15 research outputs found
Cause-specific mortality time series analysis: a general method to detect and correct for abrupt data production changes
<p>Abstract</p> <p>Background</p> <p>Monitoring the time course of mortality by cause is a key public health issue. However, several mortality data production changes may affect cause-specific time trends, thus altering the interpretation. This paper proposes a statistical method that detects abrupt changes ("jumps") and estimates correction factors that may be used for further analysis.</p> <p>Methods</p> <p>The method was applied to a subset of the AMIEHS (Avoidable Mortality in the European Union, toward better Indicators for the Effectiveness of Health Systems) project mortality database and considered for six European countries and 13 selected causes of deaths. For each country and cause of death, an automated jump detection method called Polydect was applied to the log mortality rate time series. The plausibility of a data production change associated with each detected jump was evaluated through literature search or feedback obtained from the national data producers.</p> <p>For each plausible jump position, the statistical significance of the between-age and between-gender jump amplitude heterogeneity was evaluated by means of a generalized additive regression model, and correction factors were deduced from the results.</p> <p>Results</p> <p>Forty-nine jumps were detected by the Polydect method from 1970 to 2005. Most of the detected jumps were found to be plausible. The age- and gender-specific amplitudes of the jumps were estimated when they were statistically heterogeneous, and they showed greater by-age heterogeneity than by-gender heterogeneity.</p> <p>Conclusion</p> <p>The method presented in this paper was successfully applied to a large set of causes of death and countries. The method appears to be an alternative to bridge coding methods when the latter are not systematically implemented because they are time- and resource-consuming.</p
LISS panel > Left- and right-handedness
This questionnaire examines finger length and the extent to which people are left- or right-handed
Rule of law and legal epistemology
In the positivistic conception of law, sources of law (statute, precedent) are strictly distinguished from other legal materials such as doctrine. Courts as well as academia are, however, beginning to recognise the legal relevance of doctrine and case law of lower courts. This acceptance of such epistemic sources is justified within the rule of law if we recognise that courts and legislators do not create law in a vacuum, but rather build on a prior body of legal knowledge. This is relevant to legal argumentation and legal methodology, as it explicates that we have to take epistemic sources into account. This approach is supported by the recent epistemological recognition of testimony as source of knowledge. The epistemological approach to law offers an explanation to the recognition of precedents as source of law, and the authority of non-binding texts, thereby being suitable to a multi-level legal order where authority is more fluid than in traditional positivism
Crystal structures of TAFI elucidate the inactivation mechanism of activated TAFI: a novel mechanism for enzyme autoregulation
Thrombin-activatable fibrinolysis inhibitor (TAFI) is a pro-metallocarboxypeptidase that can be proteolytically activated (TAFIa). TAFIa is unique among carboxypeptidases in that it spontaneously inactivates with a short half-life, a property that is crucial for its role in controlling blood clot lysis. We studied the intrinsic instability of TAFIa by solving crystal structures of TAFI, a TAFI inhibitor (GEMSA) complex and a quadruple TAFI mutant (70-fold more stable active enzyme). The crystal structures show that TAFIa stability is directly related to the dynamics of a 55-residue segment (residues 296-350) that includes residues of the active site wall. Dynamics of this flap are markedly reduced by the inhibitor GEMSA, a known stabilizer of TAFIa, and stabilizing mutations. Our data provide the structural basis for a model of TAFI auto-regulation: in zymogen TAFI the dynamic flap is stabilized by interactions with the activation peptide. Release of the activation peptide increases dynamic flap mobility and in time this leads to conformational changes that disrupt the catalytic site and expose a cryptic thrombin-cleavage site present at Arg302. This represents a novel mechanism of enzyme control that enables TAFI to regulate its activity in plasma in the absence of specific inhibitor
Using 'amenable mortality' as indicator of healthcare effectiveness in international comparisons: results of a validation study.
BACKGROUND AND STUDY AIMS: There is widespread consensus on the need for better indicators of the effectiveness of healthcare. We carried out an analysis of the validity of amenable mortality as an indicator of the effectiveness of healthcare, focusing on the potential use in routine surveillance systems of between-country variations in rates of mortality. We assessed whether the introduction of specific healthcare innovations coincided with declines in mortality from potentially amenable causes in seven European countries. In this paper, we summarise the main results of this study and illustrate them for four conditions. DATA AND METHODS: We identified 14 conditions for which considerable declines in mortality have been observed and for which there is reasonable evidence in the literature of the effectiveness of healthcare interventions to lower mortality. We determined the time at which these interventions were introduced and assessed whether the innovations coincided with favourable changes in the mortality trends from these conditions, measured using Poisson linear spline regression. All the evidence was then presented to a Delphi panel. MAIN RESULTS: The timing of innovation and favourable change in mortality trends coincided for only a few conditions. Other reasons for mortality decline are likely to include diffusion and improved quality of interventions and in incidence of diseases and their risk factors, but there is insufficient evidence to differentiate these at present. For most conditions, a Delphi panel could not reach consensus on the role of current mortality levels as measures of effectiveness of healthcare. DISCUSSION AND CONCLUSIONS: Improvements in healthcare probably lowered mortality from many of the conditions that we studied but occurred in a much more diffuse way than we assumed in the study design. Quantification of the contribution of healthcare to mortality requires adequate data on timing of innovation and trends in diffusion and quality and in incidence of disease, none of which are currently available. Given these gaps in knowledge, between-country differences in levels of mortality from amenable conditions should not be used for routine surveillance of healthcare performance. The timing and pace of mortality decline from amenable conditions may provide better indicators of healthcare performance
Innovations in health care and mortality trends from five cancers in seven European countries between 1970 and 2005.
OBJECTIVES: Although the contribution of health care to survival from cancer has been studied extensively, much less is known about its contribution to population health. We examine how medical innovations have influenced trends in cause-specific mortality at the national level. METHODS: Based on literature reviews, we selected six innovations with proven effectiveness against cervical cancer, Hodgkin's disease, breast cancer, testicular cancer, and leukaemia. With data on the timing of innovations and cause-specific mortality (1970-2005) from seven European countries we identified associations between innovations and favourable changes in mortality. RESULTS: For none of the five specific cancers, sufficient evidence for an association between introduction of innovations and a positive change in mortality could be found. The highest association was found between the introduction of Tamoxifen and breast cancer mortality. CONCLUSIONS: The lack of evidence of health care effectiveness may be due to gradual improvements in treatment, to effects limited to certain age groups or cancer subtypes, and to contemporaneous changes in cancer incidence. Research on the impact of health care innovations on population health is limited by unreliable data on their introduction
Using âamenable mortalityâ as indicator of healthcare effectiveness in international comparisons: results of a validation study
Using 'amenable mortality' as indicator of healthcare effectiveness in international comparisons: Results of a validation study
Background and study aims There is widespread
consensus on the need for better indicators of the
effectiveness of healthcare. We carried out an analysis of
the validity of amenable mortality as an indicator of the
effectiveness of healthcare, focusing on the potential use
in routine surveillance systems of between-country
variations in rates of mortality. We assessed whether the
introduction of specific healthcare innovations coincided
with declines in mortality from potentially amenable
causes in seven European countries. In this paper, we
summarise the main results of this study and illustrate
them for four conditions.
Data and methods We identified 14 conditions for
which considerable declines in mortality have been
observed and for which there is reasonable evidence in
the literature of the effectiveness of healthcare
interventions to lower mortality. We determined the time
at which these interventions were introduced and
assessed whether the innovations coincided with
favourable changes in the mortality trends from these
conditions, measured using Poisson linear spline
regression. All the evidence was then presented to
a Delphi panel.
Main results The timing of innovation and favourable
change in mortality trends coincided for only a few
conditions. Other reasons for mortality decline are likely
to include diffusion and improved quality of interventions
and in incidence of diseases and their risk factors, but
there is insufficient evidence to differentiate these at
present. For most conditions, a Delphi panel could not
reach consensus on the role of current mortality levels as
measures of effectiveness of healthcare.
Discussion and conclusions Improvements in
healthcare probably lowered mortality from many of th