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Purpose: Different health state utility (HSU) instruments produce different utilities for the same individuals, thereby compromising the intended comparability of economic evaluations of health care interventions. When developing crosswalks, previous studies have indicated nonlinear relationships. This paper inquires into the degree of nonlinearity across the four most widely used HSU-instruments and proposes exchange rates that differ depending on the severity levels of the health state utility scale.Methods: Overall, 7933 respondents from six countries, 1760 in a non-diagnosed healthy group and 6173 in seven disease groups, reported their health states using four different instruments: EQ-5D-5L, SF-6D, HUI-3 and 15D. Quantile regressions investigate the degree of nonlinear relationships between these instruments. To compare the instruments across different disease severities, we split the health state utility scale into utility intervals with 0.2 successive decrements in utility starting from perfect health at 1.00. Exchange rates (ERs) are calculated as the mean utility difference between two utility intervals on one HSU-instrument divided by the difference in mean utility on another HSU-instrument.Results: Quantile regressions reveal significant nonlinear relationships across all four HSU-instruments. The degrees of nonlinearities differ, with a maximum degree of difference in the coefficients along the health state utility scale of 3.34 when SF-6D is regressed on EQ-5D. At the lower end of the health state utility scale, the exchange rate from SF-6D to EQ-5D is 2.11, whilst at the upper end it is 0.38.Conclusion: Comparisons at different utility levels illustrate the fallacy of using linear functions as crosswalks between HSU-instruments. The existence of nonlinear relationships between different HSU-instruments suggests that level-specific exchange rates should be used when converting a change in utility on the instrument used, onto a corresponding utility change had another instrument been used. Accounting for nonlinearities will increase the validity of the comparison for decision makers when faced with a choice between interventions whose calculations of QALY gains have been based on different HSU-instruments. [ABSTRACT FROM AUTHOR]

This paper discusses recent migration to North America with reference to the 1962 and 1967 Canadian immigration regulations and the 1965 United States Immigration and Nationality Act. Despite the similar emphasis on manpower and kinship criteria as the basis for the admission of immigrants, differences between Canada and the United States exist with respect to the importance of immigration for the respective economies, the organization of immigration, the formal regulations, and the size and composition of migrant streams. After an examination of the volume, origin, and occupational composition of immigration to Canada and the United States, flows between the two countries are studied. The paper concludes with a scrutiny of changes in immigration regulations which are pending in both countries. [ABSTRACT FROM AUTHOR]

Health care expenditure studies of the Organization for Economic Cooperation and Development (OECD) countries remain important because their findings often suggest cost containment and other policy initiatives. This paper focuses on the compatibility of OECD health data with the "expenditure inertia" (or lagged adjustments) hypothesis, by modeling individual country time-series data of 21 nations for the 1960-1993 period. Maximum likelihood estimates of the Box-Cox transformation regression models reveal that: (a) the hypothesized impact of health "expenditure inertia" is both pervasive and strong, averaging 0.64 across the countries; (b) the real GDP elasticities of health care expenditures vary widely among the countries and average 0.34 in the short run--implying that health care is a necessity; (c) the long run GDP elasticities are less than 1 in 8 countries, unitary elastic in 8 countries and elastic in 5 countries--suggesting that health care is not universally a necessity or a luxury commodity for the OECD countries; (d) physician-inducement effects (dis-inducement in a few countries) are weak, with a mean elasticity estimate of 0.17; and (e) no unique functional form approximation model is globally compatible with the data across the countries. Health care cost containment policy implications of these findings are explored. [ABSTRACT FROM AUTHOR]

A shortage of donor liver grafts unfortunately results in approximately 10% of patients dying whilst listed for a liver transplant in Europe and the United States. Thus it is imperative that all available organs are used as efficiently as possible. This paper reports upon the application of a simulation modelling approach to assess the impact of several alternative allocation policies upon the cost effectiveness of this technology at one liver transplant centre in the UK. The impact of changes in allocation criteria on the estimated net life expectancy, average net costs and overall cost effectiveness of the transplantation programme were evaluated. The incremental cost effectiveness ratio (ICER) for the base case allocation policy, based upon the time spent on the waiting list (i.e., longest wait first) was 11,557 pounds sterling at 1999 prices. The ICERs associated with an allocation policy based upon age (lowest age first), and an allocation policy based upon the severity of the pre-transplant condition of the patient (with most severely ill patients given a lower priority) were lower than the base case at 10,424 pounds sterling and 9,077 pounds sterling, respectively. The results of this modelling study suggest that the overall cost effectiveness of the liver transplantation programme could be improved if the current allocation policy were modified to give more weight to the age of the patient and the reduced chances of success of the most severely ill patients. [ABSTRACT FROM AUTHOR]

In the early 1970s, aluminium toxicity was first implicated in the pathogenesis of clinical disorders in patients with chronic renal failure involving bone (renal osteomalacia) or brain tissue (dialysis encephalopathy). Before that time the toxic effects of aluminium ingestion were not considered to be a major concern because absorption seemed unlikely to occur. Meanwhile, aluminium toxicity has been investigated in countless epidemiological and clinical studies as well as in animal experiments and many papers have been published on the subject. It is now commonly acknowledged that aluminium toxicity can be induced by infusion of aluminium-contaminated dialysis fluids, by parenteral nutrition solutions, and by oral exposure as a result of aluminium-containing pharmaceutical products such as aluminium-based phosphate binders or antacid intake. Over-the-counter antacids are the most important source for human aluminium exposure from a quantitative point of view. However, aluminium can act as a powerful neurological toxicant and provoke embryonic and fetal toxic effects in animals and humans after gestational exposure. Despite these facts, the patient information leaflets from European antacids that are available OTC show substantial differences regarding warnings from aluminium toxicity. It seems advisable that all patients should receive the same information on aluminium toxicity from patient information leaflets, in particular with regard to the increased absorption through concomitant administration with citrate-containing beverages and the use of such antacids during pregnancy. [ABSTRACT FROM AUTHOR]

The cumulative (dis)advantage hypothesis states that health disparities between education groups increase with age. The present study examined this hypothesis in a comparative analysis of the United States, the United Kingdom, the Netherlands, and Sweden. These countries offer sharp contrasts in the social conditions that may intensify or inhibit processes of cumulative (dis)advantage. Using harmonized panel data from the HRS, ELSA, and SHARE, the study applied Poisson multilevel regression models to trace changes in the number of chronic conditions and functional limitations of people aged 50-76 (N = 16,887 individuals; 71,154 observations). The four countries showed a clear gradient in levels of physical health and in the extent to which health trajectories were shaped by education. Across all ages and cohorts, health problems were most prevalent in the United States, less prevalent in the United Kingdom and the Netherlands, and least prevalent in Sweden. A similar cross-national gradient was found for the size of health gaps between education groups and for the extent to which these gaps widened with age. Gaps were largest in the United States, smaller in the United Kingdom and in the Netherlands, and smallest in Sweden. [ABSTRACT FROM AUTHOR]

Public debates about both immigration policy and social safety net programs are increasingly contentious. However, little research has explored differences in health within America's diverse population of foreign-born workers, and the effect of these workers on public benefit programs is not well understood. We investigate differences in work disability by nativity and origins and describe the mix of health problems associated with receiving Social Security Disability Insurance benefits. Our analysis draws on two large national data sources-the American Community Survey and comprehensive administrative records from the Social Security Administration-to determine the prevalence and incidence of work disability between 2001 and 2010. In sharp contrast to prior research, we find that foreign-born adults are substantially less likely than native-born Americans to report work disability, to be insured for work disability benefits, and to apply for those benefits. Overall and across origins, the foreign-born also have a lower incidence of disability benefit award. Persons from Africa, Northern Europe, Canada, and parts of Asia have the lowest work disability benefit prevalence rates among the foreign-born; persons from Southern Europe, Western Europe, the former Soviet Union, and the Caribbean have the highest rates. [ABSTRACT FROM AUTHOR]

In recent years, population health research has focused on understanding the determinants of later-life health. Two strands of that work have focused on (1) international comparisons of later-life health and (2) assessing the early-life origins of disease and disability and the importance of life course processes. However, the less frequently examined intersection of these approaches remains an important frontier. The present study contributes to the integration of these approaches. We use the Health and Retirement Study family of data sets and a cohort dynamic approach to compare functional health trajectories across 12 high-income countries and to examine the role of life course processes and cohort dynamics in contributing to variation in those trajectories. We find substantial international variation in functional health trajectories and an important role of cohort dynamics in generating that variation, with younger cohorts often less healthy at comparable ages than the older cohorts they are replacing. We further find evidence of heterogeneous effects of life course processes on health trajectories. The results have important implications for future trends in morbidity and mortality as well as public policy. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate early performance of contemporary dual mobility acetabular systems with second generation annealed highly cross-linked polyethylene for primary hip arthroplasty of patients under 55 years of age.Methods: A prospective observational five years study across five centers in Europe and the USA of 321 patients with a mean age of 48.1 years was performed. Patients were assessed for causes of revision, hip instability, intra-prosthetic dissociation, Harris hip score and radiological signs of osteolysis.Results: There were no dislocations and no intra-prosthetic dissociations. Kaplan Meier analysis demonstrated 97.51% survivorship for all cause revision and 99.68% survivorship for acetabular component revision at five years. Mean Harris hip score was 93.6. Two acetabular shells were revised for neck-rim implant impingement without dislocation and ten femoral stems were revised for causes unrelated to dual mobility implants.Conclusion: Contemporary highly cross-linked polyethylene dual mobility systems demonstrate excellent early clinical, radiological, and survivorship results in a cohort of patients that demand high performance from their implants. It is envisaged that DM and second generation annealed HXLPE may reduce THA instability and wear, the two most common causes of THA revision in hip arthroplasty. [ABSTRACT FROM AUTHOR]

Many HIV intervention programs in sub-Saharan Africa have applied social cognitive theories such as the theory of planned behavior. However, a recent sub-Saharan African review was unable to show increased effectiveness for theory-based interventions. This study assessed whether the predictive value of attitudes, subjective norms, self-efficacy, and intention was similar to studies in Europe and the U.S., and whether there were differences between three sub-Saharan sites. Longitudinal multigroup structural equation modeling was used to assess whether attitudes, subjective norms, and self-efficacy predicted condom use intentions and condom use (after 6 months) among adolescents in three sites, namely Cape Town (South Africa; N = 625), Dar es Salaam (Tanzania; N = 271), and Mankweng (South Africa; N = 404). Condom use intentions were predicted by subjective norms and self-efficacy in all three sites. Attitudes were not related to intentions in Dar es Salaam and were moderately related to intentions in Cape Town and Mankweng. The proportions of explained variance in intentions and behavior were decent (37-52 and 9-19%, respectively). Although significant differences in predictive value were found between sites and in comparison to European and U.S. studies, intentions could adequately be explained by attitudes, subjective norms, and self-efficacy. However, the limited proportions of variance in behavior explained by intentions could signify the importance of contextual and environmental factors. Future studies are recommended to use an integrative approach that takes into account both individual and contextual factors, as well as social and environmental differences. [ABSTRACT FROM AUTHOR]

Cross-country comparisons of differential survival by socioeconomic status (SES) are useful in many domains. Yet, to date, such studies have been rare. Reliably estimating differential survival in a single country has been challenging because it requires rich panel data with a large sample size. Cross-country estimates have proven even more difficult because the measures of SES need to be comparable internationally. We present an alternative method for acquiring information on differential survival by SES. Rather than using observations of actual survival, we relate individuals' subjective probabilities of survival to SES variables in cross section. To show that subjective survival probabilities are informative proxies for actual survival when estimating differential survival, we compare estimates of differential survival based on actual survival with estimates based on subjective probabilities of survival for the same sample. The results are remarkably similar. We then use this approach to compare differential survival by SES for 10 European countries and the United States. Wealthier people have higher survival probabilities than those who are less wealthy, but the strength of the association differs across countries. Nations with a smaller gradient appear to be Belgium, France, and Italy, while the United States, England, and Sweden appear to have a larger gradient. [ABSTRACT FROM AUTHOR]

Rotavirus is one of the most common causes of gastroenteritis worldwide. With the commercialisation of effective rotavirus vaccines in Europe in sight, it is necessary to provide studies which evaluate the disease burden. The aim of this study is two-fold, on one hand, to determine the burden of the rotavirus disease in Spanish children under the age of five, and on the other, to estimate the economic cost of these hospitalizations. The study was undertaken during a 5 year period (2000-2004). The rotavirus hospitalization rate was determined using the Minimum Basic Data Set of the national hospital discharge register. The observed data were compared with those expected by applying a model developed by the Centers for Disease Control and Prevention (CDC) adapted for European Countries. The financial expense of these hospitalizations was estimated. Of all admissions coded as gastroenteritis, 31.6% were due to rotavirus. The hospitalization rate by rotavirus was 480 cases per 100,000 children under five. These data are within the confidence range proposed by the adapted CDC model. The financial expense due to hospitalizations reaches 123,262 euros yearly in a Spanish University Hospital. In conclusion, rotavirus contributes significantly to the hospitalization of acute gastroenteritis. The rate of hospitalization by rotavirus is higher compared to other studies carried out in Spain. In view of future commercialisation of rotavirus vaccines, more in-depth analysis considering direct and indirect costs are necessary. [ABSTRACT FROM AUTHOR]

The purpose of our study was to compare various aspects of radiology training schemes in ten countries. A questionnaire was sent to senior residents in the UK, USA, Canada, Australia, New Zealand, Italy, Egypt, India, Malaysia and Greece. The questions concerned length of training, required pre-training experience, the organization of the training scheme, teaching, resources, stages at which residents can independently perform and report examinations, fellowships, and progression to jobs. A wide variety of training, ranging from highly scheduled programs with detailed aims and objectives, to self-learning occurs across the world. Examinations and assessments are also variable. There are lessons to be learned from varying practices; more exchanges of ideas should be encouraged. In view of the "internationalization" of radiology services and the variation in training styles an international qualification for quality assurance purposes may be desirable. [ABSTRACT FROM AUTHOR]

Results from the Women's Health Initiative (WHI) trial support findings from observational studies that oestrogen-progestin therapy (EPT) use is associated with an increase in breast cancer risk. We conducted a meta-analysis using EPT-specific results from the Collaborative Group on Hormonal Factors in Breast Cancer (CGHFBC) pooled analysis and studies published since that report to obtain an overview of EPT use and breast cancer risk. We also assessed risk by histologic subtype of breast cancer, by schedule of the progestin component of EPT, and by recency of use. We estimate that overall, EPT results in a 7.6% increase in breast cancer risk per year of use. The risk was statistically significantly lower in US studies than in European studies - 5.2 vs 7.9%. There was a significantly higher risk for continuous-combined than for sequential EPT use in Scandinavian studies where much higher total doses of progestin were used in continuous-combined than in sequential EPT. We observed no overall difference in risk for lobular vs ductal carcinoma but did observe a slightly higher risk for current vs past EPT use. [ABSTRACT FROM AUTHOR]

The jurors identified numerous problems with end of life in the ICU including variability in practice, inadequate predictive models for death, elusive knowledge of patient preferences, poor communication between staff and surrogates, insufficient or absent training of health-care providers, the use of imprecise and insensitive terminology, and incomplete documentation in the medical records. The jury strongly recommends that research be conducted to improve end-of-life care. The jury advocates a "shared" approach to end-of-life decision-making involving the caregiver team and patient surrogates. Respect for patient autonomy and the intention to honour decisions to decline unwanted treatments should be conveyed to the family. The process is one of negotiation, and the outcome will be determined by the personalities and beliefs of the participants. Ultimately, it is the attending physician's responsibility, as leader of the health-care team, to decide on the reasonableness of the planned action. In the event of conflict, the ICU team may agree to continue support for a predetermined time. Most conflicts can be resolved. If the conflict persists, however, an ethics consultation may be helpful. Nurses must be involved in the process. The patient must be assured of a pain-free death. The jury of the Consensus Conference subscribes to the moral and legal principles that prohibit administering treatments specifically designed to hasten death. The patient must be given sufficient analgesia to alleviate pain and distress; if such analgesia hastens death, this "double effect" should not detract from the primary aim to ensure comfort. [ABSTRACT FROM AUTHOR]

Bipolar disorder is a chronic affective disorder that causes significant economic burden to patients, families and society. It has a lifetime prevalence of approximately 1.3%. Bipolar disorder is characterised by recurrent mania or hypomania and depressive episodes that cause impairments in functioning and health-related quality of life. Patients require acute and maintenance therapy delivered via inpatient and outpatient treatment. Patients with bipolar disorder often have contact with the social welfare and legal systems; bipolar disorder impairs occupational functioning and may lead to premature mortality through suicide. This review examines the symptomatology of bipolar disorder and identifies those features that make it difficult and costly to treat. Methods for assessing direct and indirect costs are reviewed. We report on comprehensive cost studies as well as administrative claims data and program evaluations. The majority of data is drawn from studies conducted in the US; however, we discuss European studies when appropriate. Only two comprehensive cost-of-illness studies on bipolar disorder, one prevalence-based and one incidence-based, have been reported. There are, however, several comprehensive cost-of-illness studies measuring economic burden of affective disorders including bipolar disorder. Estimates of total costs of affective disorders in the US range from $US30.4–43.7 billion (1990 values). In the prevalence-based cost-of-illness study on bipolar disorder, total annual costs were estimated at $US45.2 billion (1991 values). In the incidence-based study, lifetime costs were estimated at $US24 billion. Although there have been recent advances in pharmacotherapy and outpatient therapy, hospitalisation still accounts for a substantial portion of the direct costs. A variety of outpatient services are increasingly important for the care of patients with bipolar disorder and costs in this area continue to grow. Indirect costs due to morbidity and premature mortality comprise a large portion of the cost of illness. Lost workdays or inability to work due to the disease cause high morbidity costs. Intangible costs such as family burden and impaired health-related quality of life are common, although it has proved difficult to attach monetary values to these costs. [ABSTRACT FROM AUTHOR]

Walnuts (Juglans regia L.) were collected during the 1997 harvest from 12 different cultivars of trees grown in a replicated trial in an experimental orchard at Lincoln University. Two US commercial cultivars (Tehama and Vina), three European commercial cultivars (Esterhazy, G139, G120) and eight New Zealand selections (Rex, Dublin's Glory, Meyric, Stanley, 150, 151, 153) were evaluated. The total oil content ranged from 62.6 to 70.3% while the crude protein ranged from 13.6 to 18.1%. Dietary fiber ranged from 4.2 to 5.2% while the starch content made up no more than 2.8% of the remaining portion of the kernel. The amino acid content of the walnuts was similar between cultivars and the patterns of essential amino acids were characteristic of a high quality protein. [ABSTRACT FROM AUTHOR]

While the EuroQOL instrument (EQ-5D) is being considered and used in clinical trials in the United States and Canada, and in large international multicentre studies, population weights for the instrument have never been established in North America. The primary purpose of this investigation was to derive a set of US-based population weights for the standard set of health states described in the EQ-5D health questionnaire. Valuations for EQ-5D health states were obtained via a postal survey using the visual analogue scale (VAS) format. A sample of 3,500 adults from the continental US were surveyed. A response rate of 25.8% was obtained. Mean and median valuations for 45 distinct health states, including dead and unconscious, were calculated. An ordinary least squares (OLS) regression-based weighting scheme was constructed to impute scores for states not directly valued in the questionnaire formats. Valuations for the standard EQ-5D health states displayed similar characteristics to VAS valuations obtained in previous investigations in European countries. The OLS model fit the observed data relatively well, achieving an adjusted R2 of 0.42. However, the diagnostic testing indicated that the initial model was misspecified. Subsequent alternative models alleviated some, but not all, of the problems of misspecification. The EQ-5D valuations from adult Americans in this sample appeared to behave in much the same fashion as in previous valuation studies. However, the generalisability of results to the entire adult American population may be limited. Violations of assumptions of the OLS regression model indicate the need for further investigation into the modelling technique used in deriving a single index score. [ABSTRACT FROM AUTHOR]

The acute respiratory distress syndrome (ARDS), a process of non-hydrostatic pulmonary edema and hypoxemia associated with a variety of etiologies carries a high morbidity, mortality (10-90%) and financial cost. The reported annual incidence in the United States is 150,000 cases, but this figure has been challenged and may be different in Europe. Part of the reason for these uncertainties is the heterogeneity of diseases underlying ARDS and the lack of uniform definitions for ARDS. Thus, those whose wish to know the true incidence and outcome on this clinical syndrome are stymied. The European American Consensus Committee on ARDS was formed to focus on these issues and on the pathophysiologic mechanisms of the process. It was felt that international coordination between North America and Europe in clinical studies of ARDS was becoming increasingly important in order to address the recent plethora of potential therapeutic agents for the prevention and treatment of ARDS. [ABSTRACT FROM AUTHOR]