Resumen. Se presentan los conceptos básicos de muestreo secuencial en sus cinco modalidades,incluyendo muestreo secuencial de tipo estándar, usando solo una densidad crítica, por una precisiónfija, por medio de presencia-ausencia y finalmente de tipo temporal. Se notan un ejemplo real para cadacaso. Se nota y se explica la importancia de la distribución de los datos y los pertinentes ecuaciones. Sepresentan a través de ejemplos reales las ecuaciones para estimar el tamaño óptimo de la muestra paracada uno de las cinco modalidades (...) del muestreo secuencial. Se enfatiza la ventaja económica de estetipo de muestreo.Palabras clave: Distribución de los datos, muestreo secuencial, tamaño óptimo de la muestra. Fundamental concepts of sequential sampling in all its types including standard sequentialsampling, sequential sampling using only one critical density, fixed precision sequential sampling,presence-absence sequential sampling, and time sequential sampling are highlighted. A real caseexample for each of the five sequential samplings is given. The relevance of data distribution forsequential sampling along with corresponding equations is provided and explained. Equations to assessthe optimal sample size for each case are noted and exemplified. The economic advantages of sequentialsampling in stressedKeywords: Data distribution, sample size, sequential sampling. (shrink)

Resumen. Se analizan de forma detallada las bases del muestreo multietápico, la estimación de submuestreo y el muestreo de respuesta aleatoria. Se presentan las ecuaciones pertinentes ejemplificando por medio de casos reales. También se argumentan las situaciones en donde se debe utilizar estos casos específicos. Palabras claves. Caso multietápico, muestreo de respuesta aleatoria, submuestreo.. The basics of multi-stage sampling, sub-sampling and random response sampling are analyzed. Detailed equations regarding these types of sampling are provided. The applications of these types of (...) samplings are denoted by means of real case studies. Keywords. Multi-stage sampling, sub-sampling, random response sampling. (shrink)

Palabras claves. Métodos estadísticos, pruebas de hipótesisResumen. Se presentan de forma simple, breve y por medios de los ejemplos prácticos, los métodos estadísticos que sirven para demostrar la representatividad de una, dos o varias muestras basada en los parámetros poblacionales . Se indican la manera de reducir el tamaño del error experimental para aclarar el efecto significativo de los grupos o muestras bajo el interés . Además, se demuestran la forma de eliminar el efecto de las variables auxiliares o colaterales (...) causante del ruido o error en la estadística . También se nota el uso del modelo ANOVA Anidada para indicar la forma de segmentar la ANOVA en varias partes y de esta manera poder contestar preguntas más complejas. Finalmente, se describen e explican la forma de optimizar los recursos en la conducción de los experimentos y descubrir el efecto de la interacción entre las variables .Keywords. Hypothesis testing, statistical methods. Statistical methods that serve to represent, based upon population parameters of mean and variance, for one, tow or various samples taken from study populations are discussed. Ways to reduce the amount of experimental error in order to clarify the real effect of the treatments are demonstrated . The use of Covariance Analysis to show the pure effect of treatment free from the effect of collateral variables is also indicated. Nested ANOVA that allows division of ANOVA in several parts in order to answer complex questions is described and explained. Finally, the utility of Factorial Analysis for optimization of resource use as well as the illustration of interaction effects are noted and analyzed. (shrink)

In this paper, the authors have detected a new effect in the area of geomagnetism, related to the behavior of a magnetic dipole freely floating on water surface. An experiment is described in the present paper in which a magnetic dipole fixed upon a float placed on non- magnetized water surface undergoes displacement along with reorientation caused by fine structure of the earth's magnetic field. This fact can probably be explained by secular decrease of the earth's major dipole moment. Further, (...) a detailed study of the phenomenon may create interesting premises for its practical use, particularly for the analysis of fine structure of geomagnetic field and its time-dependent anomalies. A strange behavior of some sea fish species prior to strong earthquakes may be explained if the fish are assumed as 'live magnetic dipoles'. (shrink)

BackgroundPublic health scholars have long called for preparedness to help better negotiate ethical issues that emerge during public health emergencies. In this paper we argue that the concept of ethical preparedness has much to offer other areas of health beyond pandemic emergencies, particularly in areas where rapid technological developments have the potential to transform aspects of health research and care, as well as the relationship between them. We do this by viewing the ethical decision-making process as a behaviour, and conceptualising (...) ethical preparedness as providing a health research/care setting that can facilitate the promotion of this behaviour. We draw on an implementation science and behaviour change model, COM-B, to demonstrate that to be ethically prepared requires having the capability, opportunity, and motivation to work in an ethically prepared way.MethodsWe use two case examples from our empirical research—one pandemic and one non-pandemic related—to illustrate how our conceptualisation of ethical preparedness can be applied in practice. The first case study was of the UK NHSX COVID-19 contact tracing application case study involved eight in-depth interviews with people involved with the development/governance of this application. The second case involved a complex case regarding familial communication discussed at the UK Genethics Forum. We used deductive qualitative analysis based on the COM-B model categories to analyse the transcripbed data from each case study.ResultsOur analysis highlighted that being ethically prepared needs to go beyond merely equipping health professionals with skills and knowledge, or providing research governance actors with ethical principles and/or frameworks. To allow or support these different actors to utilise their skills and knowledge, a focus on the physical and social opportunity is important, as is a better understanding the role of motivation.ConclusionsTo understand ethical preparedness, we need to view the process of ethical decision-making as a behaviour. We have provided insight into the specific factors that are needed to promote this behaviour—using examples from both in the pandemic context as well as in areas of health research and medicine where there have been rapid technological developments. This offers a useful starting point for further conceptual work around the notion of being ethically prepared. (shrink)

Objective To determine the attitudes of Egyptian patients regarding their participation in research and with the collection, storage and future use of blood samples for research purposes. Design Cross-sectional survey. Study population Adult Egyptian patients (n=600) at rural and urban hospitals and clinics. Results Less than half of the study population (44.3%) felt that informed consent forms should provide research participants the option to have their blood samples stored for future research. Of these participants, 39.9% thought that consent forms should (...) include the option that future research be restricted to the illness being studied. A slight majority (66.2%) would donate their samples for future genetic research. Respondents were more favourable towards having their blood samples exported to other Arab countries (62.0%) compared with countries in Europe (41.8%, p<0.001) and to the USA (37.2%, p<0.001). Conclusions This study shows that many individuals do not favour the donation of a blood sample for future research. Of those who do approve of such future research, many favour a consent model that includes an option restricting the future research to the illness being studied. Also, many Egyptians were hesitant to have their blood samples donated for genetic research or exported out of the Arab region to the USA and European countries. Further qualitative research should be performed to determine the underlying reasons for many of our results. (shrink)

Background: Older, frail patients with multimorbidity are at an especially high risk for disease severity and death from COVID-19. The social restrictions proved challenging for the residents, their relatives, and the care staff. While these restrictions clearly impacted daily life in Norwegian nursing homes, knowledge about how the pandemic influenced nursing practice is sparse. Aim: The aim of the study was to illuminate ethical difficult situations experienced by Norwegian nurses working in nursing homes during the COVID-19 pandemic. Research design and (...) participants: The research design involved semistructured individual interviews conducted with 15 nurses working in 8 nursing homes in 3 health regions in Norway, within both urban and rural areas. Ethical considerations: Oral and written information about the study was provided before the participants gave their written consent. The transcribed interviews were de-identified. The study was approved by the Norwegian Centre for Research Data. Findings: Four ethical difficult situations were identified: (a) turning the nursing home into a prison; (b) using medication to maintain peace and order; (c) being left alone with the responsibility; and (d) s. impact on decision-making. Conclusions: The nurses’ ethical challenges were intertwined with external factors, such as national and local guidelines, and the nurses’ own internalized factors, which were connected to their subjective professionality. This duality inflicted emotional distress and gave nurses few opportunities to perform nursing in a professionally sound and safe manner. (shrink)