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41.
Purpose
We aimed to demonstrate the use of jackknife residuals to take advantage of the longitudinal nature of available growth data in assessing potential biologically implausible values and outliers.Methods
Artificial errors were induced in 5% of length, weight, and head circumference measurements, measured on 1211 participants from the Maternal Vitamin D for Infant Growth (MDIG) trial from birth to 24 months of age. Each child's sex- and age-standardized z-score or raw measurements were regressed as a function of age in child-specific models. Each error responsible for a biologically implausible decrease between a consecutive pair of measurements was identified based on the higher of the two absolute values of jackknife residuals in each pair. In further analyses, outliers were identified as those values beyond fixed cutoffs of the jackknife residuals (e.g., greater than +5 or less than ?5 in primary analyses). Kappa, sensitivity, and specificity were calculated over 1000 simulations to assess the ability of the jackknife residual method to detect induced errors and to compare these methods with the use of conditional growth percentiles and conventional cross-sectional methods.Results
Among the induced errors that resulted in a biologically implausible decrease in measurement between two consecutive values, the jackknife residual method identified the correct value in 84.3%–91.5% of these instances when applied to the sex- and age-standardized z-scores, with kappa values ranging from 0.685 to 0.795. Sensitivity and specificity of the jackknife method were higher than those of the conditional growth percentile method, but specificity was lower than for conventional cross-sectional methods.Conclusions
Using jackknife residuals provides a simple method to identify biologically implausible values and outliers in longitudinal child growth data sets in which each child contributes at least 4 serial measurements. 相似文献42.
Claudio Sartini Peter Tammes Alastair D. Hay Ian Preston Daniel Lasserson Peter H. Whincup S. Goya Wannamethee Richard W. Morris 《Annals of epidemiology》2018,28(1):1-7.e3
Purpose
Living in a cold home increases the risk of dying in winter, especially in older people. However, it is unclear which individual factors predict whether older people are living in cold homes.Methods
Thousand four hundred two men aged 74–95 years from a U.K. population–based study reported difficulties in keeping warm during winter, answering four simple “yes/no” questions. Associations between individual's characteristics and each of the four self-reported measures of cold homes were estimated using logistic regression models. Next, we investigated whether measures of cold homes predict mortality over the subsequent 2.1 years.Results
Manual social class, difficulties making ends meet, and not being married were each associated (P < .05) with each of the four measures of cold homes (adjusted odds ratios ranged from 1.61 to 4.68). Social isolation, poor respiratory health, and grip strength were also associated with reports of cold homes. Hundred twenty-six men died; those who reported the presence of at least three measures cold homes had increased mortality (adjusted hazard ratios 2.85 [95% confidence interval, 1.11–7.30, P = .029]).Conclusions
Older people who find it hard to keep warm in winter, and have an elevated mortality, could be identified using a self-report questionnaire. 相似文献43.
We find ourselves in an era of unprecedented growth in the development and use of so-called “orphan” drugs to treat rare diseases, which are poised to represent more than one-fifth of pharmaceutical expenditures by 2022. This widespread use has been facilitated by legislative and regulatory incentives in both the United States and abroad, yet US payers and health systems have not yet made a concerted effort to understand whether and how rare diseases require special considerations on their part and how to adapt traditional methods of health technology assessment and economic evaluation to accommodate these situations. In this article, we explore the general ethical dilemmas that rare diseases present, steps taken by health technology assessment bodies worldwide to define the level of rarity that would necessitate special measures and the modifications to their assessment and valuation processes needed, and the contextual components for rare-disease evaluation that lie outside of the assessment framework as a guide to US decision makers on constructing a formal and relevant process stateside. 相似文献
44.
Wohter Daniel Quicker Peter Georg Brand Peter Kraus Thomas 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2018,61(6):667-673
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Holzfeuerungen werden in den letzten Jahren aufgrund ihres hohen Anteils am deutschen Feinstaubausstoß in der... 相似文献
45.
Gebauer Corinna Klotz Daniel Springer Skadi 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2018,61(8):952-959
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - In den letzten Jahren konnte der immense Vorteil der Muttermilchernährung für Frühgeborene belegt werden: in Bezug... 相似文献
46.
47.
48.
García Calderín M Torres Lagares D Calles Vázquez C Usón Gargallo J Gutiérrez Pérez JL 《Medicina oral, patología oral y cirugía bucal》2007,12(4):E311-E316
The use of the microscope as a tool for practising Medicine, especially in surgical specialisations, has been established for decades. The microscope was first used in OdontologyDentistry back to the 1970s and 1980s, and was introduced more widely (although it was still far from being in general use) during 1990s. The purpose of this article is to describe the main applications of the microscope in OdontologyDentistry today, as well as providing odontologists and stomatologists, whether specialists or in general practice, with information about microscopic OdontologyDentistry for better patient care. This work also gives particular importance to matters needed to achieve the necessary manual dexterity to work in a magnified operating field using a surgical microscope (SM). 相似文献
49.
Lateral luxation in primary maxillary incisors is a traumatic injury that can lead to darkening of the tooth, pulp necrosis, root resorption, and damage to the permanent teeth. Management of this kind of trauma typically includes pulpectomy or extraction in cases of root resorption. However, in young children, removal of the tooth may be psychological stressing, especially for the parents, while increased mobility can make immediate endodontic treatment difficult to perform. This article outlines a severe palatal luxation on the maxillary right central incisor treated with conservative management in a 2-year-old boy. At the one-year follow-up appointment, the surrounding bone was healthy, the roots displayed physiological resorption, the crowns showed color improvement, and there was no radiographically noticeable damage to the permanent teeth. 相似文献
50.
Braut V Bornstein MM Belser U Buser D 《The International journal of periodontics & restorative dentistry》2011,31(2):125-131
The purpose of this retrospective radiographic study was to analyze the thickness of the facial bone wall at teeth in the anterior maxilla based on cone beam computed tomography (CBCT) images, since this anatomical structure is important for the selection of an appropriate treatment approach in patients undergoing postextraction implant placement. A total of 125 CBCT scans met the inclusion criteria, resulting in a sample size of 498 teeth. The thickness of the facial bone wall in the respective sagittal scans was measured perpendicular to the long axis of the tooth at two locations: at the crest level (4 mm apical to the cementoenamel junction; MP1) and at the middle of the root (MP2). No existing bone wall was found in 25.7% of all teeth at MP1 and in 10.0% at MP2. The majority of the examined teeth exhibited a thin facial bone wall (< 1 mm; 62.9% at MP1, 80.1% at MP2). A thick bone wall (? 1 mm) was found in only 11.4% of all examined teeth at MP1 and 9.8% at MP2. There was a statistically significant decrease in facial bone wall thickness from the first premolars to the central incisors. The facial bone wall in the crestal area of teeth in the anterior maxilla was either missing or thin in roughly 90.0% of patients. Both a missing and thin facial wall require simultaneous contour augmentation at implant placement because of the well-documented bone resorption that occurs at a thin facial bone wall following tooth extraction. Consequently, radiographic analysis of the facial bone wall using CBCT prior to extraction is recommended for selection of the appropriate treatment approach. 相似文献