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PubMed1993

Quality improvement through data analysis. Concepts and applications.

Nurse executives play a key role in quality management and need a working knowledge of which data collection and improvement tools to use. This knowledge insures effective analysis and decision making necessary to drive department and organizational transformation through quality improvement programs. The author presents the most frequently used tools for quality improvement, with a focus on applications in practice.

Appointments and Schedules↗

PubMed2000

Multistart algorithms for MEG empirical data analysis reliably characterize locations and time courses of multiple sources.

We applied our newly developed Multistart algorithm (M. Huang et al., 1998, Electroencephalogr. Clin. Neurophysiol. 108, 32-44) to high signal-to-noise ratio (SNR) somatosensory responses and low SNR visual data to demonstrate the reliability of this analysis tool for determining source locations and time courses of empirical multisource neuromagnetic data. This algorithm performs a downhill simplex search hundreds to thousands of times with multiple, randomly selected initial starting parameters from within the head volume, in order to avoid problems of local minima. Two subjects participated in two studies: (1) somatosensory (left and right median nerves were stimulated using a square wave pulse of 0.2 ms duration) and (2) visual (small black and white bull's-eye patterns were presented to central and peripheral locations in four quadrants of the visual field). One subject participated in both of the studies mentioned above and in a third study (i.e., simultaneous somatosensory/visual stimulation). The best-fitting solutions were tightly clustered in high SNR somatosensory data and all dominant regions of activity could be identified in some instances by using a single model order (e.g., six dipoles) applied to a single interval of time (e.g., 15-250 ms) that captured the entire somatosensory response. In low SNR visual data, solutions were obtained from several different model orders and time intervals in order to capture the dominant activity across the entire visual response (e.g. , 60-300 ms). Our results demonstrate that Multistart MEG analysis procedures can localize multiple regions of activity and characterize their time courses in a reliable fashion. Sources for visual data were determined by comparing results across several different models, each of which was based on hundreds to thousands of different fits to the data.

Algorithms↗

PubMed2004

A general framework for development and data analysis of competitive high-throughput screens for small-molecule inhibitors of protein-protein interactions by fluorescence polarization.

Equilibrium binding experiments are widely used for the accurate characterization of binding and competitive binding behavior in biological systems. Modern high-throughput discovery efforts in chemical biology rely heavily upon this principle. Here, we derive exact analytical expressions for general competitive binding models which can also explain a commonly encountered phenomenon in these types of experiments, anticooperative incomplete displacement. We explore the effects of nonspecific binding behavior and parameter misestimation. All expressions are derived in terms of total concentrations determined a priori. We discuss a general framework for high-throughput screening assays based on fluorescence polarization and strategies for assay development, sensitivity regimes, data quality control, analysis, and ranking. Theoretical findings are visualized by simulations using realistic parameter sets. Our results are the basis for the discovery of small-molecule inhibitors of the protein-protein interaction between human calcineurin and NFAT transcription factors, as discussed in the subsequent paper (31).

Computer Simulation↗

PubMed1999

[Value of vaccination data analysis at the district level].

This study aimed to demonstrate the importance of analysing local immunization data to improve performance of national prevention programmes. From the immunization registers kept in basic health centres, we identified 1271 children receiving their first vaccine at 3 months. Examination of the age at the subsequent vaccinations and time intervals between vaccinations showed that 81.9% had received all the vaccines required by the Ministry of Health but only 48.5% had received immunization meeting the requirements for age and time interval. The analysis also helped identify health centres with best performance (fewer children lost to follow-up and better implementation of immunization schedule) and those vaccinations needing the greatest attention from health professionals.

Age Factors↗

PubMed2006

Health care utilization among Medicare-Medicaid dual eligibles: a count data analysis.

BACKGROUND: Medicare-Medicaid dual eligibles are the beneficiaries of both Medicare and Medicaid. Dual eligibles satisfy the eligibility conditions for Medicare benefit. Dual eligibles also qualify for Medicaid because they are aged, blind, or disabled and meet the income and asset requirements for receiving Supplement Security Income (SSI) assistance. The objective of this study is to explore the relationship between dual eligibility and health care utilization among Medicare beneficiaries. METHODS: The household component of the nationally representative Medical Expenditure Panel Survey (MEPS) 1996-2000 is used for the analysis. Total 8,262 Medicare beneficiaries are selected from the MEPS data. The Medicare beneficiary sample includes individuals who are covered by Medicare and do not have private health insurance during a given year. Zero-inflated negative binomial (ZINB) regression model is used to analyse the count data regarding health care utilization: office-based physician visits, hospital inpatient nights, agency-sponsored home health provider days, and total dental visits. RESULTS: Dual eligibility is positively correlated with the likelihood of using hospital inpatient care and agency-sponsored home health services and the frequency of agency-sponsored home health days. Frequency of dental visits is inversely associated with dual eligibility. With respect to racial differences, dually eligible Afro-Americans use more office-based physician and dental services than white duals. Asian duals use more home health services than white duals at the 5% statistical significance level. The dual eligibility programs seem particularly beneficial to Afro-American duals. CONCLUSION: Dual eligibility has varied impact on health care utilization across service types. More utilization of home healthcare among dual eligibles appears to be the result of delayed realization of their unmet healthcare needs under the traditional Medicare-only program rather than the result of overutilization in response to the expanded benefits of the dual eligibility program. The dual eligibility program is particularly beneficial to Asian and Afro-American duals in association with the provision of home healthcare and dental benefits.

Aged↗

PubMed1990

Empirical considerations in orthopaedic research design and data analysis. Part III: Multivariable analysis.

To make a contribution to a base of knowledge, research design must be sound and the data must be analyzed by the most efficient, powerful method available. In conducting orthopaedic research as well as when interpreting the orthopaedic literature, knowledge of multivariable analysis is essential in evaluating the effects of variables that may confound or influence the relationship of interest. An understanding of the basic tenets, underlying assumptions, and purposes of frequently used types of multivariable analysis is necessary for an accurate, critical evaluation of a study's results.

Humans↗

PubMed1993

Quantitative evaluation of drug-induced erythema by using a tristimulus colour analyzer: experimental design and data analysis.

Pulsed-light reflectance using the Minolta Chroma Meter CR-200 was evaluated as a quantitative method for the noninvasive assessment of drug-induced erythema on the flexor surface of the forearm. Nicotinate esters were used as model vasodilators. Several parameters derived from the data were analysed using analysis of variance (ANOVA) and Tukey's multiple range tests appropriate for the study designs used. The effects of varying concentrations of methylnicotinate and of different nicotinate esters were found to be statistically significant. This non-invasive technique was found to be particularly useful in ranking the cutaneous responses elicited by the topical application of increasing concentrations of methylnicotinate in a single subject, as well as in a group of 6 volunteers.

Adult↗

PubMed2005

Optimizing data analysis tools to support healthcare workers in Peru.

Large healthcare projects in developing countries need to track data for clinical care, patient outcomes, medication supplies, and research. These heterogeneous information needs are compounded by the wide range of skills and experience of staff. We describe analysis tools designed to bridge these requirements in a tuberculosis (TB) treatment project in Peru.

Decision Support Systems, Clinical↗

PubMed2004

Metabolic discrimination of Catharanthus roseus leaves infected by phytoplasma using 1H-NMR spectroscopy and multivariate data analysis.

A comprehensive metabolomic profiling of Catharanthus roseus L. G. Don infected by 10 types of phytoplasmas was carried out using one-dimensional and two-dimensional NMR spectroscopy followed by principal component analysis (PCA), an unsupervised clustering method requiring no knowledge of the data set and used to reduce the dimensionality of multivariate data while preserving most of the variance within it. With a combination of these techniques, we were able to identify those metabolites that were present in different levels in phytoplasma-infected C. roseus leaves than in healthy ones. The infection by phytoplasma in C. roseus leaves causes an increase of metabolites related to the biosynthetic pathways of phenylpropanoids or terpenoid indole alkaloids: chlorogenic acid, loganic acid, secologanin, and vindoline. Furthermore, higher abundance of Glc, Glu, polyphenols, succinic acid, and Suc were detected in the phytoplasma-infected leaves. The PCA of the (1)H-NMR signals of healthy and phytoplasma-infected C. roseus leaves shows that these metabolites are major discriminating factors to characterize the phytoplasma-infected C. roseus leaves from healthy ones. Based on the NMR and PCA analysis, it might be suggested that the biosynthetic pathway of terpenoid indole alkaloids, together with that of phenylpropanoids, is stimulated by the infection of phytoplasma.

Catharanthus↗

PubMed1996