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PubMedDate not supplied

Creating a pediatric digital library for pediatric health care providers and families: using literature and data to define common pediatric problems.

The goal of this study was to complete a literature-based needs assessment with regard to common pediatric problems encountered by pediatric health care providers (PHCPs) and families, and to develop a problem-based pediatric digital library to meet those needs. The needs assessment yielded 65 information sources. Common problems were identified and categorized, and the Internet was manually searched for authoritative Web sites. The created pediatric digital library (www.generalpediatrics.com) used a problem-based interface and was deployed in November 1999. From November 1999 to November 2000, the number of hyperlinks and authoritative Web sites increased 51.1 and 32.2 percent, respectively. Over the same time, visitors increased by 57.3 percent and overall usage increased by 255 percent. A pediatric digital library has been created that begins to bring order to general pediatric resources on the Internet. This pediatric digital library provides current, authoritative, easily accessed pediatric information whenever and wherever the PHCPs and families want assistance.

Computer Systems↗
PubMed1984

Retention data for antibiotics commonly used for bovine infections.

This study was designed to observe the maximum time that various antibiotics used in different ways as treatment of bovine infections persisted in milk after final treatment. Both Delvotest-P and Bacillus stearothermophilus (Difco) disc assay procedures were utilized for detection of antibiotic preparations used for treatment of mastitis. None persisted in milk longer than specified on their respective labels. Because antibiotic residues were detected in milk consequent to treatment for intrauterine infections, guidelines for withholding times following intrauterine treatment should be established.

Animals↗
PubMed1999

Application of the missing-indicator method in matched case-control studies with incomplete data.

A common practice in matched case-control studies with incomplete data is to perform two analyses in parallel: a matched analysis of the complete pairs and an unmatched analysis of all subjects carried out after breaking the matching in the complete pairs. The missing-indicator method, which has the advantage of making use of the data in the incomplete pairs while still preserving the matching in the complete pairs, is recommended as an alternative method of analysis. It is shown here that its estimate of the odds ratio is a compromise between the odds ratios estimated by a matched analysis of the complete pairs and an unmatched analysis of the incomplete pairs. The method is illustrated using data from a matched case-control study of the risk of childhood leukemia from exposure to residential electric and magnetic fields.

Biometry↗
PubMed2002

Assessment of forearm volumetric bone mineral density from standard areal densitometry data.

The common bone density measurement procedures produce areal bone mineral density data (BMD) alone. Volumetric bone density is thought to offer a different diagnostic perspective and is usually measured by peripheral quantitative computed tomography. We developed a calculation procedure for radial and ulnar volumetric densities based on single X-ray absorptiometry. The study consisted of 418 healthy Bulgarian females (ages 20 83 yr). Forearm bone density was measured on a DTX-100 densitometer at the 8-mm distal site, and the total volumetric bone densities of radius and ulna were calculated. The accuracy error determined on cadaveric bones was 10 14%. The in vivo precision error was 1.0 1.1%. Age-matched reference curves for volumetric BMD (vBMD) were built. Peak values were registered in the age 30 34 group: 0.403 (radius) and 0.469 g/cm(3) (ulna). Ulnar volumetric density exceeded the radial one, representing an interesting finding to be further investigated. For the age 70 74 group, vBMD was reduced by approx 30% compared with the age 30 34 group. Our data confirmed the fact that volumetric density was much less affected by age and menopause. Correlations between forearm vBMD and axial BMD were moderate. The proposed calculation procedure could become an extra option in forearm bone densitometry to be applied in pediatric populations or adults of extremely large or small body size.

Absorptiometry, Photon↗
PubMed1993

Don't bleach chaotic data.

A common first step in time series signal analysis involves digitally filtering the data to remove linear correlations. The residual data is spectrally white (it is "bleached"), but in principle retains the nonlinear structure of the original time series. It is well known that simple linear autocorrelation can give rise to spurious results in algorithms for estimating nonlinear invariants, such as fractal dimension and Lyapunov exponents. In theory, bleached data avoids these pitfalls. But in practice, bleaching obscures the underlying deterministic structure of a low-dimensional chaotic process. This appears to be a property of the chaos itself, since nonchaotic data are not similarly affected. The adverse effects of bleaching are demonstrated in a series of numerical experiments on known chaotic data. Some theoretical aspects are also discussed.

Journal Article↗
PubMed2005

Common strategies in clinical data collection displayed by experienced clinician-teachers in internal medicine.

The role model displayed by clinician-teachers influences learning experiences but learners may face various reasoning styles. Our goal was to describe common strategies in clinical data collection displayed by experienced clinician-teachers in internal medicine. We studied six internists heavily involved in teaching while they were working up the same seven cases portrayed by a standardized patient. Each encounter was audio-recorded and replayed to allow the subjects commenting on the purpose and diagnostic hypotheses considered for each piece of information collected. Information and hypotheses elicited by all physicians were considered key items. Although the subjects reached the same final diagnoses, they differed on several characteristics of their data collection process. They also displayed common behaviours, such as: early acquisition of key data (half of them acquired within the first 19 questions asked) through clarification of the patients' complaints and focused data collection; early generation of the final diagnosis (within the first 10 questions asked) and use of diagnostic hypotheses to frame data collection; and summarization of the information at hand during the encounter (at least twice). Whether making teachers explicitly conscious about their own reasoning processes may help them better model and explain their diagnostic approach to specific cases should be assessed in follow-up studies.

Adolescent↗
PubMed1997

A generalized estimating equation approach for modeling random length binary vector data.

A common measure in clinical trials and epidemiologic studies is the number of events such as seizures, hospitalizations, or bouts of disease. Frequently, a binary measure of severity for each event is available but is not incorporated in the analysis. This paper proposes methodology for jointly modeling the number of events and the vector of correlated binary severity measures. Our formulation exploits the notion that a given covariate may affect both outcomes in a similar way. We functionally link the regression parameters for the counts and binary means and discuss a generalized estimating equation (GEE) approach for parameter estimation. We discuss conditions under which the proposed joint modeling approach provides marked gains in efficiency relative to the common procedure of simply modeling the counts, and we illustrate the methodology with epilepsy clinical trial data.

Anticonvulsants↗
PubMed1993

A statistical test of compatibility of data sets to a common dose-response model.

Quantitative estimates of cancer risk generally involve low-dose extrapolation based on an exponential dose-response model for dichotomous response data. Frequently more than one data set is available. If a careful analysis of the biological issues indicates that more than one of the available data sets could be used in the quantitative estimate of cancer risk, it is reasonable to think of combining the data. Before combining data, however, it would be prudent to test whether the data sets are compatible with a common dose-response model. If they are not, it could be concluded that an underlying biological factor is responsible. If they are statistically compatible, the decision to combine data sets based on biological issues would be reinforced. A statistical test based on the generalized likelihood ratio method is proposed for evaluating the compatibility of different data sets with a common dose-response model. This method of constructing a statistical test and the associated asymptotic theory is consistent with the approach used by GLOBAL86 (R. B. Howe, K. S. Crump, and C. Van Landingham, GLOBAL86: A Computer Program to Extrapolate Quantal Animal Toxicity Data to Low Doses, K. S. Crump & Co., Ruston, LA, 1986) for estimating the confidence limits that are used as a basis for quantitative estimates.

Animals↗
PubMed2003

Methodological issues in the use of published cartoons as data.

When common understanding of a phenomenon is under investigation, mass media representation in general, and cartoon images in particular, are a useful source of data. Sample selection, data collection, and the analysis of constructed images differ from other kinds of data. Cartoonists may intend to stimulate multiple interpretations among readers. Uncovering these interpretations is essential to understanding public discourse of the phenomenon of interest. Semantic validation is used to assess the degree to which the meanings of text relative to their context are accurately represented. Analysis of the image and text of cartoons has the potential to yield important understanding of public discourse surrounding issues of the public's health and well-being.

Cartoons as Topic↗
PubMed2007

Proteomic data exchange and storage: the need for common standards and public repositories.

The ever increasing volumes of proteomic data now being produced by laboratories across the world have resulted in major issues in data storage and accessibility. The further demands of multilaboratory initiatives has highlighted issues when collaborators cannot import data generated within the same project but generated by different hardware types and processed by laboratory-specific work flows and analyses packages. There is an increasing need for common data standards that will allow the interchange of data between different instrumentation, search engines, and between laboratory databases. This could then lead to the establishment of data repositories from where benchmark datasets could be accessed and reanalyzed. The Human Proteome Organization is currently supporting efforts to establish such standards. The work of the Proteomics Standards Initiative has lead to the development of the mzData XML interchange standard and is now broadening its scope to produce a spectral analysis output format, mzIdent. Accompanying controlled vocabularies allow the accurate, while systematic, representation of metadata throughout both schema.

Benchmarking↗
PubMed2004

Significance analysis of ROC indices for comparing diagnostic markers: applications to gene microarray data.

A common objective in microarray experiments is to select genes that are differentially expressed between two classes (two treatment groups). Selection of differentially expressed genes involves two steps. The first step is to calculate a discriminatory score that will rank the genes in order of evidence of differential expressions. The second step is to determine a cutoff for the ranked scores. Summary indices of the receiver operating characteristic (ROC) curve provide relative measures for a ranking of differential expressions. This article proposes using the hypothesis-testing approach to compute the raw p-values and/or adjusted p-values for three ROC discrimination measures. A cutoff p-value can be determined from the (ranked) p-values or the adjusted p-values to select differentially expressed genes. To quantify the degree of confidence in the selected top-ranked genes, the conditional false discovery rate (FDR) over the selected gene set and the "Type I" (false positive) error probability for each selected gene are estimated. The proposed approach is applied to a public colon tumor data set for illustration. The selected gene sets from three ROC summary indices and the commonly used two-sample t-statistic are applied to the sample classification to evaluate the predictability of the four discrimination measures.

Algorithms↗
PubMedDate not supplied

[Common stressor proteins in bacteria].

Research data on common stressor proteins of bacteria obtained during recent 10 years are updated and analyzed. Bacteria of one and the same species were shown to give similar response to the action of different stressors; the main stressor proteins of different bacteria appeared to be homologous; bacteria have cross protection from different stressors. In addition, some common stressor proteins of bacteria were found to be homologous with human antigens that is of great importance for immunobiotechnology.

Bacteria↗
PubMed1999

Postweaning performance of calves from Angus, Brahman, and reciprocal-cross cows grazing endophyte-infected tall fescue or common bermudagrass.

Data from 403 Polled Hereford-sired calves from Angus, Brahman, and reciprocal-cross cows were used to evaluate the effects of preweaning forage environment on postweaning performance. Calves were spring-born in 1991 to 1994 and managed on either endophyte-infected tall fescue (E+) or common bermudagrass (BG) during the preweaning phase. After weaning, calves were shipped to the Grazinglands Research Laboratory, El Reno, OK and stratified to one of two winter stocker treatments by breed and preweaning forage; stocker treatments were winter wheat pasture (WW) or native range plus supplemental CP (NR). Each stocker treatment was terminated in March, calves grazed cool-season grasses, and calves were then moved to a feedlot phase in June. In the feedlot phase, calves were fed to approximately 10 mm fat over the 12th rib and averaged approximately 115 d on feed. When finished, calves were weighed and shipped to Amarillo, TX for slaughter. Averaged over calf breed group, calves from E+ gained faster during the stocker phase (P<.10), had lighter starting and finished weights on feed (P< .01), lighter carcass weights (P<.01), and smaller longissimus muscle areas (P<.05) than calves from BG. Calves from E+ were similar to calves from BG in feedlot ADG, percentage kidney, heart, and pelvic fat, fat thickness over 12th rib, yield grade, marbling score, and dressing percentage. Maternal heterosis was larger in calves from E+ for starting weight on feed (P<.01), finished weight (P<.10), and carcass weight (P<.16). These data suggest that few carryover effects from tall fescue preweaning environments exist, other than lighter, but acceptable, weights through slaughter. These data further suggest that the tolerance to E+ in calves from reciprocal-cross cows, expressed in weaning weights, moderated postweaning weight differences between E+ and BG compared to similar comparisons in calves from purebred cows.

Animal Feed↗