bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rationale and design of the Optimal Macro-Nutrient Intake Heart Trial to Prevent Heart Disease (OMNI-Heart)
Authors: Carey Vincent J , Bishop Louise , Charleston Jeanne , Conlin Paul , Erlinger Tate , Laranjo Nancy , McCarron Phyllis , Miller Edgar , Rosner Bernard , Swain Janis , Sacks Frank M , Appel Lawrence J 
Published: December 2005

Background The DASH (Dietary Approaches to Stop Hypertension) diet is a carbohydrate-rich, reduced-fat diet that lowers blood pressure (BP) and LDL-cholesterol. Whether partial replacement of some carbohydrate (C) with either protein (P) or unsaturated fat (U) can further improve these and other cardiovascular (CVD) risk factors is unknown. Methods OmniHeart is a randomized, three-period, crossover feeding study designed to compare the effects on BP and blood lipids of a carbohydrate-rich diet (CARB, similar to the DASH diet) with a diet rich in protein (PROT, predominantly from nonmeat sources) and a diet rich in unsaturated fat (UNSAT, predominantly monounsaturated). Throughout feeding (run in and the three intervention periods), participants are provided with all of their meals that meet the nutrient profile of their assigned diet. Calorie intake is adjusted to maintain weight. The target sample size is 160 (50% African-American). Participants are adults, aged 30 or older, with prehypertension or Stage 1 hypertension (systolic BP 120–159 or diastolic BP 80–99 mmHg). The primary outcome variables are systolic BP and LDL-cholesterol. Secondary outcomes are diastolic BP, HDL-cholesterol, and triglycerides. Other outcome variables are total cholesterol, apolipoproteins VLDL-apoB, VLDL-apoCIII, apolipoprotein B, non-HDL cholesterol, and lipoprotein(a), and insulin resistance, as measured by Homeostasis Model Assessment (HOMA). Conclusions OMNI-Heart should advance our fundamental knowledge of the effects of diet on both traditional and emerging risk factors, and, in the process, guide policy makers, health care providers and the general public on the relative benefits of carbohydrate, protein, and unsaturated fat as a means to reduce CVD risk.
Non-linearity of Parkinson’s disease progression: implications for sample size calculations in clinical trials
Authors: Guimaraes Paulo , Kieburtz Karl , Goetz Christopher G , Elm Jordan J , Palesch Yuko Y , Huang Peng , Ravina Bernard , Tanner Caroline M , Tilley Barbara C 
Published: December 2005

Background Estimation of sample size for long-term studies of neuroprotection in Parkinson’s disease requires information on expected clinical decline. Values may be obtained by analyzing existing long-term data sets or by prediction models of clinical decline applied to available data from shorter-term trials. The most commonly used measure to track clinical decline is the Unified Parkinson’s Disease Rating Scale (UPDRS) but this measure is also affected by symptomatic therapy. Models can help better understand behavior of the UPDRS after initiation of symptomatic therapy when scores will improve and eventually start deteriorating again. Purpose To understand how UPDRS scores progress after initiation of symptomatic therapy and how this progression impacts sample size calculations. Methods We developed a non-linear model of UPDRS after introduction of symptomatic therapy. The model is specified as a non-linear mixed effects model and is applied to three different data sets from clinical trials. The model is then used to produce estimates for the change in UPDRS and its associated variance for a period of up to five years of follow-up. The estimates produced by the model serve as the basis for sample-size calculations for different lengths of follow-up (one through five years) and for different values of clinically meaningful change in UPDRS. Results Despite differences in the short-term benefit of the dopaminergic drugs, after a period of approximately six months UPDRS scores progress linearly at an estimated rate of approximately three points a year. The sample size that is required for a clinical trial where the baseline coincides with initiation of symptomatic therapy is very large. On the other hand, if baseline is set at six months after initiation of symptomatic therapy then the sample size required decreases with length of follow-up. Limitations Model specification and estimation is based on a set of simplifying assumptions regarding the progression of individual level UPDRS scores. Conclusions Sample size calculations based on these estimates indicate a substantial reduction in sample size if patients are required to be on symptomatic treatment for a period of time before being randomized to a neuroprotective trial.
Group sequential methods for cluster randomization trials with binary outcomes
Authors: Zou Guang Yong , Donner Allan , Klar Neil 
Published: December 2005

Background Cluster randomization trials in which intact social units are randomly assigned to different intervention groups have become very popular in recent years, particularly for the evaluation of innovations in the delivery of health care. An extensive literature dealing with the associated methodological challenges has also appeared. Although the monitoring of such trials using formal stopping rules is clearly indicated when the outcomes are irreversible and individual-level data are available sequentially, simple and reliable statistical methods that may be used for this purpose are currently not available. Purpose To investigate the validity of standard group sequential methods when applied to cluster randomization trials having binary outcomes. Methods The large sample distributions for each of five test statistics computed from sequentially accumulated data are derived. A simulation study is performed to evaluate the finite sample properties of these statistics when applied to the interim analysis of cluster randomization trials. Data from the World Health Organization antenatal care trial [1] are used to illustrate the methods. Results Each of the joint distributions is shown to be characterized by a covariance structure that asymptotically satisfies an independent increments structure, a foundation that simplifies group sequential methods [2]. The simulation study reveals that four of the five test statistics evaluated provide satisfactory performance with as few as 10 clusters allocated to each of two interventions. Limitations The applicability of our results to effect estimation following a group sequential cluster randomization trial is not investigated, although a theoretical foundation which may be used for this purpose is presented. Conclusions Standard group sequential methods can be applied to cluster randomization trials when interim analyses are warranted.
Nonignorable censoring in randomized clinical trials
Authors: Zhang Jiameng , Heitjan Daniel F 
Published: December 2005

Background In a clinical trial, survival may be censored by the end of the study, especially for subjects who enter later in the enrollment period. If there is a trend toward better survival over time then longer survivors experience shorter censoring times (heavier censoring). In such a case, the censoring and survival times are correlated, and thus the censoring is nonignorable in the sense that standard survival models that assume independent censoring could yield incorrect inferences. We will demonstrate a graphical method for analyzing sensitivity of estimates of survival model parameters to small departures from nonignorable censoring. Methods We assume a parametric model of survival together with a scaled beta model for the censoring process that incorporates the dependence of censoring time on survival time. We assess sensitivity using an index of local sensitivity to nonignorability (Troxel et al. [1]). High sensitivity indicates a large impact of nonignorable censoring on the parameter of interest and a need for additional modeling. Results A simulation study shows that the approach is valid for practical use. We apply our method to a clinical trial evaluating the survival benefit of a surgically implanted left ventricular assist device in subjects with end-stage heart failure. Sensitivity is somewhat larger in estimates of the mean survival in the device arm, where survival is better and the fraction censored is therefore larger. The degree of nonignorability required to substantially affect estimates is larger than seems plausible, however. Conclusions Our results illustrate how one can apply sensitivity analysis to evaluate the reliability of survival parameter estimates in a clinical trial.
The 2003 Bam Urban Earthquake: A Predictable Seismotectonic Pattern along the Western Margin of the Rigid Lut Block, Southeast Iran
Authors: Berberian Manuel 
Published: December 2005

“…King Ardeshir Babakan Sassanid [r. AD 224-241], by conquering Kerman and Bam, killed the ‘Kerm-e-Haftvad’ [the Haftvad Silk Worm] at the Bam Citadel. The gigantic worm burst with a big bang noise, which rocked the area, completely destroyed the Bam Citadel, and killed most of the inhabitants of the Citadel. King Ardeshir put an end to the rule of governor Haftvad, built the new village of Kolalan/Kojaran [Kurzan; the old Deh Shotor quarter in west Bam], and brought the ‘seven sacred fires of Bahram’ to the new village…” [Book of Deeds of Ardashir Pabagan 1878 (English Tr., original version ca. AD 272); Tabari 915; Ferdowsi Tusi 1010; & Mostaufi Qazvini 1340. The entire episode rests on the rationalization of historical events of unknown nature, and perhaps the legendary element could be a possible, mixed metaphoric reference to a ‘destructive earthquake’ or even a ‘conquering battle’ against the ancient city of Bam and its Parthian governor, Haftvad!] The impact of the Bam urban earthquake of 26 December 2003 ( Mw 6.6) was far more devastating than that which would be expected from a moderate-magnitude earthquake. The event followed a predictable geological/seismological pattern of a specially clustered sequence of medium- to large- magnitude earthquakes on tectonically related active faults in a region with historic slip deficits along the western margin of the rigid Lut block. The earthquake was accompanied by the coseismic rupture of sub-parallel strike-slip faults in a zone revealing a pattern of temporal clustering of seismicity, loading of adjacent faults, and a southwards progressing trend of earthquakes from the Kuh Banan to the Gowk and the Bam fault systems. As with the Agadir, Morocco, earthquake of 1960, and the great Tangshan, China, earthquake of 1976, the Bam urban earthquake painfully demonstrated the growing vulnerability of a city built on or adjacent to a seismic fault, unprepared to be tested by the severe ground motion triggered by a medium magnitude earthquake. The absence of historical seismic records regarding the occurrence of earthquakes in the region or the lengthy time spans between such disasters has been erroneously interpreted as a lack of any potential threat for the last 2,500 years in the city of Bam.
Patterns of Care in Early-Stage Breast Cancer Survivors in the First Year After Cessation of Active Treatment
Authors: Mandelblatt Jeanne S. , Lawrence William F. , Cullen Jennifer , Stanton Annette L. , Krupnick Janice L. , Kwan Lorna , Ganz Patricia A. 
Published: December 2005

PurposePatterns of health care use have not been well described for breast cancer survivors. The purpose of this study was to describe the health service use in a survivor cohort.Patients and MethodsWomen with stage I or II breast cancer were recruited (n = 558) after primary treatment for a multicenter, randomized trial of psychoeducational interventions for facilitating transition to survivorship; 418 women completed the study. Participants completed calendar diaries detailing health care use for 1 year after treatment. Services were coded using Current Procedural Terminology–Fourth Edition codes; costs were estimated using year 2000 Medicare reimbursements.ResultsHealth care use diary data were available for 391 women (70% of the sample). On average, these survivors reported 30 episodes of health service use in the year after treatment. Total annual costs of care averaged more than $1,800 per survivor; medical office visits were the major component of costs. Type of cancer treatment, depression, and physical function and comorbid illness were independent predictors of the costs of services. There were geographic variations in initial local treatment patterns and in post-treatment costs. Notably, all women should have received surveillance mammography in the time period, but only 61.9% did so; the odds of mammogram receipt were higher for women who had a lumpectomy (v mastectomy) and women who were white (v nonwhite).ConclusionUse of health services is frequent and intensive in the first year after treatment for breast cancer. Despite frequent contact with the health care system, there is room for improvement in providing guideline-suggested surveillance mammography for survivors.
Factors Related to Underuse of Surveillance Mammography Among Breast Cancer Survivors
Authors: Keating Nancy L. , Landrum Mary Beth , Guadagnoli Edward , Winer Eric P. , Ayanian John Z. 
Published: December 2005

Purpose Many older breast cancer survivors do not undergo annual mammography despite guideline recommendations. We identified factors associated with underuse of surveillance mammography and examined whether variation was explained by differences in follow-up care. Patients and Methods We used Surveillance, Epidemiology, and End Results-Medicare data to identify a population-based sample of 44,511 women fee-for-service Medicare enrollees aged ≥ 65 years who were diagnosed with stage I or II breast cancer in 1992 to 1999 who underwent primary surgical therapy. We assessed factors associated with mammography during months 7 to 18, 19 to 30, and 31 to 42 after breast cancer diagnosis using repeated-measures logistic regression; and we examined whether follow-up care with providers of various specialties explained variation in mammography use. Results Only three quarters of women (77.6%) underwent mammography during months 7 to 18 after diagnosis, and only 56.7% had mammography yearly over 3 years. In multivariable analyses, women who were older, black, unmarried, and living in certain regions were less likely than other women to undergo surveillance mammography (all P < .05). Patients with more visits and patients who continued to see a medical oncologist, radiation oncologist, or surgeon were most likely to have mammograms (P < .001); however, adjusting for visits with providers did not explain the lower mammography rates based on age, race, marital status, and geographic region. Conclusion Many elderly breast cancer survivors do not undergo annual surveillance mammography, particularly women who are older, black, and unmarried, and this underuse was not explained by access to follow-up care. New strategies are needed to increase use of surveillance mammography and decrease variations based on nonclinical factors that are likely unrelated to appropriateness of medical care.
Comparable Long-Term Survival After Unrelated and HLA-Matched Sibling Donor Hematopoietic Stem Cell Transplantations for Acute Leukemia in Children Younger Than 18 Months
Authors: Eapen Mary , Rubinstein Pablo , Zhang Mei-Jie , Camitta Bruce M. , Stevens Cladd , Cairo Mitchell S. , Davies Stella M. , Doyle John J. , Kurtzberg Joanne , Pulsipher Michael A. , Ortega Juan J. , Scaradavou Andromachi , Horowitz Mary M. , Wagner John E. 
Published: December 2005

Purpose To describe outcomes after unrelated donor stem cell transplantation (HCT) in children (< 18 months at diagnosis) with acute leukemia and compare these with outcomes after human leukocyte antigen (HLA)-matched sibling donor HCT. Patients and Methods We compared the results of unrelated donor HCT with bone marrow (n = 85) or cord blood grafts (n = 81) and HLA-matched sibling donor HCT with bone marrow grafts (n = 101) for acute myeloid or acute lymphoblastic leukemia using Cox proportional hazards models. Unrelated donor HCT recipients were younger, more likely to have MLL gene rearrangement, to have advanced leukemia, and to receive irradiation before HCT. Results Treatment-related mortality rates were 6%, 15%, and 31% after matched sibling, unrelated donor bone marrow, and cord blood HCT, respectively. Risks of relapse, overall and leukemia-free survival were significantly associated with disease status at transplantation. Though leukemia recurrence was lowest after unrelated donor HCT in first clinical remission (CR), overall survival, and leukemia-free survival rates were similar after matched sibling and unrelated donor HCT, after adjustment for disease status. Relapse, overall and leukemia-free survival did not differ by graft type (bone marrow v cord blood) or type of leukemia. Three-year probabilities of leukemia-free survival were 49% and 54% after HLA-matched sibling and unrelated donor transplantation in first CR, respectively. Corresponding rates for those with advanced leukemia were 20% and 30%. Conclusion Unrelated donor HCT should be considered for infants with acute leukemia in first CR using the same eligibility criteria as are currently used for those with HLA matched sibling donors.
Unconventional Anticancer Agents: A Systematic Review of Clinical Trials
Authors: Vickers Andrew J. , Kuo Joyce , Cassileth Barrie R. 
Published: December 2005

Purpose A substantial number of cancer patients turn to treatments other than those recommended by mainstream oncologists in an effort to sustain tumor remission or halt the spread of cancer. These unconventional approaches include botanicals, high-dose nutritional supplementation, off-label pharmaceuticals, and animal products. The objective of this study was to review systematically the methodologies applied in clinical trials of unconventional treatments specifically for cancer. Methods MEDLINE 1966 to 2005 was searched using approximately 200 different medical subject heading terms (eg, alternative medicine) and free text words (eg, laetrile). We sought prospective clinical trials of unconventional treatments in cancer patients, excluding studies with only symptom control or nonclinical (eg, immune) end points. Trial data were extracted by two reviewers using a standardized protocol. Results We identified 14,735 articles, of which 214, describing 198 different clinical trials, were included. Twenty trials were phase I, three were phase I and II, 70 were phase II, and 105 were phase III. Approximately half of the trials investigated fungal products, 20% investigated other botanicals, 10% investigated vitamins and supplements, and 10% investigated off-label pharmaceuticals. Only eight of the phase I trials were dose-finding trials, and a mere 20% of phase II trials reported a statistical design. Of the 27 different agents tested in phase III, only one agent had a prior dose-finding trial, and only for three agents was the definitive study initiated after the publication of phase II data. Conclusion Unconventional cancer treatments have not been subject to appropriate early-phase trial development. Future research on unconventional therapies should involve dose-finding and phase II studies to determine the suitability of definitive trials.
A New Honeycomb Assemblage of a Trisdithiolene Vanadium(IV) Complex, (PPh4)2[V(dbddto)3](C6H4Cl2)(hexane)0.5
Authors: Okubo Takashi , Maeda Ryoko , Kondo Mitsuru , Mitani Tadaoki , Kitagawa Susumu 
Published: January 2006

Abstract
A new trisdithiolene vanadium(IV) complex has been synthesized and characterized. The enantiomeric anion units, [V(dbddto)3]2−, are packed so closely that the sulfur-rich planar ligands stack to form a honeycomb sheet structure, resulting in the creation of large cavities (12 × 5.5 Å) for guests. The magnetic susceptibilities show an existence of antiferromagnetic interaction in spite of the large interatomic separation of the vanadium ions (V···V distance = 11.069 Å (av.)), associated with the interaction between the stacking ligand pathway in the honeycomb sheet.
Emergency Dental Clinic Patients in South Devon, their Anxiety Levels, Expressed Demand for Treatment under Sedation and Suitability for Management under Sedation
Authors: Baker Robert A , Farrer Susan , Perkins Vanessa J , Sanders Hilary 
Published: December 2005

Objective To assess the anxiety levels of patients attending two salaried dental service emergency clinics, their expressed demand for treatment under sedation, and their medical suitability for dental sedation. Design A questionnaire survey, incorporating the Modified Dental Anxiety Scale (MDAS) and assessment of American Society of Anesthesiologists’ (ASA) physical status classification, of all adult patients attending two emergency dental clinics in Torquay and Newton Abbot. Results 513 patients returned questionnaires. Only five declined to take part in the study. The mean MDAS for patients attending the two emergency dental clinics was 14.09 (SD 6.04) and 41.9% of patients were classified as dentally anxious (MDAS >15). A preference for treatment under sedation was expressed by 56.3%, of all patients, of whom 50.5% were classified as ASA 1 (without health problems) and would have been suitable for sedation in primary dental care. Conclusions The reported dental anxiety levels of patients attending the two emergency dental clinics were found to be much higher than those found by previous studies in general dental practice and at dental school emergency clinics. There was a high expressed demand for treatment under sedation. Further studies are needed to assess the levels of dental anxiety seen at other dental emergency clinics and a health needs assessment to determine need as opposed to expressed demand.
A Study of the Prescription of Radiographs for Children by a Group of General Dental Practitioners in the South West of England
Authors: Patel Brijesh R , Jones Adam , Crawford Peter JM 
Published: December 2005

Objective This study aimed to assess the familiarity of general dental practitioners (GDPs) in the South West of England with the guidelines in the first edition of the then Faculty of General Dental Practitioners (UK) ‘good practice guidelines’ publication Selection Criteria for Dental Radiography (henceforth referred to as ‘the guidelines’) by studying the prescription of radiographs for children in two case scenarios. Method A single mailshot of questionnaires containing questions relating to the guidelines and the two case scenarios was sent to 136 GDPs in the South West of England. Their recommendations for the prescription of radiographs for the children in the two scenarios were then compared with the guidelines. Results There was a 60% response rate. Of the respondents, 48% reported that they had access to the guidelines. Of those who responded to the question, 66% said that they found the guidelines easy to use. Seventy per cent of respondents reported that they preferred the concept of guidelines to that of protocols. The results from the case scenarios revealed an under-prescription of radiographs for patients presenting with developmental problems or trauma when compared to the recommendations in the guidelines. There was good correlation for the prescription of radiographs for caries but little consensus on radiographic review times. Conclusions The study highlighted (a) areas within the guidelines that require further clarification and research and (b) that in the group studied half did not have access to the guidelines.