bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamic Assessment of Health Outcomes: Time to Let the CAT Out of the Bag?
Authors: Cook Karon F. , O'Malley Kimberly J. , Roddey Toni S. 
Published: September 2005

Background.The use of item response theory (IRT) to measure self‐reported outcomes has burgeoned in recent years. Perhaps the most important application of IRT is computer‐adaptive testing (CAT), a measurement approach in which the selection of items is tailored for each respondent.Objective.To provide an introduction to the use of CAT in the measurement of health outcomes, describe several IRT models that can be used as the basis of CAT, and discuss practical issues associated with the use of adaptive scaling in research settings.Principal Points.The development of a CAT requires several steps that are not required in the development of a traditional measure including identification of “starting” and “stopping” rules. CAT's most attractive advantage is its efficiency. Greater measurement precision can be achieved with fewer items. Disadvantages of CAT include the high cost and level of technical expertise required to develop a CAT.Conclusions.Researchers, clinicians, and patients benefit from the availability of psychometrically rigorous measures that are not burdensome. CAT outcome measures hold substantial promise in this regard, but their development is not without challenges.
Proxies and Other External Raters: Methodological Considerations
Authors: Lynn Snow A. , Cook Karon F. , Lin Pay‐Shin , Morgan Robert O. , Magaziner Jay 
Published: September 2005

Objective. The purpose of this paper is to introduce researchers to the measurement and subsequent analysis considerations involved when using externally rated data. We will define and describe two categories of externally rated data, recommend methodological approaches for analyzing and interpreting data in these two categories, and explore factors affecting agreement between self‐rated and externally rated reports. We conclude with a discussion of needs for future research.Data Sources/Study Setting. Data sources for this paper are previous published studies and reviews comparing self‐rated with externally rated data.Study Design/Data Collection/Extraction Methods. This is a psychometric conceptual paper.Principal Findings. We define two types of externally rated data: proxy data and other‐rated data. Proxy data refer to those collected from someone who speaks for a patient who cannot, will not, or is unavailable to speak for him or herself, whereas we use the term other‐rater data to refer to situations in which the researcher collects ratings from a person other than the patient to gain multiple perspectives on the assessed construct. These two types of data differ in the way the measurement model is defined, the definition of the gold standard against which the measurements are validated, the analysis strategies appropriately used, and how the analyses are interpreted. There are many factors affecting the discrepancies between self‐ and external ratings, including characteristics of the patient, the proxy, and of the rated construct. Several psychological theories can be helpful in predicting such discrepancies.Conclusions. Externally rated data have an important place in health services research, but use of such data requires careful consideration of the nature of the data and how it will be analyzed and interpreted.
Measurement Issues in Health Disparities Research
Authors: Ramírez Mildred , Ford Marvella E. , Stewart Anita L. , A. Teresi Jeanne 
Published: September 2005

Background.Racial and ethnic disparities in health and health care have been documented; the elimination of such disparities is currently part of a national agenda. In order to meet this national objective, it is necessary that measures identify accurately the true prevalence of the construct of interest across diverse groups. Measurement error might lead to biased results, e.g., estimates of prevalence, magnitude of risks, and differences in mean scores. Addressing measurement issues in the assessment of health status may contribute to a better understanding of health issues in cross‐cultural research.Objective.To provide a brief overview of issues regarding measurement in diverse populations.Findings.Approaches used to assess the magnitude and nature of bias in measures when applied to diverse groups include qualitative analyses, classic psychometric studies, as well as more modern psychometric methods. These approaches should be applied sequentially, and/or iteratively during the development of measures.Conclusions.Investigators performing comparative studies face the challenge of addressing measurement equivalence, crucial for obtaining accurate results in cross‐cultural comparisons.
Impact of Institutional Review Board Practice Variation on Observational Health Services Research
Authors: Green Lee A. , Lowery Julie C. , Kowalski Christine P. , Wyszewianski Leon 
Published: September 2005

Objective. To describe, qualitatively and quantitatively, the impact of a review by multiple institutional review boards (IRBs) on the conduct of a multisite observational health services research study.Data Source and Setting. Primary data collection during 2002, 2003, and 2004 at 43 United States Department of Veterans Affairs (VA) primary care clinics.Design: Explanatory sequential mixed methods design incorporating qualitative and quantitative elements in sequence.Data Collection and Abstraction Methods: Field notes and documents collected by research staff during a multisite observational health services research study were used in thematic analysis. Themes were quantified descriptively and merged with timeline data.Principal Findings: Approximately 4,680 hours of staff time over a 19‐month period were devoted solely to the IRB process. Four categories of phenomena impacting research were observed:(1) Recruitment, retention, and communication issues with local site principal investigators (PIs). Local PIs had no real role but were required by IRBs. Twenty‐one percent of sites experienced turnover in local PIs, and local PI issues added significant delay to most sites.(2) Wide variation in standards applied to review and approval of IRB applications. The study was designed to be qualified under U.S. government regulations for expedited review. One site exempted it from review (although it did not qualify for exemption), 10 granted expedited review, 31 required full review, and one rejected it as being too risky to be permitted. Twenty‐three required inapplicable sections in the consent form and five required HIPAA (Health Insurance Portability and Accountability Act of 1996) consent from physicians although no health information was asked of them. Twelve sites requested, and two insisted upon, provisions that directly increased the risk to participants.(3) Multiple returns for revision of IRB applications, consent documents, and ancillary forms. Seventy‐six percent of sites required at least one resubmission, and 15 percent of sites required three or more (up to six) resubmissions. Only 12 percent of sites required any procedural or substantive revision; most resubmissions were editorial changes to the wording of the consent document.(4) Process failures (long turnaround times, lost paperwork, difficulty in obtaining necessary forms, unavailability of key personnel at IRBs). The process required from 52 to 798 (median 286) days to obtain approval at each site.Conclusions. Several features of the IRB system as currently configured impose costly burdens of administrative activity and delay on observational health services research studies, and paradoxically decrease protection of human subjects. Central review with local opt‐out, cooperative review, or a system of peer review could reduce costs and improve protection of human subjects.
The Effects of Child‐Only Insurance Coverage and Family Coverage on Health Care Access and Use: Recent Findings among Low‐Income Children in California
Authors: Guendelman Sylvia , Wier Megan , Angulo Veronica , Oman Doug 
Published: September 2005

Objective. To compare the extent with which child‐only and family coverage (child and parent insured) ensure health care access and use for low income children in California and discuss the policy implications of extending the State Children's Health Insurance Program (California's Healthy Families) to uninsured parents of child enrollees.Data Sources/Setting. We used secondary data from the 2001 California Health Interview Survey (CHIS), a representative telephone survey.Study Design. We conducted a cross‐sectional study of 5,521 public health insurance–eligible children and adolescents and their parents to examine the effects of insurance (family coverage, child‐only coverage, and no coverage) on measures of health care access and utilization including emergency room visits and hospitalizations.Data Collection. We linked the CHIS adult, child, and adolescent datasets, including the adolescent insurance supplement.Findings. Among the sampled children, 13 percent were uninsured as were 22 percent of their parents. Children without insurance coverage were more likely than children with child‐only coverage to lack a usual source of care and to have decreased use of health care. Children with child‐only coverage fared worse than those with family coverage on almost every access indicator, but service utilization was comparable.Conclusions. While extending public benefits to parents of children eligible for Healthy Families may not improve child health care utilization beyond the gains that would be obtained by exclusively insuring the children, family coverage would likely improve access to a regular source of care and private sector providers, and reduce perceived discrimination and breaks in coverage. These advantages should be considered by states that are weighing the benefits of expanding health insurance to parents.
Psychometric Properties of the Dutch Version of the Hospital‐Level Consumer Assessment of Health Plans Survey®Instrument
Authors: Arah Onyebuchi A. , Ten Asbroek A. H. A. , Delnoij Diana M. J. , De Koning Johan S. , Stam Piet J. A. , Poll Aldien H. , Vriens Barbara , Schmidt Paul F. , Klazinga Niek S. 
Published: September 2005

Objectives.To assess the reliability and validity of a translated version of the American Hospital‐level Consumer Assessment of Health Plans Survey® (H‐CAHPS) instrument for use in Dutch health care.Data Sources/Study Setting.Primary survey data from adults aged 18 years or more who were recently discharged from two multispecialty city hospitals in the Netherlands.Study Design.We used forward and backward translation procedures and a panel of experts to adapt the 66‐item pilot H‐CAHPS into a 70‐item Dutch instrument. Descriptive statistics and standard psychometric methods were then used to test the reliability and validity of the new instrument.Data Collection.From late November 2003 to early January 2004, the survey was administered by mail to 1,996 patients discharged within the previous 2 months.Principal Findings.Analyses supported the reliability and validity of the following 7‐factor H‐CAHPS structure for use in Dutch hospitals: on doctor's communication, nurses' communication, discharge information, communication about medication, pain control, physical environment of hospital, and nursing services. The internal consistency reliability of the scales ranged from 0.60 to 0.88. Items related to “family receiving help when on visit,”“hospital staff introducing self,” and “admission delays” did not improve the psychometric properties of the new instrument.Conclusions.These findings suggest that the H‐CAHPS instrument is reliable and valid for use in the Dutch context. However, more research will be needed to support its equivalence to the United States version, and its use for between‐hospital comparisons.
Seroprevalence and Risk Factors for Helicobacter pylori Infection in Greenlanders
Authors: Koch Anders , Krause Tyra Grove , Krogfelt Karen , Olsen Ove Rosing , Fischer Thea Kølsen , Melbye Mads 
Published: September 2005

ABSTRACTBackground.  In contrast to most populations worldwide, the incidence of gastric cancer increases among Inuit in Greenland. Contributing factors to this increase are unknown, but Helicobacter pylori may be involved. However, little is known regarding the epidemiology of H. pylori in Arctic communities. With the aim of determining age‐specific prevalence, risk factors, and association with clinical conditions of H. pylori infection, we carried out a population‐based study of H. pylori in Sisimiut, the second biggest town of Greenland.Materials and Methods.  A population‐based sample of 685 persons had serum drawn that was analyzed for H. pylori IgG antibodies using enzyme‐linked immunosorbent assay (ELISA). Risk factors analyses were carried out using multivariate logistic regression models.Results.  The seroprevalence was lowest among children aged 0–4 years (6%), but increased rapidly thereafter. In persons aged 15–87 years the seroprevalence had stabilized around 58%. Total number of children in household, number of older, but not younger, siblings and narrow age gap to closest older sibling were associated with H. pylori seropositivity. In contrast, number of adults in household and socioeconomic status did not influence serostatus.Conclusions.  The age‐specific prevalence pattern in Greenland is intermediate between that of developing and developed countries. The risk factor pattern indicates crowding and older siblings in particular to be key elements in risk of infection.
Corporate Yield Spreads: Default Risk or Liquidity? New Evidence from the Credit Default Swap Market
Authors: LONGSTAFF FRANCIS A. , MITHAL SANJAY , NEIS ERIC 
Published: September 2005

ABSTRACTWe use the information in credit default swaps to obtain direct measures of the size of the default and nondefault components in corporate spreads. We find that the majority of the corporate spread is due to default risk. This result holds for all rating categories and is robust to the definition of the riskless curve. We also find that the nondefault component is time varying and strongly related to measures of bond‐specific illiquidity as well as to macroeconomic measures of bond market liquidity.
Wanna Dance? How Firms and Underwriters Choose Each Other
Authors: FERNANDO CHITRU S. , GATCHEV VLADIMIR A. , SPINDT PAUL A. 
Published: September 2005

ABSTRACTWe develop and test a theory explaining the equilibrium matching of issuers and underwriters. We assume that issuers and underwriters associate by mutual choice, and that underwriter ability and issuer quality are complementary. Our model implies that matching is positive assortative, and that matches are based on firms' and underwriters' relative characteristics at the time of issuance. The model predicts that the market share of top underwriters and their average issue quality varies inversely with issuance volume. Various cross‐sectional patterns in underwriting spreads are consistent with equilibrium matching. We find strong empirical confirmation of our theory.
The Market Impact of Trends and Sequences in Performance: New Evidence
Authors: DURHAM GREGORY R. , HERTZEL MICHAEL G. , MARTIN J. SPENCER 
Published: September 2005

ABSTRACTBloomfield and Hales (2002) find strong evidence that experimental market subjects are influenced by trends and patterns in a manner supportive of the shifting regimes model of Barberis, Shleifer, and Vishny (1998). We subject the model to further empirical scrutiny using the football wagering market as our price laboratory. Sports betting markets have several advantages over traditional capital markets as an empirical setting, and commonalities with traditional markets allow for useful insights. We find scant evidence that investors behave in accordance with the model.
The management of dry skin with topical emollients – recent perspectives
Authors: Proksch Ehrhardt , Lachapelle Jean‐Marie 
Published: September 2005

SummaryDry skin (xerosis) is a common symptom of a number of chronic skin diseases, such as atopic dermatitis, but can also be caused by environmental factors, such as cold weather and frequent showering. The condition can cause unsightliness of the skin, discomfort, itching, and can have a negative impact on patients' quality of life. This article will cover recent developments in the understanding of xerosis and its management with emollients. The stratum corneum consists of corneocytes and lipid‐enriched intercellular bilayers. These are both produced from keratinocytes in a process called epidermal differentiation. Disturbed epidermal differentiation, resulting in the impairment of stratum corneum intercellular lipid bilayers and natural moisturizing factor, is the root cause of xerosis. The constituent ingredients of emollients should, therefore, address the different factors that contribute to dry skin and, most importantly, attempt to restore epidermal differentiation. The use of lipids, physiological lipids, humectants and antipruritics will help to restore the lipid lamellae, improve skin hydration, skin elasticity and prevent itching. The ideal emollient will include these ingredients plus an agent to support epidermal differentiation. Selecting the correct emollient product and using it regularly are vital factors in the management of xerosis.
„Lues maligna” bei insulinpflichtigem Diabetes mellitus
Authors: Hofmann Uta B. , Hund Martina , Bröcker Eva‐Bettina , Hamm Henning 
Published: September 2005

ZusammenfassungBei einer 40‐jährige Patientin mit insulinpflichtigem Diabetes mellitus traten innerhalb weniger Wochen vor allem am Stamm multiple bis 2,5 cm große, lividrote Knoten und Plaques auf, die rasch ulzerierten. Einige Monate zuvor habe beim Partner ein kleines Ulkus am Penis bestanden. Die HIV‐negative Patientin hatte eine hochtitrig positive Syphilisserologie (TPPA‐Titer > 1 : 20.480, VDRL‐Titer 1 : 128). Die nüchtern Blutglukosewerte lagen über 275 mg/dl. Nach Ausschluss einer Neurolues stellten wir die Diagnose einer „Lues maligna” bei schlecht eingestelltem Diabetes mellitus. Unter einer Therapie mit 3 Injektionen Benzylpenicillin‐Benzathin (2,4 Mio. IE) i. m. in wöchentlichen Abständen und Einstellung des Diabetes heilten die Hautveränderungen komplett ab. Im Verlauf war der VDRL‐Titer negativ.Die „Lues maligna” tritt seit einigen Jahren wieder gehäuft auf und wird vor allem bei HIV‐positiven Männern beobachtet. Das Auftreten dieser Erkrankung bei durch Diabetes mellitus bedingter Immunsuppression ist ausgesprochen selten.
Molecular characterization and expression of caprine (Capra hircus) interleukin‐18 cDNA
Authors: Hosamani M. , Mondal B. , Muneta Y. , Rasool T. J. 
Published: September 2005

SummaryInterleukin 18 (IL‐18) has been identified as a potent upstream cytokine required for upregulation of IFN‐γ secretion that plays a crucial role in polarization of Th1 type of immune response. Considering the potential applications of the cytokine in immunomodulation, it has been characterized in many livestock species including cattle, equines, canines, felines and porcines. In this paper we report the isolation, cloning sequencing and expression of caprine precursor IL‐18. Full‐length caprine IL‐18 cDNA was isolated from mitogen‐stimulated adherent peripheral blood mononuclear cells using reverse transcription polymerase chain reaction (RT‐PCR). The cDNA contained an open reading frame of 579 bp encoding a putative polypeptide of 192 amino acids. Deduced amino acid sequence of caprine IL‐18 showed varying amino acid identity with the published sequences of other domestic ruminant species ranging from 94.3% to 96.9%, while it shared over 78% aa identity with other domestic animals. Pairwise multiple aligned sequences showed a deletion of Glu31in caprine IL‐18 unlike in other species. Recombinant caprine IL‐18 was produced in Escherichia coli, which cross‐reacted with two antiporcine IL‐18 monoclonal antibodies.
Short term effects of particulate matter on cause specific mortality: effects of lags and modification by city characteristics
Authors: Zeka A , Zanobetti A , Schwartz J 
Published: September 2005

Background:Consistent evidence has shown increased all-cause mortality, and mortality from broad categories of causes associated with airborne particles. Less is known about associations with specific causes of death, and modifiers of those associations.Aims:To examine these questions in 20 US cities, between 1989 and 2000.Methods:Mortality files were obtained from the National Center for Health Statistics. Air pollution data were obtained from the Environmental Protection Agency website. The associations between daily concentrations of particulate matter of aero-diameter ⩽10 μm (PM10) and daily mortality from all-cause and selected causes of death, were examined using a case-crossover design. Temporal effects of PM10were examined using lag models, in first stage regressions. City specific modifiers of these associations were examined in second stage regressions.Results:All-cause mortality increased with PM10exposures occurring both one and two days prior the event. Deaths from heart disease were primarily associated with PM10on the two days before, while respiratory deaths were associated with PM10exposure on all three days. Analyses using only one lag underestimated the effects for all-cause, heart, and respiratory deaths. Several city characteristics modified the effects of PM10on daily mortality. Important findings were seen for population density, percentage of primary PM10from traffic, variance of summer temperature, and mean of winter temperature.Conclusions:There was overall evidence of increased daily mortality from increased concentrations of PM10that persisted across several days, and matching for temperature did not affect these associations. Heterogeneity in the city specific PM10effects could be explained by differences in certain city characteristics.
Integrin αVβ3as a Target for Blocking HIV-1 Tat-Induced Endothelial Cell Activation In Vitro and Angiogenesis In Vivo
Authors: Urbinati Chiara , Mitola Stefania , Tanghetti Elena , Kumar Chandra , Waltenberger Johannes , Ribatti Domenico , Presta Marco , Rusnati Marco 
Published: September 2005

Objective—The transactivating factor (Tat) of HIV-1 binds to αvβ3integrin present on endothelial cells contributing to neovascularization. Here, we investigated the biological consequences of Tat/αvβ3interaction and the antagonist effect of an Arg-Gly-Asp (RGD)-based peptidomimetic.Methods and Results—Binding of Tat to endothelial αvβ3triggers focal adhesion kinase and nuclear factor-κB activation, leading to endothelial cell proliferation, membrane ruffling, and motility in vitro and neovascularization in vivo. The RGD-peptidomimetic SCH221153 inhibits Tat/αvβ3interaction in a solid phase binding assay and endothelial cell adhesion to immobilized Tat with a potency higher than that of RGD-containing peptides. Accordingly, SCH221153 inhibits Tat/αvβ3-dependent focal adhesion kinase and nuclear factor-κB activation, proliferation, membrane ruffling, and motility in endothelial cells. Finally, SCH221153 inhibits the angiogenic response triggered by Tat in the chick-embryo chorioallantoic membrane without affecting physiological vascularization. SCH221153 exerts these inhibitory effects without affecting the interaction of Tat with endothelial heparan sulfate proteoglycans or with the vascular endothelial growth factor receptor-2/kinase domain–containing receptor. In all the assays the negative control SCH216687 was ineffective.Conclusion—These data provide new insights on the mechanism of endothelial cell activation by Tat and point to RGD peptidomimetics as prototypes for the development of novel Tat antagonists.