Search results for "Small sample"
showing 10 items of 32 documents
Reliability results of straylight measurements using the C-Quant
2008
Purpose Assessment of repeatability and reproducibility of straylight measures with the C-Quant straylightmeter (Oculus AG, Germany), effect of age on reliability measures and correlation of measures determined with new methods of scatter determination. Methods Results from different studies will be presented. For repeatability assessment, 20 eyes (age 26.9±2.7 years) were examined with the C-Quant, taking 10 consecutive readings. 5 subjects were also examined on 5 consecutive days to assess reproducibility. Repeated measures from 84 subjects, age range 19-86 years, were analysed to assess the effect of patient’s age. Software was developed to quantify scatter from centroid patterns obtaine…
A Comparison of Formulae for Calculating Cost-Efficient Sample Sizes of Case-Control Studies with an Internal Validation Scheme
2000
When a case-control study is planned to include an internal validation study, the sample size of the study and the proportion of validated observations has to be calculated. There are a variety of alternative methods to accomplish this. In this article some possible procedures will be compared in order to clarify whether considerable differences in the suggested optimal designs occur, dependent on the used method.
Visualization in comparative music research
2007
Computational analysis of large musical corpora provides an approach that overcomes some of the limitations of manual analysis related to small sample sizes and subjectivity. The present paper aims to provide an overview of the computational approach to music research. It discusses the issues of music representation, musical feature extraction, digital music collections, and data mining techniques. Moreover, it provides examples of visualization of large musical collections.
Can Applications Designed to Evaluate Visual Function Be Used in Different iPads?
2018
SIGNIFICANCE: Apple devices could be suitable for vision tests, provided that the test has been correctly adapted to the device, after considering the spatial and colorimetric characterization of the screen. PURPOSE: The majority of vision applications has not been developed by vision or colorimetry experts and suffers from conceptual and design errors that may lead average users to an erroneous assessment of their visual capabilities. The reliability of vision tests depends on the accurate generation of the necessary visual stimuli in a particular device. Our aim was to ascertain whether a given color test, designed for a colorimetrically characterized device, might be used in another simi…
Optimal sample allocation conditioned on a small area model, estimator, and auxiliary data
2018
We have studied optimal sample allocation, associated with small area estimation, when the objective is to obtain as accurate estimates as possible, for the population and for the subpopulations, called as areas here. It is a question of a two-level optimization problem. The basic premise is composed of planned areas, stratified sampling, and small overall sample size predetermined by restricted time and budget resources. Low sample sizes are common in market surveys. During this thesis, we have developed new allocation methods, based on a small area model, estimator, and auxiliary data. The final method, the three-term Pareto allocation, is based on the three terms of the mean-squared erro…
Current understanding of genetic polymorphisms as biomarkers for risk of biological complications in implantology
2018
Background In the last decade, multiple studies have been published that analyze the relationship between the risk of experiencing biological complications with implants and the presence of certain types of genetic polymorphisms. In the present report, we analyze the controversies that have arisen from this important area of investigation and synthesize the most prominent aspects of knowledge related to this possible etiopathogenic relationship. Material and methods For this review, the biomedical databases PubMed-Medline, SciELO, and DOAJ were used. Different search strategies were employed, from which 298 articles initially emerged. After refinement of the search, 55 articles published be…
Diagnostic and prognostic value of H-FABP in acute coronary syndrome: Still evidence to bring
2018
Abstract The assessment of chest pain patients presenting to the emergency area (EA) is still a clinical challenge, as the majority of patients are not diagnosed with acute coronary syndrome (ACS). New generation high sensitivity c-Tn (hs-cTn) assays have showed better performances compared to the standard c-Tn. However, hs-Tn still presents some limitations. Hence, novel, early biomarkers are needed in this setting. Among all, heart-type fatty acid binding protein (H-FABP) has been largely investigated. This article reviews the studies evaluating H-FABP performance in diagnosing acute myocardial infarction (AMI) and stratifying chest pain patients by risk. H-FABP optimal performances in AC…
Air pollution and airport apron workers: A neglected occupational setting in epidemiological research.
2020
Abstract Introduction Airport apron workers are occupationally exposed to jet exhaust and major concern is related to the exposure to ultrafine particles (UFP) from aircrafts. To date, little attention has been given to occupational exposures to aircraft-related UFP, although aircraft engines have high emissions of ultrafine particles, which are orders of magnitude higher than residential exposure. UFP could possibly contribute to the development of cancer, heart disease, mental illness, and respiratory symptoms. In addition to particulate matter, apron workers are exposed to other polluting substances associated with vehicles, aircraft exhaust or direct fuel emissions. Methods We performed…
World Health Organization guidelines for cancer pain: a reappraisal
2005
Pain is a prevalent symptom experienced by at least 30% ofpatients undergoing an oncological treatment for metastaticdisease and by more than 70% of advanced cancer patients[1]. In 1986 the World Health Organization [2] published a setof guidelines for cancer pain management based on the three-step analgesic ladder [2]. The main aim of WHO guidelienswas to legitimize the prescribing of strong opioids, arisingfrom evidence of poor management of cancer pain, due toreluctance of health care professionals, institutions, and gov-ernment to use opioids because of fears of addition, toleranceand illegal abuse.Its application is reported to achieve satisfactory pain reliefin up to 90% of patients w…
Randomized controlled study of a mandibular advancement appliance for the treatment of obstructive sleep apnea in children: A pilot study
2015
Background: The current limited evidence may be suggestive that mandibular advancement appliance (MAAs) result in improvements in AHI scores, but it is not possible to conclude that MAAs are effective to treat paediatric OSA. There are significant weaknesses in the existing evidence due primarily to absence of control groups, small sample sizes, lack of randomization and short-term results. Aim: the objective of the present study was to evaluate MAAs in children with OSA. Material and Methods: Children presenting an apnea-hypopnea index (AHI) greater than or equal to one event per hour were considered to be apneic. This group of children with AHI greater than or equal to one was randomly di…