bluuebunny/crossref_metadata_2025_split huggingface dataset:
Association of socioeconomic and demographic factors with utilization of rheumatology subspecialty care in systemic lupus erythematosus
Authors: Yazdany Jinoos , Gillis Joann Zell , Trupin Laura , Katz Patricia , Panopalis Pantelis , Criswell Lindsey A. , Yelin Edward 
Published: April 2007

AbstractObjectiveTo examine the role of sociodemographic factors (age, race/ethnicity, and sex) and socioeconomic factors (income and education) in the utilization of rheumatology subspecialty care in a large cohort of subjects with systemic lupus erythematosus (SLE).MethodsData were derived from a cohort of 982 English‐speaking subjects with SLE. Between 2002 and 2004, trained survey workers administered a telephone survey to subjects eliciting information regarding demographics, SLE disease status, medications, health care utilization, health insurance, and socioeconomic status. We identified predictors of utilization of rheumatology subspecialty care, defined as at least 1 visit to a rheumatologist in the previous year. In addition, we examined factors associated with identifying any specialist as primarily responsible for SLE care.ResultsOlder age, lower income, Medicare insurance, male sex, and less severe disease were associated with lack of rheumatology care. However, race/ethnicity and educational attainment were not significantly related to seeing a rheumatologist. After multivariate adjustment, only older age, lower income, and male sex remained associated with absence of rheumatology visits. Those least likely to identify a specialist as primarily responsible for their SLE care included older subjects and those reporting lower incomes.ConclusionAlthough elderly subjects and those with lower incomes traditionally have access to health care through the Medicare and Medicaid programs, the presence of health insurance alone did not ensure equal utilization of care. This finding suggests that additional barriers to accessing rheumatology subspecialty care may exist in these patient populations.
Influence of familial factors on radiologic disease progression over two years in siblings with osteoarthritis at multiple sites: A prospective longitudinal cohort study
Authors: Botha‐Scheepers Stella A. , Watt Iain , Slagboom Eline , Meulenbelt Ingrid , Rosendaal Frits R. , Breedveld Ferdinand C. , Kloppenburg Margreet 
Published: April 2007

AbstractObjectiveThe contribution of genetics to osteoarthritis (OA) progression is not known. To gain more insight into whether familial factors play a role in disease progression of OA, we analyzed familial aggregation of radiologic OA progression in a study of sibling pairs (the Genetics, Arthrosis, and Progression [GARP] study).MethodsA total of 105 white probands and their 105 siblings with OA at multiple joint sites were included in a prospective cohort study. Radiologic progression of OA was defined as a 1‐point score increase in total scores for severity of joint space narrowing (JSN) or osteophytes on standardized radiographs of the hands, knees, and hips obtained at baseline and after 2 years. Odds ratios were calculated for siblings and probands sharing radiologic disease progression.ResultsA total of 100 probands and 93 siblings were followed for 2 years (median age 60 years, 80% women). In 92 sibling pairs both the proband and sibling had complete radiographic followup. Radiologic progression of JSN and osteophytes was present in 47% and 42% of the probands and 34% and 37% of the siblings, respectively. The odds ratios (95% confidence intervals), adjusted for age, sex, and body mass index, of a sibling having radiologic progression if the proband had progression were 3.0 (1.2–7.8) for JSN progression and 1.5 (0.6–3.6) for osteophyte progression. A dose‐response relationship was found between the amount of increase in JSN total scores among probands and the progression of JSN in siblings.ConclusionFamilial factors played a role in the radiologic progression of JSN over 2 years in patients with OA at multiple sites.
Accuracy of the diagnoses of spondylarthritides in veterans affairs medical center databases
Authors: Singh Jasvinder A. , Holmgren Aaron R. , Krug Hollis , Noorbaloochi Siamak 
Published: April 2007

AbstractObjectiveTo study the accuracy of diagnoses of spondylarthritides in computerized databases at the Minneapolis Veterans Affairs Medical Center.MethodsMedical records were available and reviewed for a random sample of 184 patients from a cohort of 737 patients seen at the rheumatology clinic between January 1, 2001 and July 31, 2002. We compared 4 database definitions with the medical record gold standard of rheumatologists' diagnosis of ankylosing spondylitis (AS), psoriatic arthritis (PsA), or reactive arthritis (ReA): presence of 1) ≥1 or 2) ≥2 International Classification of Diseases, Ninth Revision (ICD‐9) diagnostic codes for diagnoses of AS (720.0), PsA (696.0), and ReA (099.3, 711.11–711.19), and presence of 3) ≥1 or 4) ≥2 ICD‐9 codes and prescription of a disease‐modifying antirheumatic drug (DMARD). Accuracy was assessed by sensitivity, specificity, positive predictive values (PPVs) and negative predictive values (NPVs), kappa statistic, and receiver operator characteristic (ROC) curve area.ResultsOf 184 patients, 11 (6%) had AS, 17 (9%) had PsA, and 7 (4%) had ReA as per the gold standard. ICD‐9 codes for AS, PsA, and ReA were very specific (98–100%) with excellent NPV (99–100%) and PPV (83–100%), good to excellent sensitivity (57–100%), almost perfect kappa agreement (0.72–1), and high ROC curve area (0.79–1). Addition of presence of DMARD prescription to ICD‐9 codes of AS and PsA decreased sensitivity to 27–65% without improving the specificity (which was already high at 99–100%).ConclusionThe ICD‐9 codes for AS, PsA, and ReA in databases are accurate. ICD‐9 codes may be used to identify cohorts of patients with spondylarthritides.
US national prevalence and correlates of low back and neck pain among adults
Authors: Strine Tara W. , Hootman Jennifer M. 
Published: April 2007

AbstractObjectiveTo estimate the US prevalence and psychological and health behavior correlates of low back pain and/or neck pain. No current US national prevalence estimates of low back and neck pain exist and few studies have investigated the associations between low back and neck pain, psychological factors, and health behaviors in a representative sample of US community dwellers.MethodsWe analyzed data obtained from adults ages 18 years or older (n = 29,828) who participated in the 2002 National Health Interview Survey, a cross‐sectional, population‐based survey of US adults.ResultsThe 3‐month US prevalence of back and/or neck pain was 31% (low back pain: 34 million, neck pain: 9 million, both back and neck pain: 19 million). Generally, adults with low back and/or neck pain reported more comorbid conditions, exhibited more psychological distress (including serious mental illness), and engaged in more risky health behaviors than adults without either condition.ConclusionLow back and neck pain are critical public health problems. Our study supports the idea of a multidimensional approach to examining low back and neck problems and suggests the need for further research to address potentially modifiable psychological factors and health behaviors in these populations.
Validation of a short form of the Western Ontario and McMaster Universities Osteoarthritis Index function subscale in hip and knee osteoarthritis
Authors: Baron Gabriel , Tubach Florence , Ravaud Philippe , Logeart Isabelle , Dougados Maxime 
Published: April 2007

AbstractObjectiveA short version of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function scale has recently been developed to enhance the applicability of the scale in routine practice and clinical research for patients with hip and knee osteoarthritis. The goal of the present study was to validate this short form.MethodsWe conducted a prospective 4‐week cohort study of 1,036 outpatients. Performance on the WOMAC function long form (LF) and short form (SF) was compared. Agreement between responses on the 2 forms was examined according to a Bland‐Altman plot. Responsiveness to change (by standardized response mean [SRM]), reproducibility (intraclass correlation coefficient [ICC]), and internal consistency (Cronbach's alpha) were computed for both forms. Construct validity was assessed based on functional impairment as measured on a numerical rating scale.ResultsAt baseline, 24% of patients who completed the WOMAC LF had missing data for at least 1 item as compared with only 6% of patients who completed the WOMAC SF. The mean WOMAC SF score was greater than the mean WOMAC LF score (mean ± SD difference −4.3 ± 4.8 on a 0–100 scale). SRMs were 0.61 and 0.73, ICCs were 0.76 and 0.68, and Cronbach's alphas were 0.93 and 0.85 for the WOMAC LF and SF, respectively. The 2 forms had comparable correlation with functional impairment.ConclusionThe WOMAC function short form has a low rate of missing data and is a responsive, reproducible, and valid measure. The mean SF score was 4 points higher than the mean LF score.
Tolerance and effectiveness of anti–tumor necrosis factor α therapies in elderly patients with rheumatoid arthritis: A population‐based cohort study
Authors: Genevay Stéphane , Finckh Axel , Ciurea Adrian , Chamot Anne‐Marie , Kyburz Diego , Gabay Cem ,   Physicians of the Swiss Clinical Quality Management Program for Rheumatoid Arthritis
Published: April 2007

AbstractObjectiveLimited data have been published on tolerance to and efficacy of classic or biologic disease‐modifying antirheumatic drugs in elderly patients with rheumatoid arthritis (RA). The goal of the present study was to evaluate the tolerance to and effectiveness of anti–tumor necrosis factor (anti‐TNF) agents in elderly patients (≥65 years old) with RA (ERA) in comparison with younger patients (YRA).MethodsThe Swiss Clinical Quality Management program for RA is a longitudinal population‐based cohort. All patients who had received at least 1 dose of anti‐TNF agents between January 1997 and November 2005 were included and categorized according to their age. Tolerance was assessed by analyzing discontinuation rates of anti‐TNF agents. Effectiveness of these agents was assessed by analyzing RA disease activity (Disease Activity Score in 28 joints [DAS28]) and functional disability (Health Assessment Questionnaire [HAQ]) after anti‐TNF initiation.ResultsAmong 1,571 patients with RA treated with anti‐TNF agents, 344 were ≥65 years of age at treatment initiation. Drug discontinuation rates (median time 3 years) and mean change in DAS28 scores at 2 years (–0.65 versus –0.58) were identical in ERA and YRA. However, HAQ score improved significantly less in ERA (–0.02) than in YRA (–0.1) and a subsequent analysis revealed that this finding was essentially due to patients >75 years of age.ConclusionAge in itself should not interfere with the decision to treat elderly patients with RA with anti‐TNF agents. In a subset of patients ages >75 years, no functional improvement according to HAQ should be expected despite improvements in disease activity.
Comparison of energy expenditure from lifestyle physical activities between patients with rheumatoid arthritis and healthy controls
Authors: Mancuso Carol A. , Rincon Melina , Sayles Wendy , Paget Stephen A. 
Published: April 2007

AbstractObjectiveLow energy expenditure is a risk for cardiovascular morbidity. The goals of this study were to compare energy expenditure between patients with rheumatoid arthritis (RA) and healthy controls.MethodsA total of 121 RA patients and 120 healthy controls in New York City completed the Paffenbarger Physical Activity and Exercise Index at time of enrollment (1999–2000) and 1 year later to measure energy expenditure from walking, climbing stairs, and exercise/sports. Analyses were adjusted for age, sex, education, pain, social support, and depressive symptoms and were compared with recommended thresholds of energy expenditure.ResultsParticipants' mean age was 49 years, and 87% were women. Patients with RA expended fewer kilocalories per week than controls (mean ± SD 1,474 ± 1,198 versus 1,958 ± 1,940, P = 0.003), with most of this difference from less walking as opposed to high‐intensity activities. Although similar percents of RA patients and controls met national recommendations for total weekly energy expenditure (56% versus 64% for the lower [≥1,000 kilocalories per week] threshold; P = 0.14, and 41% versus 48% for the higher [≥1,400 kilocalories per week] threshold; P = 0.17), fewer RA patients met the recommendations (≥700 kilocalories per week) for walking (32% versus 48%; P = 0.01). The strongest predictor of more energy expenditure at 1 year for both groups was more energy expenditure at enrollment.ConclusionMost of the difference in energy expenditure between RA patients and healthy controls was due to less walking. Given that walking is an effective and relatively safe lifestyle activity, increasing walking should be a priority to improve cardiovascular risk in RA.
Spannbetontragwerke von Straßenbrücken – Bemessungsvergleich nach neuen Nationalen Normen und bisherigen Europäischen Normen
Authors: Roßner Wolfgang 
Published: April 2007

AbstractMit Blick auf die endgültigen Europäischen Normen (EN) werden zunächst die Nachweiskonzepte der neuen Nationalen Normen (DIN) und der Europäischen Vornormen (ENV) unter Einschluss der zusätzlichen nationalen Regelungen gegenübergestellt und die vorhandenen Abweichungen aufgezeigt. Anschließend werden die daraus resultierenden Auswirkungen in den Grenzzuständen der Tragfähigkeit und der Gebrauchstauglichkeit verglichen und anhand einer einfeldrigen Spannbetonbrücke mit Kastenquerschnitt quantifiziert.
Test Statistics for Simple MARKOV Chains. A Monte Carlo Study
Authors: Bedall Fritz K. 
Published: April 2007

AbstractThe statistical method for the analysis of frequency tables which has been published by GRIZZLE, STARMER, and KOCH (1969) is outlined for the case of linear functions of relative frequencies. Its use for the analysis of aggregate time series data under the model of simple MARKOV chains is suggested. Weighty objections against the resulting test statistics were grounds for the planning and performance of a Monte Carlo study. The results of the study demonstrated that the test statistic SS (Cb=0) which is used for the comparison of different MARKOV chains is in fact X2‐distributed. The test statistic SS (F(p) =Xb) for evaluation of the lack of fit of the model also follows a X2‐distribution when a simple MARKOV chain ∼ is used instead of the observed time series ∼ can be determined by simply iterating the original GSK algorithm.
On the Probabilities of Obtaining Negative Estimates of Genetic Variance Components
Authors: Tan W. Y. , Wong S. P. 
Published: April 2007

AbstractThis paper derives the probabilities of obtaining negative estimates of additive and dominance genetic variances when one uses the traditional weighted least square method for estimating genetic variances as given in MATHER and JINKS (1971). The model considered involves P1, P2, F2, B1 (Backcross to P1) and B2 (Backcross to P2). The results are derived under the ordinary assumptions as made in the genetic literatures. It is shown that unless the genetic effects are very large and environmental effects small, the probabilities of obtaining negative estimates of additive and dominance variances are in general quite large.
Testing Hypotheses in the Two‐period Change‐over with Binary Data
Authors: Zimmermann H. , Rahlfs V. 
Published: April 2007

AbstractThe paper proposes a general model for analysizing two‐period change‐over designs with binary data. The model includes tests for carry‐over effects, treatment and period effects in analogy to the well‐known ANOVA‐model for continuous data. Minimum modified χ2‐statistics are derived and formulas for desk calculators are given.
Model Construction and Model Examination on the Basis of Simulated Selection
Authors: Sumpf D. , Dietl G. , Just M. 
Published: April 2007

AbstractBy reason nonlinear relations founded between selection differential and realised selection response we have been made investigations about variants of the genetic‐statistical model, which include this nonlinearity. The variations of the model would not only referred to the postulate pattern of the connection between phenotype, genotype and environment but also enclosed the postulate assumption about the distribution of the variates. In an investigated special case the linear model equation P = G ± e was held, however the distributions of P and G were defined over a limited range in one direction. For P we have defined a modified normal distribution and the distribution of the random vector (G, e) non normal regarded with cov (G, e) ≠ 0, By means of a solution set of an integral equation a density function of the random vector (P, G) has been received, in which the expectation of the selection response of the usual genetic‐statistical model approximate is included as a special case. The genetical parameters has been derived, which result from changed model. However their representation was only possible partially as an integral function. A subsequent paper informs of the examination this mode! variants, which depend on a parameter of the nonlinearity c.
An Unbalanced Two‐way Model With Random Effects Having Unequal Variances
Authors: Hussein M. , Milliken G. A. 
Published: April 2007

AbstractConsider the model yijk=u ± ai ± bi ± cij ± eijk i=1, 2,…, t; j=1, 2,…b; k=1, 2,…,nij where μ is a constant and ai, bi, cij are distributed independently and normally with zero means and variances Δ2 Δ2/bdij and δ2 respectively. It is assumed that di's, and dij's are known (positive) constants (for all i and j). In this paper procedures for estimating the variance components (Δ2, Δ2b and Δ2a) and for testing the hypothesis Hoc:Δ2c/Δ2 = y3 and Hoa:Δ2b/Δ2 = y4 (where y2, y3, and y4, are specified constants) are presented. A generalization for the mixed model case is discussed in the last section.
A New Nonparametric Approach to the Comparison of K Independent Samples of Response Curves
Authors: Lehmacher W. , Wall K. D. 
Published: April 2007

AbstractTwo simultaneous distribution free test procedures to test the homogeneity of K samples of response curves measured at T points of time each are proposed which react upon the shape of the response curve. One procedure is based on the comparison of K T‐tupels of FRIEDMAN‐rank sums, the other on the comparison of K T × T‐incidence tables, which first were introduced by KANNEMANN (1976). The application of the two procedures is illustrated by a numerical example. In the discussion the tests are compared with each other and with concurring tests.
A Simulation Study of Two Paired Sequential Designs by I. D. BROSS
Authors: Page W. F. 
Published: April 2007

AbstractTwo sequential charts designed by I. BROSS, used to analyze serial data for two treatment groups, are studied in this paper. Simulation techniques, rather than theoretical calculations, have been used to determine more complete characteristics of these designs. Of particular interest are the estimates of percentiles of the distribution function of “sample size required to reach a statistical decision”. The distribution parameters of the one‐sided tests, not studied by BROSS, are also given.Es werden 2 sequentielle Pläne von I. BROSS untersucht, die zur Analyse von seriellen Daten für 2 Behandlungsgruppen verwendet werden können. Um diese Pläne umfassender zu charakterisieren, wurde die Simulationstechnik eingesetzt. Von besonderem Interesse waren Abschätzungen von Perzentilen der Verteilungsfunktion der “erforderlichen Stichprobengröße, um eine statistische Entscheidung zu treffen”. Es werden Verteilungsparameter von einseitigen Tests angegeben.
Die Signimaxrotation — ein weiterer Versuch, Faktorenstrukturen interpretationsgünstig zu rotieren
Authors: Schiller W. 
Published: April 2007

AbstractA new method of rotation in factor analysis is introduced, the Signimaxrotation. By this tool the number of the significant factor‐values can be maximated. The basis of its criterion of rotation are the distances between the nonsignificant factor‐values and the nearest limitation of significance and also the number of non‐significant factor‐values. In some examples it is shown that the Signimaxrotation yields results, better than these one of a Varimaxrotation or the visual rotation.Es wird ein neues Rotationsverfahren der Faktoranalyse vorgestellt, die Signimaxrotation. Mit ihr soll die Anzahl der signifikanten Ladungen einer Faktorenstruktur maximiert werden. Grundlagen ihres Rotationskriteriums sind die Abstände der nichtsiguifikanten Ladungen von der nächstgelegenen Signifikanzgrenze sowie die Anzahl der nichtsiguifikanten Ladungen. In Beispielen wird gezeigt, daß die Signimaxrotation bessere Ergebnisse liefert als die Varimaxrotation oder die visuelle Rotation.
Sequential Classification Based on Regression
Authors: KrzyŚAko M. 
Published: April 2007

AbstractLet us consider m general populations π1, …,πm. Each object belonging to these populations is represented by (p ± 1) characteristics x1, x2,…,xp,y. A certain object, which is an element of one of the m general populations π1,…,πm has to be classified into the correct population. It will be assumed that knowledge of the value of the characteristic y would permit its correct classification, but that the observation of this characteristic is expensive, difficult or dangerous, as e.g. in medical applications. y is correlated with a set of p characteristics x1,x2,…,xp, which are observed sequentially. The classification procedure is based on the division of the space of the observed value of characteristics x1,x2,…,xp into nonintersecting areas determined so as to minimize the value of BAYES' risk given by equation (3).
Discriminant Analysis of Biological Shape Profile for Hybridization
Authors: Misra R. K. 
Published: April 2007

AbstractRole of hybridization on growth, nomenclature, speciation, genetics and wildlife management is widely recognised. New situations of hybridization are being discovered and studied yearly (SHORT, 1965). Changes of size make changes of shape and proportions necessary (AlEXANDER, 1971) and for constant efficiency of many body functions (e.g., the locomotory, respiratory and the digestive) systematic size‐correlated alteration of physical shape is an adaptive necessity for many organic relationships (GOULD, 1966). Need for analysing shape for hybridization is therefore obvious. Often an objective of studying hybridization is to estimate the degree of suspected hybrids and thereby specify the distribution of the hybrids in relation to the two parental species, A study of hybridization must recognise the effects of the additive genetic (A) as well as the nonadditive genetic sources (see, e.g., MISRA, 1975a). Discriminant analysis offers a powerful tool for studies of hybrid zones or zones of abrupt phenetic transition, as it is based on the maximisation of differences between biologically meaningful reference samples (ROHWER, 1972). This paper presents a discriminant analysis of biological shape profiles for hybridization based on A and NA sources.
Zur numerischen Auswertung von Schnittflächenverteilungen. IV
Authors: Voss K. 
Published: April 2007

AbstractIn this paper a general integral equation is given for the connection between the size distribution of similar formed objects and the size distribution of their sections with zero thickness. The spherical problem is enclosed in this solution. The integral kernels for six simple polyhedrons are numerically given. The integral geometry is the theoretical basis for this paper, and the computer simulation of the section process is the practical method for the numerical calculation of integral kernels.