43 resultados para deviance information criteria, model averaging, MCMC, genomewide association studies, epistasis, logistic regression, stochastic search algorithm, case-control studies, Type I diabetes, single nucleotide polymorphism, gene expression programming


Relevância:

100.00% 100.00%

Publicador:

Resumo:

In the study, a cohort of 440 child sexual abuse cases were used to model the effect of victim age on police authorisation of charges. Linear and quadratic effects of age were modelled in a logistic regression that controlled for case characteristics and evidence. The quadratic effect of victim age was strengthened when control variables were included in the model and the linear effect of age was not significant in the final model. The results indicated that cases involving victims in middle childhood had a higher proportion of suspects charged than cases involving victims in early childhood and adolescence. Possible mediators of the relationship between victim age and charges were explored and it was found that cases with older victims had a higher prevalence of extra-familial abuse and suspect confessions, and these factors had a positive effect on the proportion of suspects charged. Possible explanations for the quadratic effect of victim age and mediation are discussed.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

BACKGROUND: Health state valuation data are often excluded from studies that aim to provide a nationally representative set of values for preference-based health-related quality of life (HRQoL) instruments. The purpose was to provide a systematic examination of exclusion criteria used in the derivation of societal scoring algorithms for preference-based HRQoL instruments. METHODS: Data sources included MEDLINE, official instrument websites, and publication reference lists. Analyses that used data from national valuation studies and reported a scoring algorithm for a generic preference-based HRQoL instrument were included. Data extraction included exclusion criteria and associated justifications, exclusion rates, the characteristics of excluded respondents, and analyses that explored consequential implications of exclusion criteria on the respective national tariff. RESULTS: Seventy-six analyses (from 70 papers) met the inclusion criteria. In addition to being excluded for logical inconsistencies, respondents were often excluded if they valued fewer than 3 health states or if they gave the same value to all health states. Numerous other exclusion criteria were identified, with varying degrees of justification, often based on an assumption that respondents did not understand the task or as a consequence of the chosen statistical modeling techniques. Rates of exclusion ranged from 0% to 65%, with excluded respondents more likely to be older, less educated, and less healthy. Limitations included that the database search was confined to MEDLINE; study selection focused on national valuation studies that used standard gamble, time tradeoff, and/or visual analog scale techniques; and only English-language studies were included. CONCLUSION: Exclusion criteria used in national valuation studies vary considerably. Further consideration is necessary in this important and influential area of research, from the design stage to the reporting of results.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objective: To determine whether interventions tailored specifically to  particular immigrant groups from developing to developed countries  decrease the risk of obesity and obesity-related diseases.

Design: Databases searched were MEDLINE (1966–September 2008), CINAHL (1982–September 2008) and PsychINFO (1960–September 2008), as well as Sociological Abstracts, PsychARTICLES, Science Direct, Web of Knowledge and Google Scholar. Studies were included if they were randomised control trials, ‘quasi-randomised’ trials or controlled before-and-after studies. Due to the heterogeneity of study characteristics only a narrative synthesis was undertaken, describing the target population, type and reported impact of the intervention and the effect size.

Results: Thirteen studies met the inclusion criteria. Ten out of thirteen (77 %) studies focused on diabetes, seven (70 %) of which showed significant improvement in addressing diabetes-related behaviours and glycaemic control. The effect on diabetes was greater in culturally tailored and facilitated interventions that encompassed multiple strategies. Six out of the thirteen studies (46 %) incorporated anthropometric data, physical activity and healthy eating as ways to minimise weight gain and diabetes-related outcomes. Of the six interventions that included anthropometric data, only two (33 %) reported improvement in BMI Z-scores, total skinfold thickness or proportion of body fat. Only one in three (33 %) of the studies that included cardiovascular risk factors reported improvement in diastolic blood pressure after adjusting for baseline characteristics. All studies, except four, were of poor quality (small sample size, poor internal consistency of scale, not controlling for baseline characteristics).

Conclusions: Due to the small number of studies included in the present review, the findings that culturally tailored and facilitated interventions produce better outcomes than generalised interventions, and that intervention content is more important than the duration or venue, require further investigation.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Summary We examined the independent contributions of First Nations ethnicity and lower income to post-fracture mortality. A similar relative increase in mortality associated with fracture appears to translate into a larger absolute increase in post-fracture mortality for First Nations compared to non-First Nations peoples. Lower income also predicted increased mortality post-fracture.

Introduction First Nations peoples have a greater risk of mortality than non-First Nations peoples. We examined the independent contributions of First Nations ethnicity and income to mortality post-fracture, and associations with time to surgery post-hip fracture.

Methods Non-traumatic fracture cases and fracture-free controls were identified from population-based administrative data repositories for Manitoba, Canada (aged ≥50 years). Populations were retrospectively matched for sex, age (within 5 years), First Nations ethnicity, and number of comorbidities. Differences in mortality post-fracture of hip, wrist, or spine, 1996–2004 (population 1, n = 63,081), and the hip, 1987–2002(Population 2, n = 41,211) were examined using Cox proportional hazards regression to model time to death. For hip fracture, logistic regression analyses were used to model the probability of death within 30 days and 1 year.

Results Population 1: First Nations ethnicity was associated with an increased mortality risk of 30–53 % for each fracture type. Lower income was associated with an increased mortality risk of 18–26 %. Population 2: lower income predicted mortality overall (odds ratio (OR) 1.15, 95 % confidence interval (CI) 1.07–1.23) and for hip fracture cases (OR 1.18, 95%CI 1.05–1.32), as did older age, male sex, diabetes, and >5 comorbidities (all p ≤ 0.01). Higher mortality was associated with pertrochanteric fracture (OR 1.14, 95 % CI 1.03–1.27), or surgery delay of 2–3 days (OR 1.34, 95 % CI 1.18–1.52) or ≥4 days (OR 2.35, 95 % CI 2.07–2.67).

Conclusion A larger absolute increase in mortality post-fracture was observed for First Nations compared to non-First Nations peoples. Lower income and surgery delay >2 days predicted mortality post-fracture. These data have implications regarding prioritization of healthcare to ensure targeted, timely care for First Nations peoples and/or individuals with lower income.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objective:

The SH3-domain GRB2-like (endophilin)-interacting protein 1 (SGIP1) gene has been shown to be differentially expressed in the hypothalamus of lean versus obese Israeli sand rats (Psammomys obesus), and is suspected of having a role in regulating food intake. The purpose of this study was to assess the role of genetic variation in SGIP1 in human disease.
Subjects:

We performed single-nucleotide polymorphism (SNP) genotyping in a large family pedigree cohort from the island of Mauritius. The Mauritius Family Study (MFS) consists of 400 individuals from 24 Indo-Mauritian families recruited from the genetically homogeneous population of Mauritius. We measured markers of the metabolic syndrome, including diabetes and obesity-related phenotypes such as fasting plasma glucose, waist:hip ratio, body mass index and fat mass.
Results:

Statistical genetic analysis revealed associations between SGIP1 polymorphisms and fat mass (in kilograms) as measured by bioimpedance. SNP genotyping identified associations between several genetic variants and fat mass, with the strongest association for rs2146905 (P=4.7 × 10−5). A strong allelic effect was noted for several SNPs where fat mass was reduced by up to 9.4% for individuals homozygous for the minor allele.
Conclusions:

Our results show association between genetic variants in SGIP1 and fat mass. We provide evidence that variation in SGIP1 is a potentially important determinant of obesity-related traits in humans.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

OBJECTIVE:
To determine whether improvements in glycemic control and diabetes-specific quality of life (QoL) scores reported in research studies for the type 1 diabetes structured education program Dose Adjustment For Normal Eating (DAFNE) are also found when the intervention is delivered within routine U.K. health care.

RESEARCH DESIGN AND METHODS:
Before and after evaluation of DAFNE to assess impact on glycemic control and QoL among 262 adults with type 1 diabetes.

RESULTS:
There were significant improvements in HbA1c from baseline to 6 and 12 months (from 9.1 to 8.6 and 8.8%, respectively) in a subgroup with suboptimal control. QoL was significantly improved by 3 months and maintained at both follow-up points.

CONCLUSIONS:
Longer-term improved glycemic control and QoL is achievable among adults with type 1 diabetes through delivery of structured education in routine care, albeit with smaller effect sizes than reported in trials.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Lung cancer is a leading cause of cancer-related death worldwide. The early diagnosis of cancer has demonstrated to be greatly helpful for curing the disease effectively. Microarray technology provides a promising approach of exploiting gene profiles for cancer diagnosis. In this study, the authors propose a gene expression programming (GEP)-based model to predict lung cancer from microarray data. The authors use two gene selection methods to extract the significant lung cancer related genes, and accordingly propose different GEP-based prediction models. Prediction performance evaluations and comparisons between the authors' GEP models and three representative machine learning methods, support vector machine, multi-layer perceptron and radial basis function neural network, were conducted thoroughly on real microarray lung cancer datasets. Reliability was assessed by the cross-data set validation. The experimental results show that the GEP model using fewer feature genes outperformed other models in terms of accuracy, sensitivity, specificity and area under the receiver operating characteristic curve. It is concluded that GEP model is a better solution to lung cancer prediction problems.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

I show that the principal and the agent may each prefer that the principal or the agent has imperfect information about the principal's technology in a principal-agent environment with moral hazard. Principals expend considerable resources on data cumulation and analysis. However, such investments in information acquisition are benecial only if the agent will know that the principal is not ignorant or it allows the principal to implement a dierent action. When the principal is perfectly informed about her technology, the agent prefers to be ignorant. In addition, the value of perfect information for the agency is negative if the principal would implement the same action with either possible technology. I also investigate the dierences between ex ante and ex post contracting, and the ramications of the principal being ignorant or potentially ignorant about the technology. Finally, I determine if the principal's utility varies continuously with the degree of informativeness of the agent about the principal's technology. In this vein, I determine whether the agent's uncertainty may make the principal better o if she has the less informative technology.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

While the important role of family carers has been increasingly recognized in healthcare service provision, particularly for patients with acute or chronic illnesses, the family carer's information needs have not been well understood or adequately supported by health information systems. In this study, we explore the information needs of a family carer by analyzing the extensive online diary of a Vietnamese family carer supporting his wife, who was a lung cancer patient. The study provides a deep understanding of the information needs of the family carer and suggests a four-stage information journey model including identification, searching, interpretation and information sharing, and collaboration. A number of themes emerge from the study including the key role of the carer, information filtering by the carer, information sharing and collaboration, and the influence of Vietnamese culture. The paper concludes with a discussion of the requirements for health information systems that meet the needs of family carers.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Purpose – This paper aims to investigate whether the accounting reform in China has improved the relevance of China's accounting information. It seeks to investigate the association between earnings and book value of equity to share returns before and after the introduction of the Accounting System for Business Enterprises (ASBE) in 2001 for A- and A&B-share firms.

Design/methodology/approach – The paper employs the return regression model. The pre-ASBE period is designated as 1997 through to 2000, and the post-ASBE period is designated as 2002 through to 2004. All firms listed on the Chinese stock market during the investigation period constitute the sample.

FindingsIt is found that accounting information better explains share returns for both A-share firms and A&B-share firms in the post-ASBE period. The paper also finds that the book value of equity for A&B-share firms is incrementally value relevant to that of A-share firms in the post-ASBE period.

Research limitations/implications – Further studies will contribute to understanding how governance mechanisms and liquidity influence the association between accounting information and share returns in the Chinese A-share market.

Practical implications
– The findings provide empirical evidence regarding the relevance of accounting information in emerging markets.

Originality/value – The paper contributes to the extant value relevance literature by investigating time periods surrounding the issue of ASBE in 2001 in the Chinese stock market.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Constructability is an important approach that allows the building industry to achieve quality outputs making best use of resources – the linked goals of time, cost and quality. Information supply and knowledge transfer are central to this and are recognized as integral to an industry strategy to improve productivity. However, poor delivery of information to those at the construction site and lack of effective methods of transferring knowledge between parties involved in construction become major challenges. This paper reviews the building production practices and information networks adopted by three countries to achieve better constructability practices. The elements of ‘control’, ‘innovation’, ‘best practice’ and ‘audit’, identified as key to improving knowledge transfer, are modelled for the construction sectors of Singapore, Australia and Malaysia. A framework for knowledge transfer is proposed to promote better practices in the construction industry.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background: Planning of disease prevention strategies requires information regarding the distribution of absolute risk in the population to allow targeting of people at high disease risk. It is well known that death rates from coronary heart disease (CHD) are higher in remote areas of Australia compared with major cities. Less well understood is the distribution of the absolute risk of CHD death within the different geographic regions. We present a mathematical model of CHD which projects the lifetime risk of death among individuals in different percentiles of CHD risk. We apply this to model the distribution of CHD risk within different geographic regions.

Methods: Using information from the Framingham1, MRFIT2 and AusDiab3 studies, the Australian population was divided into percentiles of CHD risk within age and gender groups by geographic location. Absolute mortality risk was determined at each percentile using current Australian mortality data. Survival curves were generated for each percentile using these risk estimates. Approximate confidence intervals were derived using bootstrap methods.

Conclusions: The difference in life expectancy at age 25 between those in the lowest decile of CHD risk compared to the highest was 5.8 years (95%CI:4.7,6.7) in major cities compared to 8.5 years (95%CI:7.6,9.7) in remote areas. The difference in risk of premature death (before age 75) was 12% (95%CI:10%,14%) in major cities compared to 33% (95%CI:28%,38%) in remote areas.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

 The current study used Bayesian hierarchical methods to challenge and extend previous work on subtask learning consistency. A general model of individual-level subtask learning was proposed focusing on power and exponential functions with constraints to test for inconsistency. To study subtask learning, we developed a novel computer-based booking task, which logged participant actions, enabling measurement of strategy use and subtask performance. Model comparison was performed using deviance information criterion (DIC), posterior predictive checks, plots of model fits, and model recovery simulations. Results showed that although learning tended to be monotonically decreasing and decelerating, and approaching an asymptote for all subtasks, there was substantial inconsistency in learning curves both at the group- and individual-levels. This inconsistency was most apparent when constraining both the rate and the ratio of learning to asymptote to be equal across subtasks, thereby giving learning curves only 1 parameter for scaling. The inclusion of 6 strategy covariates provided improved prediction of subtask performance capturing different subtask learning processes and subtask trade-offs. In addition, strategy use partially explained the inconsistency in subtask learning. Overall, the model provided a more nuanced representation of how complex tasks can be decomposed in terms of simpler learning mechanisms.