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At least 1,225 records · Page 68Linked to original sources
PubMed1988

Identification of an industrial cohort and verification of its completeness using a complicated system of plant records.

The published literature on occupational mortality studies seldom describes the manner in which cohorts were assembled and efforts made to ensure that all, or nearly all, eligible persons had been enumerated. Researchers must struggle unassisted through a morass of plant records, often not knowing how to utilize important sources of information to the fullest extent. This paper describes the identification of a cohort of over 8,700 foundry workers and the verification of its completeness using existing plant data sources. By understanding the techniques for manipulating data sources in this investigation, researchers may gain insight into the use of materials available to them.

Epidemiologic Methods↗
PubMed1997

Human mortality at very advanced age might be constant.

An attempt was made to identify the course of the mortality rate at the upper tail of human age. The only known data suitable for this purpose were published by Riggs and Millecchia (J.E. Riggs, R.J. Millecchia, Mech. Ageing Dev. 62 (1992) 191-199) and our analysis follows up their results. By means of mathematical elaboration it was proved that these data imply a constant mortality rate (approx. 25% per year) at ages above 113 years for men and above 116 years for women. Indirect arguments supporting the validity of the source data are discussed. Nevertheless, even if the source data are mistaken, we proved they cannot be the product of purely random errors and our results may contribute to the elucidation of the origin of those systematic errors.

Aged↗
PubMed2005

Natalizumab for the treatment of multiple sclerosis and Crohn's disease.

OBJECTIVE: To review the pharmacology, pharmacokinetics, safety, and pivotal clinical trials for natalizumab in the treatment of multiple sclerosis (MS) and inflammatory bowel disease. DATA SOURCES: A PubMed/MEDLINE search was conducted (1966-June 2005), and information was obtained from Iowa Drug Information Services. Additional data sources included meeting abstracts, bibliographies from identified articles, and information from the manufacturer. STUDY SELECTION AND DATA EXTRACTION: Studies and review articles examining natalizumab were evaluated. All published, randomized clinical trials evaluating natalizumab in MS and IBD were included in this review. DATA SYNTHESIS: Natalizumab is the first drug in a new class of agents called selective adhesion molecule inhibitors. It has shown promising results in MS and inflammatory bowel disease and appears superior compared with current therapies in reducing relapse rates. However, 3 recent, confirmed case reports of progressive multifocal leukoencephalopathy (PML) create concern about natalizumab's use in combination with existing therapies or in undefined patient subgroups. Natalizumab was voluntarily withdrawn from the market in March 2005 while the drug's safety is further evaluated. CONCLUSIONS: Although long-term efficacy and safety of natalizumab have not been established, available data indicate that it is a novel drug for patients with MS or inflammatory bowel disease. Analysis of its possible association with PML will determine the risk-benefit evaluation and eventual place in therapy for natalizumab.

Animals↗
PubMed2003

Educational Reform in Athletic Training: A Policy Analysis.

OBJECTIVE: To apply a policy-analysis framework to the athletic training educational reform policy that will be fully implemented by January 2004. DATA SOURCES: Policy analysis is not a specific science. No one framework exists for conducting all policy analyses. I used literature from the education, policy analysis, and athletic training fields as data sources to provide background and to create a framework from which to conduct the policy analysis. DATA SYNTHESIS: Once the policy-analysis framework was selected, I began data synthesis, using several athletic training sources in support of the findings. The tension among the myriad stakeholders in this policy is clear. Although many see the benefits of accreditation, some experience hardships from the imposed policy. CONCLUSIONS/RECOMMENDATIONS: Of the 4 possible alternatives suggested, following the route currently under implementation (Committee on Accreditation of Health Education Programs accreditation) was the most agreeable solution. The goals as stated by the policy makers are attained by the policy. However, issues within the accreditation process itself need to be addressed. Of the many stakeholders in the reform effort, some will see little gain and have many hardships imposed on them. As the policy is implemented, unintended implications will likely arise, as with any new policy. Thus, I recommend that the National Athletic Trainers' Association develop a system dedicated solely to reducing the hardships faced by many of its members as the policy is implemented.

Journal Article↗
PubMed1992

Haemophilus influenzae type B conjugate vaccines.

OBJECTIVE: To review the epidemiology of Haemophilus influenzae type b (Hib) disease, the first Hib vaccine and its limitations, the characteristics and clinical efficacy of the newer conjugate vaccines, and the current recommendations for administration of Hib vaccines. DATA SOURCES: Pertinent literature was identified via a MEDLINE search. Additionally, references cited in published articles were used as data sources. STUDY SELECTION: Studies describing the epidemiology of Hib disease and the efficacy and/or immunogenicity of the Hib vaccines are reviewed. DATA SYNTHESIS: Serious invasive disease secondary to Hib infection causes significant morbidity and mortality in children between the ages of three months and five years. The original Hib vaccine was found to be ineffective in stimulating an adequate immune response in children younger than two years of age. The new Hib conjugate vaccines provide superior efficacy and immunogenicity compared with the original unconjugated vaccine. They stimulate an immune response that is distinctly different from that elicited by the original vaccine. Two vaccine products are currently licensed for use in children as young as two months of age, thus conferring immunity to those children at highest risk for Hib disease. CONCLUSIONS: The new Hib conjugate vaccines provide excellent efficacy and, when used as recommended, may significantly reduce the incidence of invasive Hib disease and its sequelae.

Bacterial Capsules↗
PubMed2004

Low-molecular-weight heparin compared with intravenous unfractionated heparin for treatment of pulmonary embolism: a meta-analysis of randomized, controlled trials.

BACKGROUND: Low-molecular-weight heparin has greatly simplified the management of deep venous thrombosis. However, for patients who present with pulmonary embolism, the role of low-molecular-weight heparin is uncertain and unfractionated heparin remains widely used. PURPOSE: To compare the efficacy and safety of fixed-dose subcutaneous low-molecular-weight heparin with that of dose-adjusted intravenous unfractionated heparin to treat acute pulmonary embolism. DATA SOURCES: The MEDLINE, EMBASE, and Cochrane Library databases were searched up to 1 August 2003. Additional data sources were manual searches of abstract proceedings and personal contact with investigators and pharmaceutical companies. STUDY SELECTION: Randomized trials comparing fixed-dose subcutaneous low-molecular-weight heparin with dose-adjusted intravenous unfractionated heparin for the treatment of nonmassive symptomatic pulmonary embolism or asymptomatic pulmonary embolism in the context of symptomatic deep venous thrombosis. DATA EXTRACTION: Two reviewers independently selected studies and extracted data on study design; quality; and clinical outcomes, including symptomatic venous thromboembolism, death, and major and minor bleeding. Odds ratios for individual outcomes were calculated for each trial and were pooled by using the Mantel-Haenszel method. DATA SYNTHESIS: Fourteen trials involving 2110 patients with pulmonary embolism met the inclusion criteria. Separate outcome data for patients with pulmonary embolism were not available from 2 trials (159 patients), leaving 12 trials for meta-analysis. Compared with unfractionated heparin, low-molecular-weight heparin was associated with a non-statistically significant decrease in recurrent symptomatic venous thromboembolism at the end of treatment (1.4% vs. 2.4%; odds ratio, 0.63 [95% CI, 0.33 to 1.18]) and at 3 months (3.0% vs. 4.4%; odds ratio, 0.68 [CI, 0.42 to 1.09]). Similar estimates were obtained for patients who presented with symptomatic pulmonary embolism (1.7% vs. 2.3%; odds ratio, 0.72 [CI, 0.35 to 1.48]) or asymptomatic pulmonary embolism (1.2% vs. 3.2%; odds ratio, 0.53 [CI, 0.15 to 1.88]). For major bleeding complications, the odds ratio favoring low-molecular-weight heparin (1.3% vs. 2.1%; odds ratio, 0.67 [CI, 0.36 to 1.27]) was also not statistically significant. CONCLUSIONS: Fixed-dose low-molecular-weight heparin treatment appears to be as effective and safe as dose-adjusted intravenous unfractionated heparin for the initial treatment of nonmassive pulmonary embolism.

Hemorrhage↗
PubMed2003

Maternal health outcomes in Europe.

OBJECTIVES: To use PERISTAT data on indicators of maternal mortality and morbidity to explore maternal health outcomes in Europe, and to discuss the implications of variations in the data sources for these indicators. STUDY DESIGN: The PERISTAT feasibility study provides the source for this descriptive study, covering 15 European countries. Maternal mortality ratios are calculated, and data to describe maternal mortality by age, cause of death and mode of delivery are pooled for the countries that provided data. RESULTS: Data presented show an increased risk of maternal death among older mothers and for caesarean sections compared with other modes of delivery, and the three most prevalent causes of maternal deaths reported were embolism, hypertensive diseases of pregnancy, and haemorrhage. CONCLUSIONS: Variations in maternal mortality ratios reflect different data sources with varying levels of ascertainment in addition to differences in the number of maternal deaths. Further development is needed to construct comparable indicators of maternal morbidity.

Adult↗
PubMed2005

Knowledge discovery and system biology in molecular medicine: an application on neurodegenerative diseases.

The possibility to study an organism in terms of system theory has been proposed in the past, but only the advancement of molecular biology techniques allow us to investigate the dynamical properties of a biological system in a more quantitative and rational way than before . These new techniques can gave only the basic level view of an organisms functionality. The comprehension of its dynamical behaviour depends on the possibility to perform a multiple level analysis. Functional genomics has stimulated the interest in the investigation the dynamical behaviour of an organism as a whole. These activities are commonly known as System Biology, and its interests ranges from molecules to organs. One of the more promising applications is the 'disease modeling'. The use of experimental models is a common procedure in pharmacological and clinical researches; today this approach is supported by 'in silico' predictive methods. This investigation can be improved by a combination of experimental and computational tools. The Machine Learning (ML) tools are able to process different heterogeneous data sources, taking into account this peculiarity, they could be fruitfully applied to support a multilevel data processing (molecular, cellular and morphological) that is the prerequisite for the formal model design; these techniques can allow us to extract the knowledge for mathematical model development. The aim of our work is the development and implementation of a system that combines ML and dynamical models simulations. The program is addressed to the virtual analysis of the pathways involved in neurodegenerative diseases. These pathologies are multifactorial diseases and the relevance of the different factors has not yet been well elucidated. This is a very complex task; in order to test the integrative approach our program has been limited to the analysis of the effects of a specific protein, the Cyclin dependent kinase 5 (CDK5) which relies on the induction of neuronal apoptosis. The system has a modular structure centred on a textual knowledge discovery approach. The text mining is the only way to enhance the capability to extract ,from multiple data sources, the information required for the dynamical simulator. The user may access the publically available modules through the following site: http://biocomp.ge.ismac.cnr.it.

Biomedical Research↗
PubMed1994

Projections of health care expenditures as a share of the GDP: actuarial and macroeconomic approaches.

STUDY QUESTION. Can the steady increases in health care expenditures as a share of GDP projected by widely cited actuarial models be rationalized by a macroeconomic model with sensible parameters and specification? DATA SOURCES. National Income and Product Accounts, and Social Security and Health Care Financing Administration are the data sources used in parameters estimates. STUDY DESIGN. Health care expenditures as a share of gross domestic product (GDP) are projected using two methodological approaches--actuarial and macroeconomic--and under various assumptions. The general equilibrium macroeconomic approach has the advantage of allowing an investigation of the causes of growth in the health care sector and its consequences for the overall economy. DATA COLLECTION METHODS. Simulations are used. PRINCIPAL FINDINGS. Both models unanimously project a continued increase in the ratio of health care expenditures to GDP. Under the most conservative assumptions, that is, robust economic growth, improved demographic trends, or a significant moderation in the rate of health care price inflation, the health care sector will consume more than a quarter of national output by 2065. Under other (perhaps more realistic) assumptions, including a continuation of current trends, both approaches predict that health care expenditures will comprise between a third and a half of national output. In the macroeconomic model, the increasing use of capital goods in the health care sector explains the observed rise in relative prices. Moreover, this "capital deepening" implies that a relatively modest fraction of the labor force is employed in health care and that the rest of the economy is increasingly starved for capital, resulting in a declining standard of living.

Actuarial Analysis↗
PubMed2005

Capturing change in a community--university partnership: Si Se Puede! Project.

BACKGROUND: Community health interventions are increasingly employing partnerships combined with multilevel intervention models to achieve their objectives. Resources and methods for project evaluation are often limited to changes in population health status or health behaviors, while broader contextual questions that may illuminate mechanisms for change across ecological levels and project sustainability may not be addressed. CONTEXT: This paper describes a project to prevent and control diabetes in a Latino community and presents practical methods for addressing some challenges to evaluation, using data sources that often may be overlooked. METHODS: A case study method was used to examine approaches to capture data that can help explain changes across ecological levels. An ecological framework was used to organize sources of data. Data sources and findings are related to project timelines and goals. CONSEQUENCES: Although not a direct focus of the original research, substantial changes in community capacity were observed and measured over the course of the five-year project. Documentation on community change was found in routine project reports, logs, the news media, meeting minutes, and community documents. INTERPRETATION: A logical progression of community change across ecological levels became evident. A modest post hoc evaluation was feasible, using data routinely available from project and target community sources. Specific questions for future research on how community change occurs and how such changes may relate to population health and sustainability are suggested.

Chicago↗
PubMed2005

Water quality monitoring: a combined approach to investigate gradients of change in the Great Barrier Reef, Australia.

For the managers of a region as large as the Great Barrier Reef, it is a challenge to develop a cost effective monitoring program, with appropriate temporal and spatial resolution to detect changes in water quality. The current study compares water quality data (phytoplankton abundance and water clarity) from remote sensing with field sampling (continuous underway profiles of water quality and fixed site sampling) at different spatial scales in the Great Barrier Reef north of Mackay (20 degrees S). Five transects (20-30 km long) were conducted from clean oceanic water to the turbid waters adjacent to the mainland. The different data sources demonstrated high correlations when compared on a similar spatial scale (18 fixed sites). However, each data source also contributed unique information that could not be obtained by the other techniques. A combination of remote sensing, underway sampling and fixed stations will deliver the best spatial and temporal monitoring of water quality in the Great Barrier Reef.

Animals↗
PubMed2004

The impact of diabetes on workforce participation: results from a national household sample.

OBJECTIVE: Diabetes is a highly prevalent condition that results in substantial morbidity and premature mortality. We investigated how diabetes-associated mortality, disability, early retirement, and work absenteeism impacts workforce participation. DATA SOURCE: We used the Health and Retirement Study (HRS), a national household sample of adults aged 51-61 in 1992, as a data source. STUDY DESIGN: We conducted cross-sectional analyses on the baseline HRS data, and longitudinal analyses using data from eight years of follow-up. We used two-part regression models to estimate the adjusted impact of diabetes on workforce participation, and then estimated the economic impact of diabetes-related losses in productivity. PRINCIPAL FINDINGS: Diabetes is a significant predictor of lost productivity. The incremental lost income due to diabetes by 1992 was 60.0 billion US dollars over an average diabetes duration of 9.7 years. From 1992 to 2000, diabetes was responsible for 4.4 billion US dollars in lost income due to early retirement, 0.5 billion US dollars due to increased sick days, 31.7 billion US dollars due to disability, and 22.0 US dollars billion in lost income due to premature mortality, for a total of 58.6 billion dollars in lost productivity, or 7.3 billion US dollars per year. CONCLUSIONS: In the U.S. population of adults born between 1931 and 1941, diabetes is associated with a profound negative impact on economic productivity. By 1992, an estimated 60 billion US dollars in lost productivity was associated with diabetes; additional annual losses averaged 7.3 billion US dollars over the next eight years, totaling about 120 billion US dollars by the year 2000. Given the rising prevalence of diabetes, these costs are likely to increase substantially unless countered by better public health or medical interventions.

Chronic Disease↗
PubMed1995

The availability of health care information for consumer use.

This study assesses the current availability of health care cost and quality information at both the state and national levels. More than 130 sources were contacted, including all state commissioners of health and state hospital associations. Eighty-one percent of the responding states report provider-specific information to the public, 73% require providers to submit data to the state, and the department of health or a state health care commission is the data collection entity of 69% of the states. However ambitious or mature some state health care data initiatives have become, the comparative measures of provider performance are generally primitive, the data sources are unreliable in many cases, and the data sources and measures are widely variant across states.

Community Participation↗
PubMed1998

Identifying proteins using matrix-assisted laser desorption/ionization in-source fragmentation data combined with database searching.

Metastable ion decay in matrix-assisted laser desorption/ionization (MALDI) has become a routine method for obtaining primary structures of peptides. Significant fragmentation occurs in the MALDI ion source and can be observed via delayed ion extraction TOF-MS. In-source decay (ISD) can provide C- and N-terminal primary sequence data for even moderate-sized peptides (< 5000 Da). The unique cn series fragmentation that occurs in ISD has been exploited to obtain partial C-terminal sequences for proteins as large as human apotransferrin (75 kDa). Two approaches for combining this ISD MALDI-generated partial sequence information with protein database searching techniques are presented. In one approach, cyanogen bromide is used to cleave relatively large peptide fragments from a sample of human apotransferrin. One of the larger cleavage products (6034.84 Da) was isolated by HPLC and subjected to ISD MALDI analysis. An easily identified cn fragment ion series allowed two noncontiguous segments of the peptide's sequence to be determined (about 55% of the total sequence). This partial sequence information was used to search protein and oligonucleotide sequence databases. In addition to uniquely identifying human apotransferrin in a protein sequence database, an example of the use of this ISD MALDI-determined partial sequence information to search expressed sequence tag databases is presented. Such searches have the potential for rapidly identifying new genes that code for target proteins. An alternate approach for obtaining partial sequence information on proteins is also demonstrated that utilizes ISD MALDI fragmentation of the intact protein to generate partial sequence information. This approach is shown to generate about 5-7% of a protein's sequence, usually near the C-terminus of the protein. Examples of the ISD MALDI fragmentation data obtained from intact (reduced) human apotransferrin and intact (nonreduced) bovine serum albumin (66 kDa) proteins are presented.

Animals↗
PubMed1997

Impact of home care on hospital days: a meta analysis.

OBJECTIVE: To examine the impact of home care on hospital days. DATA SOURCES: Search of automated databases covering 1964-1994 using the key words "home care," "hospice," and "healthcare for the elderly." Home care literature review references also were inspected for additional citations. STUDY SELECTION: Of 412 articles that examined impact on hospital use/cost, those dealing with generic home care that reported hospital admissions/cost and used a comparison group receiving customary care were selected (N = 20). STUDY DESIGN: A meta-analytic analysis used secondary data sources between 1967 and 1992. DATA EXTRACTION: Study characteristics that could have an impact on effect size (i.e., country of origin, study design, disease characteristics of study sample, and length of follow-up) were abstracted and coded to serve as independent variables. Available statistics on hospital days necessary to calculate an effect size were extracted. If necessary information was missing, the authors of the articles were contacted. METHODS: Effect sizes and homogeneity of variance measures were calculated using Dstat software, weighted for sample size. Overall effect sizes were compared by the study characteristics described above. PRINCIPAL FINDINGS: Effect sizes indicate a small to moderate positive impact of home care in reducing hospital days, ranging from 2.5 to 6 days (effect sizes of -.159 and -.379, respectively), depending on the inclusion of a large quasi-experimental study with a large treatment effect. When this outlier was removed from analysis, the effect size for studies that targeted terminally ill patients exclusively was homogeneous across study subcategories; however, the effect size of studies that targeted nonterminal patients was heterogeneous, indicating that unmeasured variables or interactions account for variability. CONCLUSION: Although effect sizes were small to moderate, the consistent pattern of reduced hospital days across a majority of studies suggests for the first time that home care has a significant impact on this costly outcome.

Aged↗
PubMed1997

Chart review. A need for reappraisal.

Imperfections of chart review as a data collection method are detailed, with particular emphasis on the issue of reliability. The authors identify 125 journal articles published between 1991 and 1992 in which the authors' conclusions were based principally on chart review findings and were either clinical or health care epidemiology studies, or quality assessment studies. Eight percent of epidemiology studies and 56% of quality assessment studies presented data on interrater reliability. Forty-four percent of epidemiology studies and 20% of quality assessment studies did not describe the number of chart reviewers involved. Forty-three percent of epidemiology studies and 28% of quality assessment studies used supplementary data sources. The authors conclude that the validity and utility of studies based on chart review would be enhanced by attention to interrater reliability and the use of supplementary data sources.

Data Collection↗
PubMed2004

Population pharmacokinetics I: background, concepts, and models.

OBJECTIVE: To present and emphasize the background, foundations, utility, and conceptual underlying theory of the population pharmacokinetic (PPK) approach with an examination of the advantages when compared with other approaches of pharmacokinetic modeling. DATA SOURCES: Information on PPK was retrieved from a MEDLINE search (1979-June 2002) of literature and a bibliographic review of review articles and books. STUDY SELECTION AND DATA EXTRACTION: All articles identified from data sources were evaluated and relevant information was included in this review. DATA SYNTHESIS: PPK plays a pivotal role in developing dosing strategies for direct patient care and in drug development. PPK is valuable because it targets the patient group that will eventually receive the drug of interest, quantitates pharmacokinetic variability at several levels, and seeks to explain those sources of variability. CONCLUSIONS: PPK models have great utility and the applications are many. They are very different from single-subject pharmacokinetic models and therefore require different approaches to model development.

Humans↗
PubMed1994

Internal validation of Medicare claims data.

The Medicare database is commonly used for epidemiology and health services research, but validation of its data by chart review or questionnaire may be difficult and expensive. Since hospital and physician bills are independent in Medicare, however, these two data sources can be used to supplement and corroborate each other. This "internal validation" is illustrated here for hip fracture and prostatectomy. Agreement of the hospital and physician data streams regarding site of hip fracture (neck vs other), treatment of hip fracture (internal fixation vs arthroplasty), and type of prostatectomy (transurethral resection of prostate, open, or radical) was excellent, with percentage of agreement generally between 89% and 99%, and kappa statistics typically between 0.74 and 0.95. When validation with outside data sources is not readily available, such internal validation of Medicare data may be valuable.

Abstracting and Indexing↗