26 research outputs found
Building a data sharing model for global genomic research
Data sharing models designed to facilitate global business provide insights for improving transborder genomic data sharing. We argue that a flexible, externally endorsed, multilateral arrangement , combined with an objective third-party assurance mechanism, can effectively balance privacy with the need to share genomic data globally
Mortality in Dutch hospitals: Trends in time, place and cause of death after admission for myocardial infarction and stroke. An observational study
<p>Abstract</p> <p>Background</p> <p>Patterns in time, place and cause of death can have an important impact on calculated hospital mortality rates. Objective is to quantify these patterns following myocardial infarction and stroke admissions in Dutch hospitals during the period 1996â2003, and to compare trends in the commonly used 30-day in-hospital mortality rates with other types of mortality rates which use more extensive follow-up in time and place of death.</p> <p>Methods</p> <p>Discharge data for all Dutch admissions for index conditions (1996â2003) were linked to the death certification registry. Then, mortality rates within the first 30, 90 and 365 days following admissions were analyzed for deaths occurring within and outside hospitals.</p> <p>Results</p> <p>Most deaths within a year after admission occurred within 30 days (60â70%). No significant trends in this distribution of deaths over time were observed. Significant trends in the distribution over place of death were observed for both conditions. For myocardial infarction, the proportion of deaths after transfer to another hospital has doubled from 1996â2003. For stroke a significant rise of the proportion of deaths outside hospital was found. For MI the proportion of deaths attributed to a circulatory disease has significantly fallen ovtime. Seven types of hospital mortality indicators, different in scope and observation period, all show a drop of hospital mortality for both MI and stroke over the period 1996â2003. For stroke the observed absolute reduction in death rate increases for the first year after admission, for MI the observed drop in 365-day overall mortality almost equals the observed drop in 30-day in hospital mortality over 1996â2003.</p> <p>Conclusion</p> <p>Changes in the timing, place and causes of death following admissions for myocardial infarction and stroke have important implications for the definitions of in-hospital and post-admission mortality rates as measures of hospital performance. Although necessary for understanding mortality patterns over time, including within mortality rates deaths which occur outside hospitals and after longer periods following index admissions remain debatable and may not reflect actual hospital performance but probably mirrors transfer, efficiency, and other health care policies.</p
The re-identification risk of Canadians from longitudinal demographics
<p>Abstract</p> <p>Background</p> <p>The public is less willing to allow their personal health information to be disclosed for research purposes if they do not trust researchers and how researchers manage their data. However, the public is more comfortable with their data being used for research if the risk of re-identification is low. There are few studies on the risk of re-identification of Canadians from their basic demographics, and no studies on their risk from their longitudinal data. Our objective was to estimate the risk of re-identification from the basic cross-sectional and longitudinal demographics of Canadians.</p> <p>Methods</p> <p>Uniqueness is a common measure of re-identification risk. Demographic data on a 25% random sample of the population of Montreal were analyzed to estimate population uniqueness on postal code, date of birth, and gender as well as their generalizations, for periods ranging from 1 year to 11 years.</p> <p>Results</p> <p>Almost 98% of the population was unique on full postal code, date of birth and gender: these three variables are effectively a unique identifier for Montrealers. Uniqueness increased for longitudinal data. Considerable generalization was required to reach acceptably low uniqueness levels, especially for longitudinal data. Detailed guidelines and disclosure policies on how to ensure that the re-identification risk is low are provided.</p> <p>Conclusions</p> <p>A large percentage of Montreal residents are unique on basic demographics. For non-longitudinal data sets, the three character postal code, gender, and month/year of birth represent sufficiently low re-identification risk. Data custodians need to generalize their demographic information further for longitudinal data sets.</p
Physician privacy concerns when disclosing patient data for public health purposes during a pandemic influenza outbreak
Background: Privacy concerns by providers have been a barrier to disclosing patient information for public health\ud
purposes. This is the case even for mandated notifiable disease reporting. In the context of a pandemic it has been\ud
argued that the public good should supersede an individualâs right to privacy. The precise nature of these provider\ud
privacy concerns, and whether they are diluted in the context of a pandemic are not known. Our objective was to\ud
understand the privacy barriers which could potentially influence family physiciansâ reporting of patient-level\ud
surveillance data to public health agencies during the Fall 2009 pandemic H1N1 influenza outbreak.\ud
Methods: Thirty seven family doctors participated in a series of five focus groups between October 29-31 2009.\ud
They also completed a survey about the data they were willing to disclose to public health units. Descriptive\ud
statistics were used to summarize the amount of patient detail the participants were willing to disclose, factors that\ud
would facilitate data disclosure, and the consensus on those factors. The analysis of the qualitative data was based\ud
on grounded theory.\ud
Results: The family doctors were reluctant to disclose patient data to public health units. This was due to concerns\ud
about the extent to which public health agencies are dependable to protect health information (trusting beliefs),\ud
and the possibility of loss due to disclosing health information (risk beliefs). We identified six specific actions that\ud
public health units can take which would affect these beliefs, and potentially increase the willingness to disclose\ud
patient information for public health purposes.\ud
Conclusions: The uncertainty surrounding a pandemic of a new strain of influenza has not changed the privacy\ud
concerns of physicians about disclosing patient data. It is important to address these concerns to ensure reliable\ud
reporting during future outbreaks.University of Ottawa Open Access Author Fun
Experimental investigation of the fatigue characteristics of silver loop interconnectors
Thin silver interconnectors are used in the space communication industry to ensure electrical conductivity between neighbouring electronic modules. In order to accommodate a large range of strains, these interconnectors are manufactured with a stress-relief loop shape. The main goal of this thesis is the study of the experimental aspects of the low cycle fatigue of these interconnectors.The development of an in-situ automated fatigue testing procedure is described in detail. This procedure, which involves a miniature cycling device situated inside the vacuum chamber of a scanning electron microscope (SEM), was applied to several pure silver interconnectors with different loop heights. The use of the SEM enables observation, at high magnification, of the interconnector while it is being tested. A new parameter, , which includes the interconnector's geometrical characteristics, is introduced. The experimental results show that the fatigue life of interconnectors can be predicted from a knowledge of . A new approach to the measurement of strain at the top of interconnectors' loop is also proposed. The technique requires the use of the SEM and the deposition of 2 m spheres as surface markers.In addition to the experimental technique, a three-dimensional linear finite element analysis of the interconnectors is performed. This analysis is carried out using more than 2,000 elements and three different materials. Strain evaluations are found to be in good agreement with those experimentally obtained
Passage Retrieval in Log Files: An Approach Based on Query Enrichment
Abstract. The question answering systems are considered the next generation of search engines. This paper focuses on the first step of this process, which is to search for relevant passages containing answers. Passage Retrieval, can be difficult because of the complexity of data, log files in our case. Our contribution is based on the enrichment of queries by using a learning method and a novel term weighting function. This original term weighting function, used within the enrichment process, aims to assign a weight to terms according to their relatedness to the context of answers. Experiments conducted on real data show that our protocol of primitive query enrichment make it possible to retrieve relevant passages.