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Aggregate Data (aggregate + data)
Selected AbstractsTHE USE OF AGGREGATE DATA TO ESTIMATE GOMPERTZ-TYPE OLD-AGE MORTALITY IN HETEROGENEOUS POPULATIONSAUSTRALIAN & NEW ZEALAND JOURNAL OF STATISTICS, Issue 4 2009Christopher R. Heathcote Summary We consider two related aspects of the study of old-age mortality. One is the estimation of a parameterized hazard function from grouped data, and the other is its possible deceleration at extreme old age owing to heterogeneity described by a mixture of distinct sub-populations. The first is treated by half of a logistic transform, which is known to be free of discretization bias at older ages, and also preserves the increasing slope of the log hazard in the Gompertz case. It is assumed that data are available in the form published by official statistical agencies, that is, as aggregated frequencies in discrete time. Local polynomial modelling and weighted least squares are applied to cause-of-death mortality counts. The second, related, problem is to discover what conditions are necessary for population mortality to exhibit deceleration for a mixture of Gompertz sub-populations. The general problem remains open but, in the case of three groups, we demonstrate that heterogeneity may be such that it is possible for a population to show decelerating mortality and then return to a Gompertz-like increase at a later age. This implies that there are situations, depending on the extent of heterogeneity, in which there is at least one age interval in which the hazard function decreases before increasing again. [source] An empirical analysis of US and Japanese health insurance using age,period,cohort decompositionHEALTH ECONOMICS, Issue 5 2007Kosei Fukuda Abstract Aggregate data on household health insurance expenditure in the US and Japan that are classified by period and age are decomposed into age, period, and cohort effects by using the Bayesian cohort models. These models are developed to overcome the identification problem involved in cohort analysis. Despite the differences between the health insurance systems of the two countries, three interesting empirical findings are obtained. First, in both the countries, the age effects are the most influential, and the cohort effects have negligible influence. The latter provides a striking policy implication since the generational imbalance in social security expenditures is widely recognized in developed countries. Second, in both the countries, the period effects show a roughly upward trend. Finally, the age effects exhibit a roughly upward movement for all age groups in the US; however, in Japan, these effects show a downward movement for the 55,59 age group due to the changes in the health insurance system on retirement. Copyright © 2006 John Wiley & Sons, Ltd. [source] Mapping Internationalization: Domestic and Regional ImpactsINTERNATIONAL STUDIES QUARTERLY, Issue 4 2001Etel Solingen This article introduces a conceptual design for mapping the domestic impact of internationalization. It proposes that internationalization leads to a trimodal domestic coalitional profile and advances a set of expectations about the regional effects of each profile. Aggregate data from ninety-eight coalitions in nineteen states over five regions suggests that between 1948 and 1993 the three coalitional types differed in their international behavior. Internationalizing coalitions deepened trade openness, expanded exports, attracted foreign investments, restrained military-industrial complexes, initiated fewer international crises, eschewed weapons of mass destruction, deferred to international economic and security regimes, and strove for regional cooperative orders that reinforced those objectives. Backlash coalitions restricted or reduced trade openness and reliance on exports, curbed foreign investment, built expansive military complexes, developed weapons of mass destruction, challenged international regimes, exacerbated civic-nationalist, religious, or ethnic differentiation within their region, and were prone to initiate international crises. Hybrids straddled the grand strategies of their purer types, intermittently striving for economic openness, contracting the military complex, initiating international crises, and cooperating regionally and internationally, but neither forcefully nor coherently. These findings have significant implications for international relations theory and our incipient understanding of internationalization. Further extensions of the conceptual framework can help capture international effects that are yet to be fully integrated into the study of the domestic politics of coalition formation. [source] Child-free and unmarried: Changes in the life planning of young east German womenJOURNAL OF MARRIAGE AND FAMILY, Issue 5 2004Marina A. Adler Using evidence from demographic and survey data, this research examines how one decade of postsocialism has changed the life planning of young East German women. Aggregate data reflect marriage and fertility postponement and increased nonmarital birth rates and cohabitation. The analysis shows East German women's "stubbornness" (Dölling, 2003) in adhering to life perspectives in line with the German Democratic Republic (GDR) standard biography (high nonmarital childbearing, high work orientation, rejection of the homemaker status, desire to combine work and family). The most important findings are that (a) motherhood is postponed to increase child-free time, (b) cohabitation is increasingly becoming an alternative to marriage, (c) marriage (but not partnership) is increasingly optional for childbearing, and (d) employment is prioritized over family formation. [source] Antibiotic use in five children's hospitals during 2002,2006: the impact of antibiotic guidelines issued by the Chinese Ministry of Health,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 3 2008Wenshuang Zhang Abstract Purpose To investigate the pattern of antibiotic use in five Chinese children's hospitals from 2002 to 2006. To see if the Guidelines to encourage rational use of antibiotics issued by the Ministry of Health in October 2004 have any impact on the use. Methods The Anatomical Therapeutic Chemical Classification/Defined Daily Doses (ATC/DDD) methodology was used. Aggregate data on antibiotic use (ATC code-J01) were expressed in numbers of DDD/100 bed-days for inpatients. Results Total 56 different substances of systemic antibiotics were used. The overall consumption of antibiotic drugs was 68.2, 58.4, 65.8, 65.6 and 49.9 DDD/100 bed-days for the years 2002,2006, respectively. The top antibiotics used were third-generation cephalosporins. There was considerable variation in both type and amount of antibiotics used in the five hospitals. In 2002, some hospitals had twice the antibiotic use compared to others. While the overall antibiotic use in 2005 was largely unchanged compared with previous years, by 2006 antibiotic use had decreased by 22.6% and the variation in use between hospitals was also reduced. Conclusions The ATC/DDD methodology proved useful for studying overall antibiotic usage in children's hospitals. The decline in antibiotic usage found in 2006 (and the reduced variation between hospitals) may be attributed to the impact of the Ministry of Health guidelines which took some time to be promulgated to individual staff members. Further research will focus on compliance of antibiotic use in these five hospitals with particular guideline recommendations for specific clinical problems such as bacterial resistance and surgical antibiotic prophylaxis. Copyright © 2007 John Wiley & Sons, Ltd. [source] A COHORT ANALYSIS OF US AGE,EARNINGS PROFILESBULLETIN OF ECONOMIC RESEARCH, Issue 2 2008Kosei Fukuda J31; C51 ABSTRACT Aggregate data on US earnings, classified by period and by age, are decomposed into age, period and cohort effects, using the Bayesian cohort models, which were developed to overcome the identification problem in cohort analysis. The main findings, obtained by comparing college and high school graduates, are threefold. First, the age effects show a downward trend for the age group of 45,49 onwards for high school graduates but do not show any such trend for college graduates. Second, the period effects show a downward trend for high school graduates but reveal no such trend for college graduates. Third, the cohort effects are negligible for both college and high school graduates. [source] Effect of redundancy on the mean time to failure of wireless sensor networksCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 8 2007Anh Phan Speer Abstract In data-driven wireless sensor networks (WSNs), the system must perform data sensing and retrieval and possibly aggregate data as a response at runtime. As a WSN is often deployed unattended in areas where replacements of failed sensors are difficult, energy conservation is of primary concern. While the use of redundancy is desirable in terms of satisfying user queries to cope with sensor and transmission faults, it may adversely shorten the lifetime of the WSN, as more sensor nodes will have to be used to answer queries, causing the energy of the system to drain quickly. In this paper, we analyze the effect of redundancy on the mean time to failure (MTTF) of a WSN in terms of the number of queries the system is able to answer correctly before it fails due to either sensor/transmission faults or energy depletion. In particular, we analyze the effect of redundancy on the MTTF of cluster-structured WSNs for energy conservations. We show that a tradeoff exists between redundancy and MTTF. Furthermore, an optimal redundancy level exists such that the MTTF of the system is maximized. Copyright © 2007 John Wiley & Sons, Ltd. [source] Aggregate time-series regression in the field of alcoholADDICTION, Issue 7 2001Jürgen Rehm Time-series regression of successive aggregate data has been used widely to explore relationships between substance use and harm, or to measure effects of policy interventions. This paper suggests minimal standards to conduct such analyses with respect to validity and reliability of underlying data, statistical techniques and requirements and interpretation of results. [source] Alcohol and mortality: methodological and analytical issues in aggregate analysesADDICTION, Issue 1s1 2001Thor Norström This supplement includes a collection of papers that aim at estimating the relationship between per capita alcohol consumption and various forms of mortality, including mortality from liver cirrhosis, accidents, suicide, homicide, ischaemic heart disease, and total mortality. The papers apply a uniform methodological protocol, and they are all based on time series data covering the post-war period in the present EU countries and Norway. In this paper we discuss various methodological and analytical issues that are common to these papers. We argue that analysis of time series data is the most feasible approach for assessing the aggregate health consequences of changes in population drinking. We further discuss how aggregate data may also be useful for judging the plausibility of individual-level relationships, particularly those prone to be confounded by selection effects. The aggregation of linear and curvilinear risk curves is treated as well as various methods for dealing with the time-lag problem. With regard to estimation techniques we find country specific analyses preferable to pooled cross-sectional/time series models since the latter incorporate the dubious element of geographical co-variation, and conceal potentially interesting variations in alcohol effects. The approach taken in the papers at hand is instead to pool the country specific results into three groups of countries that represent different drinking cultures; traditional wine countries of southern Europe, beer countries of central Europe and the British Isles and spirits countries of northern Europe. The findings of the papers reinforce the central tenet of the public health perspective that overall consumption is an important determinant of alcohol-related harm rates. However, there is a variation across country groups in alcohol effects, particularly those on violent deaths, that indicates the potential importance of drinking patterns. There is no support for the notion that increases in per capita consumption have any cardioprotective effects at the population level. [source] Healthcare in a land called PeoplePower: nothing about me without meHEALTH EXPECTATIONS, Issue 3 2001Tom Delbanco MD In a 5-day retreat at a Salzburg Seminar attended by 64 individuals from 29 countries, teams of health professionals, patient advocates, artists, reporters and social scientists adopted the guiding principle of ,nothing about me without me' and created the country of PeoplePower. Designed to shift health care from ,biomedicine' to ,infomedicine', patients and health workers throughout PeoplePower join in informed, shared decision-making and governance. Drawing, where possible, on computer-based guidance and communication technologies, patients and clinicians contribute actively to the patient record, transcripts of clinical encounters are shared, and patient education occurs primarily in the home, school and community-based organizations. Patients and clinicians jointly develop individual ,quality contracts', serving as building blocks for quality measurement and improvement systems that aggregate data, while reflecting unique attributes of individual patients and clinicians. Patients donate process and outcome data to national data banks that fuel epidemiological research and evidence-based improvement systems. In PeoplePower hospitals, constant patient and employee feedback informs quality improvement work teams of patients and health professionals. Volunteers work actively in all units, patient rooms are information centres that transform their shape and decor as needs and individual preferences dictate, and arts and humanities programmes nourish the spirit. In the community, from the earliest school days the citizenry works with health professionals to adopt responsible health behaviours. Communities join in selecting and educating health professionals and barter systems improve access to care. Finally, lay individuals partner with professionals on all local, regional and national governmental and private health agencies. [source] Information technology innovation diffusion: an information requirements paradigmINFORMATION SYSTEMS JOURNAL, Issue 3 2008Nigel Melville Abstract., Information technology (IT) innovation research examines the organizational and technological factors that determine IT adoption and diffusion, including firm size and scope, technological competency and expected benefits. We extend the literature by focusing on information requirements as a driver of IT innovation adoption and diffusion. Our framework of IT innovation diffusion incorporates three industry-level sources of information requirements: process complexity, clock speed and supply chain complexity. We apply the framework to US manufacturing industries using aggregate data of internet-based innovations and qualitative analysis of two industries: wood products and beverage manufacturing. Results show systematic patterns supporting the basic thesis of the information processing paradigm: higher IT innovation diffusion in industries with higher information processing requirements; the salience of downstream industry structure in the adoption of interorganizational systems; and the role of the location of information intensity in the supply chain in determining IT adoption and diffusion. Our study provides a new explanation for why certain industries were early and deep adopters of internet-based innovations while others were not: variation in information processing requirements. [source] Low Public Expenditures on Social Welfare: Do East Asian Countries have a Secret?INTERNATIONAL JOURNAL OF SOCIAL WELFARE, Issue 1 2000David Jacobs This paper explores the sources of low public expenditures on social welfare in Japan, Korea, Taiwan, Hong Kong and Singapore. Six factors are analysed based on aggregate data: the public/private mix of welfare programmes, the age structure, the maturity of old-age pension schemes, the population coverage of social security, the relative generosity of social security and the role of enterprises and families as alternative providers of welfare. The evidence allows putting some conventional statements about the virtues of East Asian welfare states into questions. Public expenditures on welfare are bound to rise a lot in Japan, Korea and Taiwan, while the level of protection in Hong Kong and Singapore is well below the standards of Western countries. [source] Variations in Immigrant Incorporation in the Neighborhoods of AmsterdamINTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 3 2006JOHN R. LOGAN Amsterdam's immigrants of Caribbean and southern Mediterranean origin have been characterized as modestly segregated from Dutch residents, and their residential assimilation has been expected to proceed rapidly. This article tests the hypothesis of spatial assimilation using both aggregate data on levels of segregation and individual-level analyses of the people who live in ethnic minority neighborhoods. Evidence is presented of assimilation for immigrants from the former colonies of Surinam and the Antilles, but Turks and Moroccans are shown to face stronger barriers. The former groups' higher standing favors their mobility from ethnically distinct neighborhoods. There is a generational shift for Surinamese and Antilleans, while the Turks and Moroccans born in Amsterdam are as likely as the immigrant generation to settle in ethnic minority neighborhoods. [source] Individual patient data meta-analysis of randomized anti-epileptic drug monotherapy trialsJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 2 2000Paula R. Williamson PhD Abstract Meta-analysis may be based on either aggregate data or individual patient data (IPD). Three reasons why IPD are desirable for the meta-analysis of anti-epileptic drug (AED) monotherapy trials are: (1) to undertake a more complete analysis of time-to-event outcomes; (2) to investigate the interaction between AED and type of epilepsy; and (3) to undertake re-analysis of the trial to obtain results for all relevant outcomes. We demonstrate that IPD meta-analysis is possible in AED research. Problems arose from missing data at four levels: (1) unknown trials; (2) known trials but no IPD supplied; (3) known trials but missing outcome data for some individuals within trials; and (4) known trials but missing covariate data for some individuals within trials. Empirical evidence of the reliability of meta-analyses based on aggregate rather than individual patient data is still lacking. Examples of other benefits such projects may bring include improvements to the design of a new trial in the area, in terms of the sample size considerations, the definition of outcomes and data collection. [source] DISCUSSION II ON FITTING EQUATIONS TO SENSORY DATAJOURNAL OF SENSORY STUDIES, Issue 1 2000STEVEN M. SEIFERHELD ABSTRACT In his article " On Fitting Equations to Sensory Data." Moskowitz suggests many strategies for model fitting which depart from current statistical methodology. Four areas discussed by Moskowitz are addressed here: (1) Forcing terms into a model; (2) The use of hold-out samples; (3) The use of aggregate data (averaging across people, suppressing the person-to-person variation); and (4) The use of random data as a predictor variable in a regression equation. All four of these points will be examined within this article. [source] Fiskalischer Wettbewerb und EinkommensumverteilungPERSPEKTIVEN DER WIRTSCHAFTSPOLITIK, Issue 2 2000Lars P. Feld Fiscal competition is supposed to lead to the collapse of the welfare state because, first, it will become difficult for a single jurisdiction to levy a redistribution tax upon the rich and mobile, and second, such a policy, if undertaken in one jurisdiction, will attract poor individuals from other jurisdictions and erode the internal redistribution policy. In this paper, theoretical and empirical studies concerning the impact of taxes and transfer payments on residence decisions of taxpayers are reviewed. The relationship of fiscal competition and the erosion of the welfare state is illustrated with aggregate data on income redistribution in Switzerland. [source] Meta-analysis of a binary outcome using individual participant data and aggregate dataRESEARCH SYNTHESIS METHODS, Issue 1 2010Richard D. Riley Abstract In this paper, we develop meta-analysis models that synthesize a binary outcome from health-care studies while accounting for participant-level covariates. In particular, we show how to synthesize the observed event-risk across studies while accounting for the within-study association between participant-level covariates and individual event probability. The models are adapted for situations where studies provide individual participant data (IPD), or a mixture of IPD and aggregate data. We show that the availability of IPD is crucial in at least some studies; this allows one to model potentially complex within-study associations and separate them from across-study associations, so as to account for potential ecological bias and study-level confounding. The models can produce pertinent population-level and individual-level results, such as the pooled event-risk and the covariate-specific event probability for an individual. Application is made to 14 studies of traumatic brain injury, where IPD are available for four studies and the six-month mortality risk is synthesized in relation to individual age. The results show that as individual age increases the probability of six-month mortality also increases; further, the models reveal clear evidence of ecological bias, with the mean age in each study additionally influencing an individual's mortality probability. Copyright © 2010 John Wiley & Sons, Ltd. [source] Economic transition and elections in Poland1THE ECONOMICS OF TRANSITION, Issue 1 2003John E. Jackson Abstract Poland's economic and political transition, one of the most successful, has depended very heavily on job creation in new firms to replace the jobs lost in the formerly state-owned enterprises. This paper uses survey and aggregate data from three Polish elections to suggest that these de novo firms, the individuals they employ, and the residents in the local areas where they exist become an important constituency supporting pro-reform political parties and constraining the actions of parties less sympathetic to the reforms. The creation of this political constituency helps explain how countries can successfully pursue both economic and political reforms. JEL classification: D72, P26. [source] What Ever Happened to N-of-1 Trials?THE MILBANK QUARTERLY, Issue 4 2008Insiders' Perspectives, a Look to the Future Context: When feasible, randomized, blinded single-patient (n-of-1) trials are uniquely capable of establishing the best treatment in an individual patient. Despite early enthusiasm, by the turn of the twenty-first century, few academic centers were conducting n-of-1 trials on a regular basis. Methods: The authors reviewed the literature and conducted in-depth telephone interviews with leaders in the n-of-1 trial movement. Findings: N-of-1 trials can improve care by increasing therapeutic precision. However, they have not been widely adopted, in part because physicians do not sufficiently value the reduction in uncertainty they yield weighed against the inconvenience they impose. Limited evidence suggests that patients may be receptive to n-of-1 trials once they understand the benefits. Conclusions: N-of-1 trials offer a unique opportunity to individualize clinical care and enrich clinical research. While ongoing changes in drug discovery, manufacture, and marketing may ultimately spur pharmaceutical makers and health care payers to support n-of-1 trials, at present the most promising resuscitation strategy is stripping n-of-1 trials to their essentials and marketing them directly to patients. In order to optimize statistical inference from these trials, empirical Bayes methods can be used to combine individual patient data with aggregate data from comparable patients. [source] Temporal aggregation of Markov-switching financial return modelsAPPLIED STOCHASTIC MODELS IN BUSINESS AND INDUSTRY, Issue 3 2009Wai-Sum Chan Abstract In this paper we investigate the effects of temporal aggregation of a class of Markov-switching models known as Markov-switching normal (MSN) models. The growing popularity of the MSN processes in modelling financial returns can be attributed to their inherited flexibility characteristics, allowing for heteroscedasticity, asymmetry and excess kurtosis. The distributions of the process described by the basic MSN model and the model of the corresponding temporal aggregate data are derived. They belong to a general class of mixture normal distributions. The limiting behaviour of the aggregated MSN model, as the order of aggregation tends to infinity, is studied. We provide explicit formulae for the volatility, autocovariance, skewness and kurtosis of the aggregated processes. An application of measuring solvency risk with MSN models for horizons larger than 1 year and up to 10 years from the baseline U.S. S&P 500 stock market total return time series spanning about 50 years is given. Copyright © 2008 John Wiley & Sons, Ltd. [source] Spatial Cluster Detection for Weighted Outcomes Using Cumulative Geographic ResidualsBIOMETRICS, Issue 3 2010Andrea J. Cook Summary Spatial cluster detection is an important methodology for identifying regions with excessive numbers of adverse health events without making strong model assumptions on the underlying spatial dependence structure. Previous work has focused on point or individual-level outcome data and few advances have been made when the outcome data are reported at an aggregated level, for example, at the county- or census-tract level. This article proposes a new class of spatial cluster detection methods for point or aggregate data, comprising of continuous, binary, and count data. Compared with the existing spatial cluster detection methods it has the following advantages. First, it readily incorporates region-specific weights, for example, based on a region's population or a region's outcome variance, which is the key for aggregate data. Second, the established general framework allows for area-level and individual-level covariate adjustment. A simulation study is conducted to evaluate the performance of the method. The proposed method is then applied to assess spatial clustering of high Body Mass Index in a health maintenance organization population in the Seattle, Washington, USA area. [source] Estimating Transition Probabilities from Aggregate Samples Plus Partial Transition DataBIOMETRICS, Issue 3 2000D. L. Hawkins Summary. Longitudinal studies often collect only aggregate data, which allows only inefficient transition probability estimates. Barring enormous aggregate samples, improving the efficiency of transition probability estimates seems to be impossible without additional partial-transition data. This paper discusses several sampling plans that collect data of both types, as well as a methodology that combines them into efficient estimates of transition probabilities. The method handles both fixed and time-dependent categorical covariates and requires no assumptions (e.g., time homogeneity, Markov) about the population evolution. [source] Spatial Yield Risk Across Region, Crop and Aggregation MethodCANADIAN JOURNAL OF AGRICULTURAL ECONOMICS, Issue 2-3 2005Michael Popp A researcher interested in crop yield risk analysis often has to contend with a lack of field- or farm-level data. While spatially aggregated yield data are often readily available from various agencies, aggregation distortions for farm-level analysis may exist. This paper addresses how much aggregation distortion might be expected and whether findings are robust across wheat, canola and flax grown in two central Canadian production regions, differing mainly by rainfall, frost-free growing days and soil type. Using Manitoba Crop Insurance Corporation data from 1980 to 1990, this research, regardless of crop or region analyzed, indicates that (i) spatial patterns in risk are absent; (ii) use of aggregate data overwhelmingly under-estimates field-level yield risk; and (iii) use of a relative risk measure compared to an absolute risk measure leads to slightly less aggregation distortion. Analysts interested in conducting farm-level analysis using aggregate data are offered a range of adjustment factors to adjust for potential bias. Un chercheur qui s'intéresse à l'analyse du risque du rendement des cultures doit souvent composer avec un manque de micro-données provenant de l'exploitation. Bien qu'il soit possible d'obtenir des données sur les rendements spatialement cumulées auprès de divers organismes, ces données peuvent comporter des distorsions importantes dues à l'agrégation des données de base et être trompeuses si elles sont utilisées pour effectuer des analyses à l'échelle de l'exploitation. Le présent article traite de la quantité de distorsion due à l'agrégation à laquelle on doit s'attendre et examine si les résultats obtenus pour le blé, le canola et le lin dans deux principales régions productrices canadiennes, où les précipitations, les jours de croissance sans gel et le type de sol constituent les principales différences, sont robustes ou non. À l'aide des données obtenues auprès de la Société d'assurance-récolte du Manitoba pour la période 1980,1990, la présente étude, sans égard à la culture ou à la région analysée, indique (i) que les profils régionaux en matière de risque n'existent pas; (ii) que l'utilisation de données agrégées sous-estime considérablement le risque de rendement; (iii) que l'utilisation d'une mesure du risque relatif comparativement à une mesure du risque absolu entraîne légèrement moins de distorsion d'agrégation. Afin d'ajuster les données pour minimiser un biais éventuel, nous proposons une gamme de facteurs d'ajustement aux analystes intéressés à effectuer des analyses à l'échelle des exploitations à l'aide de données agrégées. [source] Hospital and Demographic Influences on the Disposition of Transient Ischemic AttackACADEMIC EMERGENCY MEDICINE, Issue 2 2008Jeffrey H. Coben MD Abstract Objectives:, There is substantial variation in the emergency department (ED) disposition of patients with transient ischemic attack (TIA), and the factors responsible for this variation have not been determined. In this study, the authors examined the influence of clinical, sociodemographic, and hospital characteristics on ED disposition. Methods:, All ED-treated TIA cases from community hospitals in 11 states were identified from the 2002 Healthcare Cost and Utilization Project (HCUP). Using the aggregate data, descriptive analyses compared admitted and discharged cases. Pearson's chi-square test was used to determine the statistical significance of these comparisons. Based on the results of the bivariate analyses, logistic regression models of the likelihood of hospital admission were derived, using a stepwise selection process. Adjusted risk ratios and 95% confidence intervals (CI) were calculated from the logistic regression models. Results:, A total of 34,843 cases were identified in the 11 states, with 53% of cases admitted to the hospital. In logistic regression models, differences in admission status were found to be strongly associated with clinical characteristics such as age and comorbidities. After controlling for comorbidities, differences in admission status were also found to be associated to hospital type and with sociodemographic characteristics, including county of residence and insurance status. Conclusions:, While clinical factors predictably and appropriately impact the ED disposition of patients diagnosed with TIA, several nonclinical factors are also associated with differences in disposition. Additional research is needed to better understand the basis for these disparities and their potential impact on patient outcomes. [source] | ||||||||||||||||||||||