Showing papers by "Christopher J L Murray published in 2003"

WHO Framework Convention on Tobacco Control: development of an evidence based global public health treaty

Abstract: Many health problems require international action, but getting governments to agree on strategies for prevention or treatment is difficult. By making use of scientific evidence on the effects of tobacco, the member states of WHO have negotiated their first global health treaty. If the treaty can be implemented effectively, it could act as a possible model for tackling other health issues When Dr Gro Harlem Brundtland became director general of the World Health Organization in 1998, she clearly stated that the tobacco epidemic should be tackled by an international collective action and that WHO should take a leadership role.1 In 1999, WHO started work on the WHO Framework Convention on Tobacco Control, which was endorsed by member states on 21 May 2003. It is the first time WHO has used its constitutional authority in global public health to develop a legal instrument aimed at improving population health. The initiation and negotiation of the framework convention was based strongly on the accumulation of scientific evidence.2 We review the development and scientific basis of the convention and discuss its implications and the potential of international collective action against threats to global public health. The structural basis for framework conventions is to use an incremental process in making law. It begins with a framework convention that establishes a general consensus on the relevant facts and the system of governance for an issue. This is followed by the development of more specific commitments and institutional arrangements in subsequent protocols.3 However, depending on the political will, framework conventions can also include quite specific provisions. In the case of the WHO Framework Convention on Tobacco Control, the powerful political momentum behind the treaty has ensured that several detailed provisions have been incorporated into the final text.4 The framework convention is the first …

Enhancing the Validity and Cross-cultural Comparability of Measurement in Survey Research

Abstract: We address two long-standing survey research problems: measuring complicated concepts, such as political freedom and efficacy, that researchers define best with reference to examples; and what to do when respondents interpret identical questions in different ways. Scholars have long addressed these problems with approaches to reduce incomparability, such as writing more concrete questions—with uneven success. Our alternative is to measure directly response category incomparability and to correct for it. We measure incomparability via respondents’ assessments, on the same scale as the self-assessments to be corrected, of hypothetical individuals described in short vignettes. Because the actual (but not necessarily reported) levels of the vignettes are invariant over respondents, variability in vignette answers reveals incomparability. Our corrections require either simple recodes or a statistical model designed to save survey administration costs. With analysis, simulations, and cross-national surveys, we show how response incomparability can drastically mislead survey researchers and how our approach can alleviate this problem.

Comparative quantification of health risks: Conceptual framework and methodological issues

Abstract: Reliable and comparable analysis of risks to health is key for preventing disease and injury. Causal attribution of morbidity and mortality to risk factors has traditionally been conducted in the context of methodological traditions of individual risk factors, often in a limited number of settings, restricting comparability.In this paper, we discuss the conceptual and methodological issues for quantifying the population health effects of individual or groups of risk factors in various levels of causality using knowledge from different scientific disciplines. The issues include: comparing the burden of disease due to the observed exposure distribution in a population with the burden from a hypothetical distribution or series of distributions, rather than a single reference level such as non-exposed; considering the multiple stages in the causal network of interactions among risk factor(s) and disease outcome to allow making inferences about some combinations of risk factors for which epidemiological studies have not been conducted, including the joint effects of multiple risk factors; calculating the health loss due to risk factor(s) as a time-indexed "stream" of disease burden due to a time-indexed "stream" of exposure, including consideration of discounting; and the sources of uncertainty.

A generic model for the assessment of disease epidemiology: the computational basis of DisMod II

Abstract: Epidemiology as an empirical science has developed sophisticated methods to measure the causes and patterns of disease in populations Nevertheless, for many diseases in many countries only partial data are available When the partial data are insufficient, but data collection is not an option, it is possible to supplement the data by exploiting the causal relations between the various variables that describe a disease process We present a simple generic disease model with incidence, one prevalent state, and case fatality and remission We derive a set of equations that describes this disease process and allows calculation of the complete epidemiology of a disease given a minimum of three input variables We give the example of asthma with age-specific prevalence, remission, and mortality as inputs Outputs are incidence and case fatality, among others The set of equations is embedded in a software package called 'DisMod II', which is made available to the public domain by the World Health Organization

Population health metrics: crucial inputs to the development of evidence for health policy

Abstract: Valid, reliable and comparable measures of the health states of individuals and of the health status of populations are critical components of the evidence base for health policy. We need to develop population health measurement strategies that coherently address the relationships between epidemiological measures (such as risk exposures, incidence, and mortality rates) and multi-domain measures of population health status, while ensuring validity and cross-population comparability. Studies reporting on descriptive epidemiology of major diseases, injuries and risk factors, and on the measurement of health at the population level – either for monitoring trends in health levels or inequalities or for measuring broad outcomes of health systems and social interventions – are not well-represented in traditional epidemiology journals, which tend to concentrate on causal studies and on quasi-experimental design. In particular, key methodological issues relating to the clear conceptualisation of, and the validity and comparability of measures of population health are currently not addressed coherently by any discipline, and cross-disciplinary debate is fragmented and often conducted in mutually incomprehensible language or paradigms. Population health measurement potentially bridges a range of currently disjoint fields of inquiry relating to health: biology, demography, epidemiology, health economics, and broader social science disciplines relevant to assessment of health determinants, health state valuations and health inequalities. This new journal will focus on the importance of a population based approach to measurement as a way to characterize the complexity of people's health, the diseases and risks that affect it, its distribution, and its valuation, and will attempt to provide a forum for innovative work and debate that bridge the many fields of inquiry relevant to population health in order to contribute to the development of valid and comparable methods for the measurement of population health and its determinants.

Modified logit life table system: Principles, empirical validation, and application

Abstract: Despite its widespread use, the Coale-Demeny model life table system does not capture the extensive variation in age-specific mortality patterns observed in contemporary populations, particularly those of the countries of Eastern Europe and populations affected by HIV/AIDS. Although relational mortality models, such as the Brass logit system, can identify these variations, these models show systematic bias in their predictive ability as mortality levels depart from the standard. We propose a modification of the two-parameter Brass relational model. The modified model incorporates two additional age-specific correction factors (gamma(x), and theta(x)) based on mortality levels among children and adults, relative to the standard. Tests of predictive validity show deviations in age-specific mortality rates predicted by the proposed system to be 30-50 per cent lower than those predicted by the Coale-Demeny system and 15-40 per cent lower than those predicted using the original Brass system. The modified logit system is a two-parameter system, parameterized using values of l(5) and l(60).

Correction: Global and regional estimates of cancer mortality and incidence by site: II. results for the global burden of disease 2000 (vol 2, pg 37, 2002)

Abstract: After the publication of this work [1], we noticed the typographical errors in Tables 8, 9, 16, and 17: there were inconsistencies between the ranking of cancer mortality and incidence and their corresponding figures. Here we briefly present the results along with the revisions of the relevant tables since the ranking was corrected while the figures remained the same as the original.

Infant mortality rate as an indicator of population health. Commentaries

Abstract: Background: The infant mortality rate (IMR) has been criticised as a measure of population health because it is narrowly based and likely to focus the attention of health policy on a small part of the population to the exclusion of the rest. More comprehensive measures such as disability adjusted life expectancy (DALE) have come into favour as alternatives. These more comprehensive measures of population health, however, are more complex, and for resource poor countries, this added burden could mean diverting funds from much needed programmes. Unfortunately, the conjecture, that DALE is a better measure of population health than IMR, has not been empirically tested. Methods: IMR and DALE data for 1997 were obtained from the World Bank and the World Health Organisation, respectively, for 180 countries. Findings: There is a strong (generally) linear association between DALE and IMR (r=0.91) Countries with low DALE tend to have a high IMR. The countries with the lowest IMRs had DALEs above that predicted by the regression line. Interpretation: There is little evidence that the use of IMR as a measure of population health has a negative impact on older groups in the population. IMR remains an important indicator of health for whole populations, reflecting the intuition that structural factors affecting the health of entire populations have an impact on the mortality rate of infants. For countries with limited resources that require an easily calculated, pithy measure of population health, IMR may remain a suitable choice.

Alternative summary measures of average population health

Abstract: Decision-makers in countries around the world face a series of common problems as they aim to make appropriate choices to improve the performance of their health systems. With eight per cent of the world’s economic output invested in health systems, the way these systems are organized to collect resources and transform them into services for people in need can profoundly influence health outcomes for populations. Yet the scientific evidence-base to inform critical health system decisions is much weaker than the evidence-base to inform individual clinical decisions. Policy advice on health system development has, until recently, been based on case-studies and, sometimes, ideology. Case-studies can be useful partly because health systems and cultures all differ in many ways. There is a great deal of knowledge, however, to be gained from the experiences of groups of countries taken together, learning from common experience. This volume reports on a large body of work led by the World Health Organization that is intended to strengthen the foundations for evidence-based policies aimed at health systems development. This has included work to develop a common conceptual framework for health systems performance assessment, to encourage the development of tools to measure its components, and to collaborate with countries in applying these tools to measure and then to improve health systems performance. It began with the enunciation of a framework that specified a parsimonious set of key goals to which health systems contribute, and the first set of figures on goal attainment and health system efficiency in countries that were Members of the Organization was published in The World Health Report 2000. This book provides a uniquely comprehensive exploration of many different facets of health systems performance assessment. It will be relevant for researchers, students and decision-makers seeking a more detailed understanding of concepts, methods and the latest empirical findings. While most authors in this volume take a global perspective, the findings have important implications for the development of national performance frameworks and the creation of a culture of accountability.

Infant mortality is not an adequate summary measure of population health

Abstract: Measuring the quantity of interest The World Health Organisation (WHO) annually reports infant mortality rates (IMR), child mortality rates, adult mortality rates, average life expectancies, and healthy life expectancies for all 191 member states.1,2 IMR correlates highly with HALE across these 191 member states in 2000 ( r =0.93). Reidpath and Allotey argue that IMR is an acceptable proxy measure of population health because of this high correlation.3 Inspection of the country specific estimates of HALE and IMR reveals that, despite the high correlation, there are substantial variations both in adult mortality and in the average loss of full health at any given level of IMR. In the nine countries with an IMR in the range of 6–7 per 1000, for example, there is a range of 71 to 80 in life expectancy at birth and a range of 10% to 15% in the proportion of total life expectancy …

Introduction of article-processing charges for Population Health Metrics

Abstract: Population Health Metrics is an open-access online electronic journal published by BioMed Central – it is universally and freely available online to everyone, its authors retain copyright, and it is archived in at least one internationally recognised free repository. To fund this, from November 1 2003, authors of articles accepted for publication will be asked to pay an article-processing charge of US$500. This editorial outlines the reasons for the introduction of article-processing charges and the way in which this policy will work.