Search

OBJECTIVE: Administrative health databases are increasingly used to conduct population-based health research and surveillance; this has resulted in a corresponding growth in studies about their quality. Our objective was to describe the characteristics of published Canadian studies about administrative health database quality. METHODS: PubMed, Scopus, and Google Advanced were searched, along with websites of relevant organizations. English-language studies that evaluated the quality of one or more Canadian administrative health databases between 2004 and 2014 were selected for inclusion. Extracted information included data quality concepts and measures, year and type of publication, type of database, and geographic origin. SYNTHESIS: More than 3,000 publications were identified from the search. Twelve reports and 144 peer-reviewed papers were included. The majority (53.5%) of peer-review publications used databases from Ontario and Alberta, while 67% of the non-peer-review publications used data from multiple provinces/territories. Almost all peer-reviewed papers (97.2%) were validation studies. Hospital discharge abstracts and physician billing claims were the most frequently validated databases. Approximately half of the publications (53.0%) validated case definitions and 37.7% focused on a chronic physical health condition. CONCLUSION: Gaps in the Canadian administrative data quality literature include a limited number of studies evaluating data from the Maritimes and across multiple jurisdictions, newer data sources, validating methods for identifying individuals with mental illness, and assessing the completeness and serviceability of the data. Data quality studies can aid researchers to understand the strengths and limitations of the data. KEY WORDS: Data linkage; administrative health database; diagnosis codes; validation studies; review study OBJECTIF : On utilise de plus en plus les bases de donnees administratives sur la sante dans la recherche et la surveillance populationnelles en sante; le nombre d'etudes sur la qualite de ces bases de donnees croit lui aussi. Nous avons cherche a decrire les caracteristiques des etudes canadiennes publiees portant sur la qualite des bases de donnees administratives sur la sante. METHODE : Nous avons interroge PubMed, Scopus et Google Advanced, ainsi que les sites Web d'organismes pertinents. Nous avons inclus les etudes en anglais evaluant la qualite d'une ou de plusieurs bases de donnees administratives canadiennes sur la sante entre 2004 et 2014. Nous en avons extrait : les concepts et les indicateurs de la qualite des donnees; l'annee et le type de publication; le type de base de donnees; et l'origine geographique. SYNTHESE : La recherche a permis de repertorier plus de 3 000 publications. Douze rapports et 144 communications evaluees par des pairs ont ete inclus. La majorite (53,5%) des publications a comite de lecture utilisaient des bases de donnees de l'Ontario et de l'Alberta, tandis que 67% des publications sans comite de lecture utilisaient des donnees de plusieurs provinces ou territoires. Presque toutes les communications evaluees par des pairs (97,2%) etaient des etudes de validation. Les registres des sorties des hopitaux et les demandes de paiement des medecins etaient les bases de donnees les plus frequemment validees. Environ la moitie des publications (53,0%) validaient des definitions de cas et 37,7% portaient sur un probleme de sante physique chronique. CONCLUSION : La documentation sur la qualite des donnees administratives canadiennes comporte des lacunes, car un nombre limite d'etudes evaluent les donnees des provinces maritimes ou de plusieurs provinces ou territoires; evaluent les nouvelles sources de donnees; valident les methodes d'identification des personnes atteintes de maladies mentales; et evaluent l'exhaustivite et la fonctionnalite des donnees. Les etudes sur la qualite des donnees peuvent aider les chercheurs a comprendre les forces et les contraintes des donnees. MOTS CLES : maillage de donnees; base de donnees administratives sur la sante; codes de diagnostic; etudes de validation; etude de synthese La traduction du resume se trouve a la fin de l'article. Can J Public Health 2016;107(1):e56-e61 doi: 10.17269/CJPH.107.5244, Canada has one of the richest collections worldwide of electronic health databases, including administrative health databases, clinical registries, electronic medical records, and health surveys. (1,2) The number of studies that [...]

International Index to Music Periodicals Full Text. ProQuest LLC, 2010. http://iimpft.chadwyck.com (Accessed August 2009 to March 2010). [Requires a Web browser, an Internet connection, Adobe Reader plug-in to view PDF [...]

Electrospray ionization (ESI)-time-of-flight (TOF) MS enables searching a wide number of pharmaco/toxicologically relevant compounds (PTRC) in biosamples. However, the number of identifiable PTRC depends on extension of reference database of chemical formulas/ compound names. Previous approaches proposed in-house or commercial databases with limitations either in PTRC number or content (e.g., few metabolites, presence of non-PTRC). In the frame of development of a ESI-TOF PTRC screening procedure, a subset of PubChem Compound as reference database is proposed. Features of this database (approximately 50 500 compounds) are illustrated, and its performance evaluated through analysis by capillary electrophoresis (CE)-ESI-TOF of hair/blood/ urine collected from subjects under treatment with known drugs or by comparison with reference standards. The database is rich in parent compounds of pharmaceutical and illicit drugs, pesticides, and poisons and contains many metabolites (including about 6 000 phase I metabolites and 180 glucuronides) and related substances (e.g., impurities, esters). The average number of hits with identical chemical formula is 1.82 [+ or -] 2.27 (median = 1, range 1-39). Minor deficiencies, redundancies, and errors have been detected that do not limit the potential of the database in identifying unknown PTRC. The database allows a much broader search for PTRC than other commercial/in-house databases of chemical formulas/ compound names previously proposed. However, the probability that a search retrieves different PTRC having identical chemical formula is higher than with smaller databases, and additional information (anamnestic/ circumstantial data, concomitant presence of parent drug and metabolite, selective sample preparation, liquid chromatographic retention, and CE migration behavior) must be used in order to focus the search more tightly.

Publications in scientific journals contain a considerable fraction of our scientific knowledge. Analyzing data from publication databases helps us understand how this knowledge is obtained and how it changes over time. In this study, we present a mathematical model for the temporal dynamics of data on the scientific content of publications. Our data set consists of references to thousands of genes in the >15 million publications listed in PubMed. We show that the observed dynamics may result from a simple process: Researchers predominantly publish on genes that already appear in many publications. This might be a rewarding strategy for researchers, because there is a positive correlation between the frequency of a gene in scientific publications and the journal impact of the publications. By comparing the empirical data with model predictions, we are able to detect unusual publication patterns that often correspond to major achievements in the field. We identify interactions between yeast genes from PubMed and show that the frequency differences of genes in publications lead to a biased picture of the resulting interaction network. cultural information | life sciences | mathematical model | text mining

The Aircraft Accident Statistics and Knowledge (AASK) database is a repository of passenger accounts from survivable aviation accidents/incidents compiled from interview data collected by agencies such as the US NTSB. Its main purpose is to store observational and anecdotal data from the actual interviews of the occupants involved in aircraft accidents. The database has wide application to aviation safety analysis, being a source of factual data regarding the evacuation process. It also plays a significant role in the development of the airEXODUS aircraft evacuation model, where insight into how people actually behave during evacuation from survivable aircraft crashes is required. This paper describes the latest version of the database (Version 4.0) and includes some analysis of passenger behavior during actual accidents/incidents.

Techniques for efficiently executing multiquery workloads from data and computation-intensive applications in parallel and/or distributed computing environments common implementation for the queries under study was provided according to the database optimization framework and deployed on the top of three distinct experimental configurations are investigated.

Byline: Timothy R. Anderson (1), Paul Rouse (2), Rafael Borja (1), Ivan Patricio Hernandez (1), Fabricio Tobar (1), Liono Setiowijoso (1) Keywords: data envelopment analysis; datasets; databases Abstract: Website databases provide the opportunity to fundamentally change the way research and knowledge are advanced and disseminated. This paper describes a website, http://www.etm.pdx.edu/dea/dataset/, focused on Data Envelopment Analysis and DEA researchers. Author Affiliation: (1) Department of Engineering &amp Technology Management, Portland State University, Portland, OR, 97207-0751, United States of America (2) Department of Accounting &amp Finance, The University of Auckland, Private Bag 92019, Auckland, New Zealand Article History: Registration Date: 03/10/2004

Objective: To suggest improvements to 13 data sets and systems that collect information about juvenile victimization in United States. Method: The suggestions were gathered from a variety of sources, including data system users and administrators, as well as a special meeting convened on the topic by the National Consortium on Children, Families and the Law in Washington, DC (December 2000). Results: Key areas of improvement were identified for each of 13 US data systems and possible solutions were identified. Conclusions: This paper suggests three broad categories of improvements that apply to a number of data systems. First, data systems could expand the coverage of the systems to include more jurisdictions or other segments of the population. Second, in order to be more comprehensive and specific to child victimization, the systems need to create more specific data items, questions, or response categories. Finally, the data systems need to be modified to provide continuity and interrelationships among systems, either by using uniform definitions, or integrating data systems to facilitate the tracking of children across systems. Keywords: Victimization; Statistics; Juvenile; Data system

Novel database applications, such as multimedia, data mining, e-commerce, and many others, make intensive use of similarity queries in order to retrieve the objects that better fit a user request. Since the effectiveness of such queries improves when the user is allowed to personalize the similarity criterion according to which database objects are evaluated and ranked, the development of access methods able to efficiently support user-defined similarity queries becomes a basic requirement. In this article we introduce the first index structure, called the QIC-M-tree, that can process user-defined queries in generic metric spaces, that is, where the only information about indexed objects is their relative distances. The QIC-M-tree is a metric access method that can deal with several distinct distances at a time: (1) a query (user-defined) distance, (2) an index distance (used to build the tree), and (3) a comparison (approximate) distance (used to quickly discard from the search uninteresting parts of the tree). We develop an analytical cost model that accurately characterizes the performance of the QIC-M-tree and validate such model through extensive experimentation on real metric data sets. In particular, our analysis is able to predict the best evaluation strategy (i.e., which distances to use) under a variety of configurations, by properly taking into account relevant factors such as the distribution of distances, the cost of computing distances, and the actual index structure. We also prove that the overall saving in CPU search costs when using an approximate distance can be estimated by using information on the data set only (thus such measure is independent of the underlying access method) and show that performance results are closely related to a novel "indexing" error measure. Categories and Subject Descriptors: E.1 [Data]: Data Structures--trees; H.2.2 [Database Management]: Physical Design--access methods; H.2.4 [Database Management]: Systems--multimedia databases; H.3.1 [Information Storage and Retrieval]: Content Analysis and Indexing--indexing methods; H.3.3 [Infomation Storage and Retrieval]: Information Search and Retrieval--search process General Terms: Algorithms, Design, Experimentation, Performance Additional Key Words and Phrases: Distance metrics, user-defined queries

Packet dropping statistics is studied for three data-link retransmission schemes, where packets are dropped at the transmitter due to: 1) buffer overflow; 2) too many transmission attempts; and 3) excessive delay. An analytical framework for the computation of the complete statistics of the dropping process and of the delay is presented and some numerical results are discussed. In particular, the dropping properties of the three different schemes are compared. The channel model considered takes into account correlated errors as occur in the wireless environment. Index Terms--Automatic retransmission request (ARQ) protocols, bursty channel, Markov errors, packet-dropping models, queueing systems, wireless packet communications.