Replicability of simulation studies for the investigation of statistical methods: The RepliSims project

Results of simulation studies evaluating the performance of statistical methods can have a major impact on the way empirical research is implemented. However, so far there is limited evidence of the replicability of simulation studies. Eight highly cited statistical simulation studies were selected, and their replicability was assessed by teams of replicators with formal training in quantitative methodology. The teams used information in the original publications to write simulation code with the aim of replicating the results. The primary outcome was to determine the feasibility of replicability based on reported information in the original publications and supplementary materials. Replicasility varied greatly: some original studies provided detailed information leading to almost perfect replication of results, whereas other studies did not provide enough information to implement any of the reported simulations. Factors facilitating replication included availability of code, detailed reporting or visualization of data-generating procedures and methods, and replicator expertise. Replicability of statistical simulation studies was mainly impeded by lack of information and sustainability of information sources. We encourage researchers publishing simulation studies to transparently report all relevant implementation details either in the research paper itself or in easily accessible supplementary material and to make their simulation code publicly available using permanent links

ECHO PROPERTIES OF BGO AND CdS

A brief discussion is given of the theory of echo generation in insulators and semiconductors. For semiconductors it is shown that ω, 2ω echo generation may occur without dc-field present. In this case the echo amplitude is directly proportional to the electronic conductivity and the applied fields. Experiments in CdS support the predictions. From measurements on BGO it is concluded that interactions with vacancies which is responsible for strong acoustic attenuation at low temperatures, does not contribute in the echo generation

Clinical practices to promote sleep in the ICU:A multinational survey

Purpose: To describe sleep assessment and strategies to promote sleep in adult ICUs in ten countries. Methods: Multicenter, self-administered survey sent to nurse managers. Results: Response rate was 66% with 522 ICUs providing data. ‘Lying quietly with closed eyes’ was the characteristic most frequently perceived as indicative of sleep by >60% of responding ICUs in all countries except Italy. Few ICUs (9%) had a protocol for sleep management or used sleep questionnaires (1%). Compared to ICUs in Northern Europe, those in central Europe were more likely to have a sleep promoting protocol (p < 0.001), and to want to implement a protocol (p < 0.001). In >80% of responding ICUs, the most common non-pharmacological sleep-promoting interventions were reducing ICU staff noise, light, and nurse interventions at night; only 18% used earplugs frequently. Approximately 50% of ICUs reported sleep medication selection and assessment of effect were performed by physicians and nurses collaboratively. A multivariable model identified perceived nursing influence on sleep decision-making was associated with asking patients or family about sleep preferences (p = 0.004). Conclusions: We found variation in sleep promotion interventions across European regions with few ICUs using sleep assessment questionnaires or sleep promoting protocols. However, many ICUs perceive implementation of sleep protocols important, particularly those in central Europe

Clinical practices to promote sleep in the ICU: A multinational survey

Purpose: To describe sleep assessment and strategies to promote sleep in adult ICUs in ten countries. Methods: Multicenter, self-administered survey sent to nurse managers. Results: Response rate was 66% with 522 ICUs providing data. ‘Lying quietly with closed eyes’ was the characteristic most frequently perceived as indicative of sleep by &gt;60% of responding ICUs in all countries except Italy. Few ICUs (9%) had a protocol for sleep management or used sleep questionnaires (1%). Compared to ICUs in Northern Europe, those in central Europe were more likely to have a sleep promoting protocol (p &lt; 0.001), and to want to implement a protocol (p &lt; 0.001). In &gt;80% of responding ICUs, the most common non-pharmacological sleep-promoting interventions were reducing ICU staff noise, light, and nurse interventions at night; only 18% used earplugs frequently. Approximately 50% of ICUs reported sleep medication selection and assessment of effect were performed by physicians and nurses collaboratively. A multivariable model identified perceived nursing influence on sleep decision-making was associated with asking patients or family about sleep preferences (p = 0.004). Conclusions: We found variation in sleep promotion interventions across European regions with few ICUs using sleep assessment questionnaires or sleep promoting protocols. However, many ICUs perceive implementation of sleep protocols important, particularly those in central Europe. © 2018 Elsevier Lt