA), has been incorporated into a probe based detection system called TwistAmp MRSA, and offers a simple and cheap alternative to current commercial PCR-based assays, amplifying MRSA to detectable levels within 20 minutes. I tested the assay with diverse collections of MRSA and discovered that 4% of isolates from a UK MRSA collection could not be detected by the assay. I subsequently developed RPA primers for their detection. Nonetheless, TwistAmp MRSA was able to detect most MRSA strains, and was comparable to current commercial assays in this respect. Despite a very high analytical sensitivity of approximately 20 CFU/swab, the clinical sensitivity of TwistAmp MRSA was lower than expected with respect to the current market leader, Xpert MRSA. I investigated lysis and filtration methods to improve the assay's clinical sensitivity, but found that such methods did not currently warrant inclusion in the TwistAmp MRSA protocol. While TwistAmp MRSA performance is in line with current assays, and is a faster, cheaper and simpler assay, a problem faced by all molecular methods of MRSA detection is the constant emergence of undetectable MRSA strains, necessitating continual assay evaluation and improvement where possible.
8

The effect of socio-economic status on outcomes in cystic fibrosis

Taylor-Robinson, David January 2013 (has links)
Introduction: Reducing inequalities in health is a public health imperative. In the UK and internationally policies are being implemented to try to reduce health inequalities, with limited success. This thesis examines the effect of socio-economic status (SES) on clinical outcomes, healthcare use and employment opportunities in people with cystic fibrosis (CF). Poorer socio-economic circumstances have been linked with worse outcomes in cystic fibrosis. Because CF is genetically determined, this offers an opportunity to investigate the impact of SES on health and social outcomes, in a chronic condition without a socio-economic gradient in incidence. This provides a useful case for understanding how health inequalities are generated, in order to develop more effective interventions, for people with CF and more generally. Methods: I analyse, for the first time, the national CF registers from the UK and Denmark, using longitudinal modeling techniques. Mixed-effects models are used to assess the association between measures of SES and longitudinal outcomes, adjusting for clinically important covariates. Study 1 explores longitudinal weight, height, BMI, %FEV1, risk of Pseudomonas colonisation, and the use of major CF treatment modalities, and their association with small-area deprivation (8055 people with 49,337 observations between 1996 and 2010). Study 2 explores longitudinal employment status in adults with CF in the UK, and its association with small-area deprivation, disease severity, and time in hospital. Study 3 presents a novel longitudinal analysis of the Danish CF registry (70,448 %FEV1 measures on 479 patients seen monthly between 1969 and 2010), to understand the way %FEV1 changes over time. Results: Compared with the least deprived areas in the UK, children with CF from the most deprived areas weighed less, were shorter, had a lower body-mass index, were more likely to have chronic P. aeruginosa infection, and have a lower %FEV1. These inequalities were apparent very early in life and did not widen thereafter. On a population level, after adjustment for disease severity, children in the most deprived quintile were more likely to receive intravenous antibiotics and nutritional treatments compared with individuals in the least deprived quintile. Patients from the most disadvantaged areas were less likely to receive DNase or inhaled antibiotic treatment. In adults deprivation, disease severity, and time in hospital all influence employment chances in CF. Furthermore, deprivation amplifies the harmful effects of disease severity on employment: the employment chances of people with CF with poor lung function from disadvantaged areas are damaged to a greater extent than for their counterparts living in the least disadvantaged circumstances. The Danish analysis quantifies the short-term variability in %FEV1 (SD 6.3%) and shows that lung function measures are correlated for over 15 years. Conclusions: In the UK, children with CF from more disadvantaged areas have worse growth and lung function compared with children from more affluent areas, but these inequalities do not widen with advancing age. Policies to reduce inequalities should thus focus on the early years. Clinicians consider deprivation status, as well as disease status, when making decisions about treatments, and this might mitigate some effects of social disadvantage. The differential social consequence of having CF in terms of employment is likely to be an important pathway for the amplification of health inequalities.
9

The cultural anatomy of decision making : the 'problem' of organ donation and ethnicity

Cooper, Jessie January 2012 (has links)
Organ transplantation is considered the optimal treatment for those in kidney failure, yet there is a growing gap between the global demand for transplantable organs and their supply. Transplant medicine has largely concentrated upon solving this problem by securing the willingness of the public to donate their organs after death. In the UK context, attention has been trained upon black and minority ethnic (‘BME’) groups, who make up 28% of the kidney transplant waiting list, yet just 4% of organ donors. Since transplant medicine has traditionally favoured sharing organs between similar ethnic groups, ‘BME’ patients have a greatly reduced chance of receiving a transplant, despite their higher levels of need. Searching for ways to solve this problem, policy and research responses have focused upon understanding the ‘cultural’ barriers which ‘BME’ ‘communities’ present for organ donation, with subsequent interventions aimed at promoting organ donation to these groups. In so doing, minority ethnic groups have been positioned as the cause of transplant inequalities, and handed responsibility for solving an issue originally created within the practices of transplant medicine itself. This study aims to resituate this ‘problem’ by focusing upon the institutional organ donation encounter: where potential donors are decided upon and families are requested to donate their relative’s organs. A multi-sited ethnographic approach was taken to examine the work involved in organ donation in two acute hospital Trusts in the North of England, and wider ‘community’ domains, such as religious temples. Narrative and observational methods were used to understand the experiences of Intensive Care staff and donation nurses involved in requesting donation from minority ethnic families, and those connected to the ‘problem’, such as religious leaders and minority ethnic transplant recipients. Findings reveal (‘BME’) organ donation to be an embedded, negotiated practice, which goes far beyond the willingness, or reluctance, of an individual to donate their organs after death. Instead, this study demonstrates that donation is dependent upon the practices of health professionals, who make decisions on the suitability of dead and dying patients for donation. Moreover, it shows how donation decisions are produced in the negotiations between families and health professionals over the medical diagnosis of death; in the discussions of the immediate and extended family of the potential donor; and by the ability of donation nurse to secure a family’s consent for donation. This study therefore illustrates how the ‘problem’ of ethnicity in organ donation is far from an isolated matter, created as a result of the ‘culture’ of ‘BME’ populations. Instead, it argues that the categories of the ‘BME organ donor’ and the ‘BME donor family’ – as problematic for donation – are maintained and reproduced within the very processes which make organ donation possible.
10

Assessing the strength of non-contemporaneous forensic speech evidence

Rhodes, Richard William January 2012 (has links)
The aim of this thesis is to assess the impact of long term non-contemporaneity on the strength of forensic speech evidence. Speakers experience age-related changes to the voice over long delays and this time also presents the opportunity for social factors to vary. These changes are shown to impact on speech parameters used in forensic analyses. Using longitudinal data from the Up documentary series, this thesis analyses the effects of aging on forensically useful acoustic parameters in eight speakers at five seven-year intervals between ages 21 and 49. The investigation reveals significant age-related changes in real-time across adulthood. Frequencies of the first three formants in monophthongs /i: ɪ e a ɑ: ʌ ɒ ʊ & u:/ and diphthongs /eɪ & aɪ/ show comprehensive reduction. For monophthongs, F1 exhibits mean change of 8.5%, greater than F2 and F3 at 3.7% and 2.2% respectively. Vowel quality also impacts on magnitude of change in each formant. Estimations based on this data suggest that vocal tract extension and restricted articulator movement are probable drivers for acoustic change, operating on different timelines. Counter-examples to this aging pattern can generally be explained by social factors, as a result of mobility or in accordance with mainstream changes in a variety. Strength of evidence estimates for these non-contemporaneous data are calculated using a numerical likelihood ratio (LR) approach. Age-related changes result in weaker and fewer correct LRs with greater length delays. Cubic coefficients of diphthong formants are investigated in line with a formant dynamic approach. These LR tests show promising results and resilience to aging, especially in F1; tentatively suggesting that, for these speakers, some speaker-specific behaviour pervades in spite of physiological changes. This analysis raises several questions with regards to applying an overtly numerical LR approach where there is apparent mismatch between forensic samples. The effect of aging on an ASR system (BATVOX) is also tested for six male subjects. The system measures Mel-frequency cepstral coefficient (MFCC) parameters that reflect the physical properties of the vocal tract. Predicted degradation of the system’s performance with increasing age is apparent. The reduction in performance is significant, varies between speakers, and is striking in longer delays for all speakers. The degradation in strength of evidence for acoustic data from monophthongs and formant dynamic coefficients, as well as that for the ASR system, demonstrates that aging presents a real problem for forensic analysis in non-contemporaneous cases. Furthermore, aging also presents issues for speech databases for the purpose of assessing strength of evidence, where further research into distributions of parameters in different age groups is warranted.

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