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At least 811 records · Page 45Linked to original sources
PubMed2006

Comparison of medication adherence and associated health care costs after introduction of pioglitazone treatment in African Americans versus all other races in patients with type 2 diabetes mellitus: a retrospective data analysis.

OBJECTIVE: The aim of this study was to compare treatment adherence and health care costs in African Americans versus all other races (All Others) in patients with type 2 diabetes mellitus starting treatment with pioglitazone. METHODS: In this retrospective cohort study, the North Carolina Medicaid database was used (query dates: July 1, 2000, to June 30, 2003). Using at least 1 code from the International Classification of Diseases, Ninth Revision, Clinical Modification for type 2 diabetes (250.xx) and 1 National Drug Code for antidiabetic medication, we identified a cohort of male and female patients aged > or =18 years with type 2 diabetes who maintained continuous Medicaid eligibility for the entire 36-month follow-up period. Race was categorized as African American and All Others (white, Asian, Native American, Pacific Islander, other) based on self-reported data collected at the time of Medicaid enrollment. Medication adherence was expressed as medication possession ratio (calculated as the number of days of antidiabetic prescription supply dispensed [eg, a 30-day supply] divided by the number of days between the first and last dispensation). Reimbursements made by Medicaid were used to calculate diabetes-related and total health care costs, which included medical and dental care, including costs for regular checkups, office visits, home health care, inpatient and outpatient care, long-term care facility care, and prescription drugs. To compare the differences in medication adherence and annual total and diabetes-related health care costs between African Americans and All Others, multivariate regression analysis was performed using only data from the year after (year 2) the year in which pioglitazone treatment was started (year 1). RESULTS: Among the 1073 patients treated with pioglitazone (26.1% men; mean [SD] age, 49.5 [10.6] years; 50.2% African American; mean [SD] total health care costs in year 1, US $7906 [$12,256]; year 2, $9546 [$14,861]), African Americans had significantly higher adherence (62%) to pioglitazone treatment compared with All Others (57%) (P < 0.05) on unadjusted analysis. However, no significant differences in rates of adherence to the medication were found between African Americans and All Others on multivariate regression analysis. African American race was not found to be an independent predictor of increased or decreased annual total health care costs in this population. Significant reductions in total health care costs (2% for every 10% increase in adherence; P < 0.001) and diabetes-related costs (4% for every 10% increase in adherence; P < 0.01) with increased adherence were found. CONCLUSIONS: On multivariate analysis, this study found no significant differences in treatment adherence between African Americans versus all other races in this population of diabetic patients enrolled in a Medicaid program (query dates: July 1, 2000, to June 30, 2003). A higher adherence rate was associated with significantly lower diabetes-related and total health care costs in this population.

Adult↗
PubMedDate not supplied

Data analysis needs for health sector reform.

This paper addresses the role of information in health policy reform. It recognizes that reform can be based on data, but that there are other influences on health policy. The steps involved in making policy, including problem identification, comparison of solutions, policy adoption, implementation, and amendment, all require information. When information is unavailable for any of these steps, the policy process sometimes proceeds without it. The policy makers must make difficult choices regarding the potential benefit of comprehensive information to the policy outcome versus the potential drawbacks, in terms of time and cost, of seeking the missing information. Different areas where data are needed within health policy are enumerated, as are sources of health policy data, and examples of strategies are given. Finally, three case studies are presented, highlighting the use of information in policy making. The National Epidemiology Board in Thailand commissioned studies by experts on relevant policy topics. It had a substantial impact on changing policies in the areas of AIDS control, iodine deficiency, essential drugs and vaccination. The attempt at decentralizing health administration to the province level in Papua New Guinea is the second example presented. At the time of the evaluation, this effort had not yet attained its objectives of improving the health of the people, nor had it reduced costs or lessened inequity among regions. If this reform had been tested in a pilot project, its problems may have been discovered at an earlier stage of implementation when they would have been easier to correct. The final case concerns the UNICEF child survival interventions during the 1980s. These interventions were chosen based on cost-effectiveness analysis and were successfully implemented. The use of cost-effectiveness analysis in prioritizing interventions is one example of the way in which information can improve policy and health outcomes.

Data Collection↗
PubMed1999

Different sequence patterns in signal peptides from mycoplasmas, other gram-positive bacteria, and Escherichia coli: a multivariate data analysis.

Signal peptides are essential N-terminal extensions in export proteins, and have a positively charged N-terminus, a hydrophobic central core, and a C-terminal cleavage region. They interact in a consecutive manner with different accessory proteins during the secretion process. Potential patterns or periodicity in the amino acid (aa) sequence were searched, using multivariate techniques, for a large number of signal peptides from mollicutes (mycoplasmas), other Gram-positive bacteria, and Escherichia coli. Mollicutes signal peptides were significantly different from the E. coli and Gram-positive ones by their N-terminal charge, peptide length, and especially, unique periodicities of side chain hydrophobicity and volumes. Their lipoprotein signal peptides were longer than for any other bacteria. Significant differences were also recorded between the other bacterial peptide groups. Specific aa patterns were more related within the signal peptides from several groups of secreted bacillus enzymes, than for all signal peptides from one bacillus species. In E. coli, signal peptides from proteins routed for the various destinations revealed significant and compartment-specific sequence patterns not evident by other methods. This was substantiated from a large number of signal peptide secretion mutants for the E. coli periplasmic space. It is proposed that the differences in aa patterns and side-chain properties are related to the secondary structure sidedness and topology of the signal peptides, and important for specific interactions during the secretion process.

Amino Acid Sequence↗
PubMed1991

Detection of two-component mixtures of lognormal distributions in grouped, doubly truncated data: analysis of red blood cell volume distributions.

We have examined the statistical requirements for the detection of mixtures of two lognormal distributions in doubly truncated data when the sample size is large. The expectation-maximization algorithm was used for parameter estimation. A bootstrap approach was used to test for a mixture of distributions using the likelihood ratio statistic. Analysis of computer simulated mixtures showed that as the ratio of the difference between the means to the minimum standard deviation increases, the power for detection also increases and the accuracy of parameter estimates improves. These procedures were used to examine the distribution of red blood cell volume in blood samples. Each distribution was doubly truncated to eliminate artifactual frequency counts and tested for best fit to a single lognormal distribution or a mixture of two lognormal distributions. A single population was found in samples obtained from 60 healthy individuals. Two subpopulations of cells were detected in 25 of 27 mixtures of blood prepared in vitro. Analyses of mixtures of blood from 40 patients treated for iron-deficiency anemia showed that subpopulations could be detected in all by 6 weeks after onset of treatment. To determine if two-component mixtures could be detected, distributions were examined from untransfused patients with refractory anemia. In two patients with inherited sideroblastic anemia a mixture of microcytic and normocytic cells was found, while in the third patient a single population of microcytic cells was identified. In two family members previously identified as carriers of inherited sideroblastic anemia, mixtures of microcytic and normocytic subpopulations were found. Twenty-five patients with acquired myelodysplastic anemia were examined. A good fit to a mixture of subpopulations containing abnormal microcytic or macrocytic cells was found in two. We have demonstrated that with large sample sizes, mixtures of distributions can be detected even when distributions appear to be unimodal. These statistical techniques provide a means to characterize and quantify alterations in erythrocyte subpopulations in anemia but could also be applied to any set of grouped, doubly truncated data to test for the presence of a mixture of two lognormal distributions.

Adolescent↗
PubMed2001

A Modified General Regression Neural Network (MGRNN) with new, efficient training algorithms as a robust 'black box'-tool for data analysis.

A Modified General Regression Neural Network (MGRNN) is presented as an easy-to-use 'black box'-tool to feed in available data and obtain a reasonable regression surface. The MGRNN is based on the General Regression Neural Network by D. Specht [Specht, D. (1991). A General Regression Neural Network. IEEE Transactions on Neural Networks, 2(6), 568-576], therefore, the network's architecture and weights are determined. The kernel width of each training sample is trained by two supervised training algorithms. These fast and reliable algorithms require four user-definable parameters, but are robust against changes of the parameters. Its generalization ability was tested with different benchmarks: intertwined spirals, Mackey-Glass time series and PROBEN1. The MGRNN provides two additional features: (1) it is trainable with arbitrary data as long as a suitable metric exists. Particularly, it is unnecessary to force the data structure to vectors of equal length; (2) it is able to compute the gradient of the regression surface as long as the gradient of the metric is definable and defined. The MGRNN solves common practical problems of common feed-forward networks.

Algorithms↗
PubMed2000

[Data analysis of 492 times centrifuge examination].

Objective. To sum up the experiences and to find the regularity of centrifuge examinations. Method. The data of nine years of centrifuge examination (from 1988 to 1996) of pilots who suffered from black out or LOC frequently were analyzed. Result. There were totally 492 times centrifuge examinations. First centrifuge examination included 229 pilots, 49 qualified, 180 unqualified. Second centrifuge examination included 263 pilots, 50 qualified, 213 unqualified. The pilots were all male. The average age of first centrifuge examination was 29.27 +/- 4.87 years. Average flying time was 1015.24 +/- 131.89 h. 68.7% of their plane was JJ-6 or above. Conclusion. Most pilots undergoing centrifuge examination these nine years were 26-35 year old, and had flown for 601-1200 h. The planes they flew are mostly high-performance fighter aircraft. Close attention must be paid to pilots under similar condition by the flight surgeon. It is recommended that the special equipment of G-tolerance training should be added to the fighter aircraft units.

Acceleration↗
PubMed1984

[How consistent are personal data? Analysis of statements on the planning status of pregnancies].

The consistency of responses on the planning status of births is analyzed using data from a longitudinal fertility survey being carried out by the Demographic Institute of the Austrian Academy of Sciences. Interviews were conducted in 1978 and 1981 with a sample of two marriage cohorts; in both sets of interviews a question was asked concerning the reaction to a pregnancy at the time the woman heard about it. "After linking the data for the pregnancies leading to first or second births, a consistency index suggested by Ryder and Westoff...was applied which distinguishes between random and nonrandom consistency. For the first births a proportion of 54.4% identical answers yields a consistency index of 38.0...; for second births a proportion of 53.7% identical answers results in [a] consistency index of 30.1...." Differential consistency is also analyzed according to selected socioeconomic and demographic variables as well as a variable measuring the correspondence of husband's and wife's desired family sizes in the opinion of the husband. (summary in ENG)

Attitude↗
PubMed1986

[Correlation between quantitative indicators of the bioelectrical activity of the heart atria and central hemodynamics in patients with ischemic heart disease based on correlation analysis data].

Atrial bioelectrical activity (according to large-scale ECG findings) and central hemodynamics were studied in 43 coronary patients. A correlation analysis showed an increased correlation between the studied values in patients with diffuse and postinfarctional cardiosclerosis and those in healthy subjects. The authors stressed the most significant large-scale ECG values. A conclusion was made of the appropriateness of a study of atrial bioelectrical activity by the method of large-scale electrocardiography and hemodynamics for diagnostics in coronary patients with the initial stage of cardiac insufficiency.

Adult↗
PubMed2002

Corticosteroids improve short-term survival in patients with severe alcoholic hepatitis (AH): individual data analysis of the last three randomized placebo controlled double blind trials of corticosteroids in severe AH.

BACKGROUND/AIMS: Controversy surrounding the efficacy of corticosteroids in severe alcoholic hepatitis (AH) persists. THE AIMS OF OUR STUDY WERE: (a) to analyze individual data of patients with severe AH discriminant function (DF)> or =32 from the last three randomized controlled trials; and (b) to identify the independent prognostic factors associated with short-term survival. METHODS: Individual data were collected from the three principal investigators. Survival analysis was performed at 28 days using the Kaplan-Meier method and log-rank test. The independent prognostic values were assessed by the proportional hazards regression model. RESULTS: About 102 placebo and 113 corticosteroid patients with DF > or =32 were analyzed. At 28 days, corticosteroid patients had significantly higher survival: 84.6+/-3.4% vs. 65.1+/-4.8%, P=0.001. In univariate analysis, corticosteroid treatment, age, DF, albumin, creatinine and encephalopathy were prognostic factors. In multivariate analysis, age (P=0.0001), serum creatinine (P<0.002) and corticosteroid treatment (P=0.002) were independent prognostic variables. A more dramatic decrease of median serum bilirubin values (micromol/l) was observed at 7 and 14 days in corticosteroid patients (P<0.05) : -76.5 vs. -35 and -105 vs. -45. CONCLUSIONS: Corticosteroids improved short-term survival of patients with severe AH. Age and serum creatinine are independent prognostic factors. Corticosteroids are recommended for patients with severe AH.

Adrenal Cortex Hormones↗
PubMed2006

Retinal vein occlusion and vascular mortality: pooled data analysis of 2 population-based cohorts.

PURPOSE: To assess the association of retinal vein occlusion (RVO) with cardiovascular and cerebrovascular mortality. DESIGN: Pooled data from 2 population-based cohort studies. PARTICIPANTS: At baseline, the Beaver Dam Eye Study (BDES) examined 4926 persons aged 43 to 86 years (from 1988-1990) and the Blue Mountains Eye Study (BMES) examined 3654 persons aged 49 to 97 years (from 1992 to 1994). METHODS: Retinal vein occlusion was assessed from retinal photographs. Vascular deaths were determined using either death certificates (BDES) or the Australian National Death Index (BMES). Cox regression analysis was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). MAIN OUTCOME MEASURE: Vascular (cardiovascular and cerebrovascular) mortality was determined. RESULTS: Of 8384 baseline participants, 96 (1.14%) had RVO at baseline (BDES, n = 38; BMES, n = 58). Over 12 years, 1312 (15.7%) died of cardiovascular-related conditions and 341 (4.1%) died of cerebrovascular-related conditions. Age-standardized vascular mortality rates were 26.0% and 5.3%, respectively, in persons with RVO and 17.1% and 4.5%, respectively, in those without RVO. After adjusting for age, gender, body mass index, hypertension, diabetes, smoking, glaucoma, and study site, RVO was not associated with cardiovascular-related mortality (HR, 1.2; 95% CI, 0.8-1.8) or cerebrovascular-related mortality (HR, 0.9; 95% CI, 0.4-2.1) among participants of all ages. However, in persons aged less than 70 years, baseline RVO was associated with higher cardiovascular mortality (combined BDES and BMES: HR, 2.5; 95% CI, 1.2-5.2; BDES: HR, 2.5; 95% CI, 0.9-6.9; BMES: HR, 2.1; 95% CI, 0.7-6.8). CONCLUSIONS: Retinal vein occlusion in persons aged 43 to 69 years may signal a doubling of the risk of cardiovascular mortality.

Adult↗
PubMed2005

Data management and preliminary data analysis in the pilot phase of the HUPO Plasma Proteome Project.

The pilot phase of the HUPO Plasma Proteome Project (PPP) is an international collaboration to catalog the protein composition of human blood plasma and serum by analyzing standardized aliquots of reference serum and plasma specimens using a variety of experimental techniques. Data management for this project included collection, integration, analysis, and dissemination of findings from participating organizations world-wide. Accomplishing this task required a communication and coordination infrastructure specific enough to support meaningful integration of results from all participants, but flexible enough to react to changing requirements and new insights gained during the course of the project and to allow participants with varying informatics capabilities to contribute. Challenges included integrating heterogeneous data, reducing redundant information to minimal identification sets, and data annotation. Our data integration workflow assembles a minimal and representative set of protein identifications, which account for the contributed data. It accommodates incomplete concordance of results from different laboratories, ambiguity and redundancy in contributed identifications, and redundancy in the protein sequence databases. Recommendations of the PPP for future large-scale proteomics endeavors are described.

Algorithms↗
PubMedDate not supplied

Genomic data analysis using DNA structure: an analysis of conserved nongenic sequences and ultraconserved elements.

Recent comparative studies of the human and mouse genomes have revealed sets of conserved nongenic sequences (CNGs) and sets of ultraconserved elements (UCEs). Both sets of sequences, which exhibit extremely high levels of conservation, extend over hundreds of bases and have no known function. Since there is no detectable sequence homology between paralogous CNGs or UCEs in either of the species, an alignment-free technique is needed for their analysis. We have previously compiled a database of the structural properties of all 32,896 unique DNA octamers, including information on stability, the minimum energy conformation, and flexibility. We have used Fourier techniques to analyze the UCEs and CNGs in terms of their octamer structural properties, to reveal structural correlations which may indicate possible functions for some of these sequences.

Animals↗
PubMedDate not supplied

Reducing the numbers of the uninsured: policy implications from state-level data analysis.

The objective of the study described in this article was to identify a model that best predicts state uninsurance rates and quantifies the contribution of socio-economic factors to enable targeted state programs to reduce uninsurance. Linear regression analysis was carried out using state uninsurance rate as the dependent variable and state-level data on demographic, employment, income, and health care environment data (independent variables). For 2000 data, the model R is 0.77, indicating that 77% of the variation in uninsurance rates is explained by the percentage of immigrant population, the workforce in very small businesses, the Black population, the state's median income, and the Medicare-aged population (model R = 0.77 for 1999 and 0.68 for 1998 data). A 1% increase in immigrant population is associated with 0.18% increase in uninsurance rate. A 1% increase in workforce employed in very small businesses associates with 0.79% increase in uninsurance. The findings indicate substantial potential for reducing uninsurance through targeted state policies. Policy recommendations are made to alleviate the insurance hurdles faced by immigrant and small business employee populations.

Emigration and Immigration↗
PubMed2006

Retinal arteriolar emboli and long-term mortality: pooled data analysis from two older populations.

BACKGROUND AND PURPOSE: To assess the relationship between retinal arteriolar emboli and mortality in older people. METHODS: Pooled data from 2 population-based cohort studies. At baseline, the Beaver Dam Eye Study (BDES) examined 4926 persons 43 to 86 years of age (1988 to 1990), and the Blue Mountains Eye Study (BMES) examined 3654 persons 49 to 97 years of age (1992 to 1994). Retinal arteriolar emboli were assessed by grading retinal photographs using standardized methods. Deaths and causes of death were determined from death certificates or Australian National Death Index. Cox regression models were used to estimate mortality hazard ratios (HRs) associated with emboli, adjusting for age, gender, body mass index, hypertension, diabetes, smoking, serum total cholesterol, high-density lipoprotein cholesterol, study site, and past histories of stroke, angina, and acute myocardial infarct. RESULTS: Of 8580 baseline participants, 8384 (98%) had retinal photographs available, and 111 showed retinal arteriolar emboli (BDES n=61; BMES n=50). Over 10 to 12 years, 2506 participants (30%) died, including 344 (4%) from stroke-related and 1315 (16%) from cardiovascular causes. The cumulative mortality rates were higher in participants with than without emboli (all-cause 56% versus 30%; stroke-related 12% versus 4.0%; cardiovascular 30% versus 16%). The increased mortality risk associated with emboli was independent of age, gender, other vascular risk factors, and past histories of stroke or heart disease for all-cause (multivariate-adjusted HR, 1.3; CI, 1.0 to 1.8) and stroke-related mortality (HR, 2.0; CI, 1.1 to 3.8) but not for cardiovascular mortality (HR, 1.2; CI, 0.8 to 1.7). CONCLUSIONS: Our pooled data from 2 older populations suggest that retinal emboli predict a modest increase in all-cause and stroke-related mortality independent of cardiovascular risk factors.

Adult↗
PubMed2004

Cost of stress urinary incontinence: a claims data analysis.

OBJECTIVES: The primary objectives of this research were to: (i) identify and present methodologies for estimating three types of 'cost-of-illness' measures using healthcare and disability claims data -- specifically 'cost of treatment', 'incremental cost of patient', and 'incremental cost of illness'; and (ii) perform a case-study analysis of these cost measures for women treated for stress urinary incontinence (SUI). STUDY DESIGN AND METHODS: In this paper, we discuss aspects of cost-of-illness methodologies in the context of SUI. We first distinguish between 'cost of treatment' (i.e. the costs of treating a specific condition), 'incremental cost of patient' (i.e. the additional costs associated with patients with a particular condition, irrespective of any comorbid conditions they may also have), and 'incremental cost of illness' (i.e. the additional costs resulting from a particular illness, as distinct from the costs of other conditions that the patient might have, including conditions which might have caused the illness in question). The latter case is in many ways the most complex to model, requiring controls for related causal conditions. We then applied these three methodologies by analysing the costs associated with SUI. Using data from a large employer claims database (n > 100 000), we estimated a series of regression models that reflected cost of treatment, incremental cost of patient, and incremental cost of illness for SUI. RESULTS: The three approaches yielded substantially different results. For many purposes the incremental cost-of-illness model provides the most appropriate results, as it controls for comorbid conditions, as well as patient demographics. On a per capita basis using the incremental cost-of-illness model, patients with SUI had direct costs that were 134% more than those for their controls and indirect costs that were 163% more than those for controls. Estimating costs for the average (i.e. mean) person results in dollar-termed estimates of the costs of SUI. In particular, we found that in 1998, the average direct medical cost of SUI was $US5642 and the indirect workplace cost of SUI was $US4208. CONCLUSIONS: Since the various methods yield substantially different results, it is important that the end user of cost-of-illness analyses of claims data have a clear purpose in mind when reporting the cost of the condition of concern. The incremental cost-of-illness measure for claims data has substantial advantages in terms of enhancing our understanding of the specific cost impact of SUI.

Databases, Factual↗