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John Nixon

Publications and source records attributed to John Nixon.

11 recordsLinked to original sources
PubMed2006

The relationship between health care expenditure and health outcomes. Evidence and caveats for a causal link.

The relationship between health care expenditure and health outcomes is of interest to policy makers in the light of steady increases in health care spending for most industrialised countries. However, establishing causal relationships is complex because, firstly, health care expenditure is only one of many quantitative and qualitative factors that contribute to health outcomes, and, secondly, measurement of health status is an imperfect process. This study reviews key findings and methodological approaches in this field and reports the results of our own empirical study of countries of the European Union. Our analysis examines life expectancy and infant mortality as the 'output' of the health care system, and various life-style, environmental and occupational factors as 'inputs'. Econometric analyses using a fixed effects model are conducted on a panel data set for the former 15 members of the European Union over the period 1980-1995. The findings show that increases in health care expenditure are significantly associated with large improvements in infant mortality but only marginally in relation to life expectancy. The findings are generally consistent with those of several previous studies. Caveats and improvements for future research are presented.

Causality↗
PubMed2005

Genome-wide analysis of the frequency and distribution of crossovers at male and female meiosis in Sinapis alba L. (white mustard).

We present the first genetic linkage maps of Sinapis alba (white mustard) and a rigorous analysis of sex effects on the frequency and distribution of crossovers at meiosis in this species. Sex-averaged maps representing recombination in two highly heterozygous parents were aligned to give a consensus map consisting of 382 loci defined by restriction fragment length polymorphisms and arranged in 12 linkage groups with no unlinked markers. The loci were distributed in a near-random manner across the genome, and there was little evidence of segregation distortion. From these dense maps, a subset of spaced informative markers was used to establish recombination frequencies assayed separately in male and female gametes and derived from two distinct genetic backgrounds. Analyses of 746 gametes indicated that recombination frequencies were greater in male gametes, with the greatest differences near the ends of linkage groups. Genetic background had a lesser effect on recombination frequencies, with no discernible pattern in the distribution of such differences. The possible causes of sex differences in recombination frequency and the implications for plant breeding are discussed.

Chromosome Mapping↗
PubMed2005

Can economic evaluations be made more transferable?

Several commentators have identified the lack of generalisability and transferability of economic evaluation results. The aims of this study were: (a) to develop a checklist to assess the level of generalisability and transferability of economic evaluations; (b) to assess the generalisability and transferability of economic evaluations between the UK and France using the checklist; (c) to identify reasons for any lack of transferability and generalisability; (d) to assess how the transferability and generalisability of economic evaluations can be improved; and (e) to outline ways in which databases of economic evaluations and journals can assist in this area. The checklist was developed using previous work and the templates of the NHS EED and CODECS databases. A sub-checklist of essential items was then derived. Validation of the two checklists was undertaken with Health Economists participating in the EURONHEED project. Economic evaluations involving the UK and France were then located and assessed using the checklist. A summary score for each study was calculated based on the percentage of correctly reported (applicable) points, and the results in the empirical analysis compared to identify differences. The extended checklist includes 42 items, and the sub-checklist 16 items. Twenty-five economic evaluations met the inclusion criteria for the empirical analysis. In the extended checklist the mean score was 66.9+/-13.6%. The results for the sub-checklist were very similar. The analysis revealed that costing, assessments of generalisability by the author(s), assessment of data variability, discounting, study population, and the reporting of effectiveness are areas that need more attention. Differences in cost-effectiveness results are often accounted for by price or organisational differences. The developed checklists are useful in assessing the generalisability and transferability of economic evaluations. In order to improve the generalisability and transferability of economic evaluations authors need to be more explicit and detailed in describing and reporting their studies. If they are to provide added value to their users, international databases of economic evaluations should systematically assess the generalisability and transferability of studies. Further research is in progress on producing a weighted version of the checklist.

Cost-Benefit Analysis↗
PubMed2005

The diffusion of health economics knowledge in Europe : The EURONHEED (European Network of Health Economics Evaluation Database) project.

This paper overviews the EURONHEED (EUROpean Network of Health Economics Evaluation Databases) project. Launched in 2003, this project is funded by the EU. Its aim is to create a network of national and international databases dedicated to health economic evaluation of health services and innovations. Seven centres (France, Germany, Italy, The Netherlands, Spain, Sweden and the UK) are involved covering 17 countries. The network is based on two existing databases, the French CODECS (COnnaissance et Decision en EConomie de la Sante) database, created in 2000 by the French Health Economists Association (College des Economistes de la Sante), and the UK NHS-EED (NHS Economic Electronic Database), run by the Centre for Reviews and Dissemination, University of York, York, England. The network will provide bibliographic records of published full health economic evaluation studies (cost-benefit, cost-utility and cost-effectiveness studies) as well as cost studies, methodological articles and review papers. Moreover, a structured abstract of full evaluation studies will be provided to users, allowing them access to a detailed description of each study and to a commentary stressing the implications and limits, for decision making, of the study. Access will be free of charge. The database features and its ease of access (via the internet: http://www.euronheed.org) should facilitate the diffusion of existing economic evidence on health services and the generalisation of common standards in the field at the European level, thereby improving the quality, generalisability and transferability of results across countries.

Databases as Topic↗
PubMed2004

The European Network of Health Economic Evaluation Databases (EURO NHEED) Project.

This paper provides a first outline of the European Network of Health Economic Evaluation Databases (EURO NHEED) project. The project is funded by the European Commission and will implement, in 7 European centres based in France, Germany, Italy, The Netherlands, Spain, Sweden and the United Kingdom, databases on the economic evaluation of healthcare interventions. The network will be based on two existing and well-established resources, namely the UK's NHS Economic Evaluation Database (NHS EED), and France's Connaissances et Décision en EConomie de la Santé (CODECS) database. EURO NHEED will initially cover 17 European countries and will provide its users with bibliographic records, detailing the main characteristics of all included studies. In addition, structured abstracts will be provided for articles identified as full economic evaluations (cost-benefit, cost-effectiveness or cost-utility), which will offer a detailed critique of the findings and the methodology used. These databases will be accessible free of charge on the Internet. The EURO NHEED project is the first attempt to develop such a resource on a multi-national basis. The project will bring together Health Economists and Information Scientists from the European Union and beyond and is anticipated to facilitate a number of benefits and advances in the field of Health Economics. These include harmonisation and increased understanding of the theory and methodology of economic evaluation in healthcare, the interpretation of the generalisability of studies to target settings, and the influence of healthcare system variations among the European countries. The project will therefore advance the state of the art in collecting, summarising, critiquing and disseminating economic evaluations of healthcare conducted within Europe.

Cost-Benefit Analysis↗
PubMed2004

The usefulness of the NHS Economic Evaluation Database to researchers undertaking technology assessment reviews.

OBJECTIVES: Health-care technology reviews now increasingly include outcome costs as well as clinical effects. This study reports the findings and implications of a survey to explore the usefulness of the National Health Service Economic Evaluation Database (NHS EED) within this process. METHODS: Postal survey of lead authors of Technology Assessment Reviews (TARs) commissioned by the United Kingdom's National Institute for Clinical Excellence (NICE). The questionnaire investigated the usefulness of NHS EED in terms of (a) search strategy, (b) data extraction, (c) quality assessment, and (d) determining requirements for new modeling studies. Qualitative data were requested, including opinions regarding NHS EED. RESULTS: NHS EED was used in 90 percent of all identified reviews (n = 46). The questionnaire response rate was 63 percent. The percentage of scores 3 or above (most useful), 2 or below (least useful), or N/A were, respectively, (a) search strategy= 62 percent, 23 percent, 15 percent; (b) data extraction = 23 percent, 27 percent, 50 percent, (c) quality assessment= 38 percent, 19 percent, 42 percent; (d) determining requirements for new modeling studies = 27 percent, 23 percent, 50 percent. The results were expanded further in the qualitative data from the respondents. CONCLUSIONS: NHS EED is a useful tool for a variety of tasks in the NICE/TAR process but not, unsurprisingly, as a replacement for understanding primary studies. There is, however, a need to reduce the impact of time lags between the publication of economic evaluations and the appearance of abstracts relating to them on NHS EED. The results will inform future developments of the NHS EED database, which should increase its usefulness to researchers.

Cost-Benefit Analysis↗
PubMed2002

Service provision of complex mutation analysis: a technical and economic appraisal using dystrophin point mutation analysis as an example.

Duchenne muscular dystrophy (DMD) results from mutations in the dystrophin gene. One-third of cases arise from point mutations, which are heterogeneous and difficult to detect. The aims of this study of dystrophin point mutation analysis were to assess its technical feasibility in a routine diagnostic laboratory, and to estimate its costs and clinical benefits. The methods used were a laboratory based study using reverse transcription-polymerase chain reaction (RT-PCR) and a protein truncation test, and a mathematical model to estimate costs and clinical benefits. None of the cases analyzed had an identifiable dystrophin deletion or duplication. They were 12 males affected with DMD and two obligate female carriers; two female carriers of known dystrophin point mutations were also analyzed. Point mutations were detected in six out of 12 males, but in none of the female carriers. Assuming a sensitivity of 50% the model predicts significant clinical benefits of point mutation analysis over linkage analysis, including a reduction in the number of prenatal diagnoses (by 0.77 per family), terminations of pregnancy (by 0.18 per family), and terminations of unaffected fetuses (by 0.16 per family). The mean cost of point mutation analysis to prevent the termination of an unaffected fetus is 6220 US dollars.

Dystrophin↗
PubMed2002

Using economic evidence to support decision making: a case study of assertive community treatment within the UK National Service Framework for Mental Health.

This study illustrates a process of accessing and utilising clinical and economic evidence in health care decision making. The scenario examined was that of a UK Health Authority evaluating evidence prior to the introduction of assertive community treatment (ACT), as part of guidance from the UK National Service Framework for Mental Health. The consistency between clinical and cost evidence from a number of sources (Cochrane Database of Systematic Reviews (CDSR), Database of Reviews of Effectiveness (DARE), HTA database, NHS Economic Evaluation database (NHS EED)) was also addressed, as was the usefulness of structured abstracts on NHS EED. The findings showed that within specified caveats ACT tends to be more effective and also less costly than alternative interventions; there is general agreement between sources principally reporting effectiveness and economic evaluations; and NHS EED abstracts are useful in the decision making process where information gaps exist. In terms of health care policy in the health authority examined, two ACT teams were subsequently introduced in the city of Leicester. Although systematic reviews and appraisals of evidence are arguably the gold standard in health care decision making, the study illustrates how the use of databases of structured abstracts can assist in making optimal choices in real life decision making scenarios.

Community Mental Health Services↗
PubMedDate not supplied

Do health-care decision makers find economic evaluations useful? The findings of focus group research in UK health authorities.

OBJECTIVES: The impact of economic evaluation studies on health-care decision makers has been shown to be rather limited. However, there is an increasing requirement for the cost-effectiveness of health-care interventions to be considered in formulating and implementing guidelines for clinical practice. This paper reports the findings of recent focus group research among UK health authorities, which examined the usefulness of published economic evaluations within the decision-making processes. The findings are presented and discussed in light of other studies that have addressed this issue. METHODS: Focus group research was conducted with decision makers from a sample of two UK health authorities using the National Health Service Economic Evaluation Database (NHS EED) as a research vehicle to locate and report the findings of relevant economic studies. The study sample was initially invited to respond to questionnaires exploring the usefulness of published economic evaluations in the decision-making process and to outline particular topics that it felt would benefit from similar economic evidence. Following this, a detailed search was undertaken to retrieve structured NHS EED abstracts on these topics such that the usefulness and limitations of economic evaluations to decision making could be determined. RESULTS: Decision makers generally recognized the usefulness and necessity of published economic evaluations in informing their decision-making processes. However, the value of studies was often limited because of the poor generalizability of results, the narrowness of research questions, and the lack of methodological rigor common to many published studies. A total of 237 NHS EED full abstracts were retrieved in the specified areas of interest, which, within specified caveats, were generally found to be useful as decision-making tools. There was a general consensus among decision makers in favor of developing a quality-scoring system for studies, thereby going beyond the critical summaries given in NHS EED. CONCLUSIONS: Decision makers value information on cost-effectiveness as well as effectiveness alone, but methodological improvements are necessary to increase the reliability of economic studies. A quality-scoring system for published studies would be a useful development as a filtering mechanism for decision makers but would raise a number of challenges for health economists.

Attitude of Health Personnel↗