Young People's Experiences of Participation in Clinical Trials: Reasons for Taking Part

Given the lack of knowledge about safety and efficacy of many treatments for children, pediatric clinical trials are important, but recruitment for pediatric research is difficult. Little is known about children's perspective on participating in trials. The purpose of this study was to understand the experiences and motivations of young people who took part in clinical trials. This is a qualitative interview study of 25 young people aged 10–23 who were invited to take part in clinical trials. Interviews were audio or video recorded and analyzed using framework analysis. Young peoples' motivations were both personal benefit and helping others. Both incentives appeared to be more complex than expected. We introduce the terms “network of exchange” and “intergenerational solidarity” to describe these motivations. To improve recruitment, professionals should be more open about research opportunities, provide better information, and give young people feedback after the trial has ended.     

Lack of free choice reveals the cost of multiple-target search within and across feature dimensions

Having to look for multiple targets typically results in switch costs. However, using a gaze-contingent eyetracking paradigm with multiple color-defined targets, we have recently shown that the emergence of switch costs depends on whether observers can choose a target or a target is being imposed upon them. Here, using a similar paradigm, we tested whether these findings generalize to the situation in which targets are specified across different feature dimensions. We instructed participants to simultaneously search for, and then fixate, either of two possible targets presented among distractors. The targets were defined as either two colors, two shapes, or one color and one shape. In one condition, only one of the two targets was available in each display, so that the choice was imposed. In the other condition, both targets would be present in each display, which gave observers free choice over what to search for. Consistent with our earlier findings, switch costs emerged when targets were imposed, whereas no switch costs emerged when target selection was free, irrespective of the dimension in which the targets were defined. The results are consistent with the operation of different modes of control in multiple-target search, with switch costs emerging whenever reactive control is required and being reduced or absent when displays allow for proactive control.     

Failure mechanism in porous materials under compression: crackling noise in mesoporous SiO2

The failure mechanism of porous materials under uniaxial stress has been investigated experimentally. Microporous SiO₂, Vycor, has been subjected to slowly increasing compressive uniaxial stress with stress rates between 0.2 and 12.2?kPa/s. With increasing stress the strain changes stepwise with acoustic emission correlated with each volume collapse. The acoustic emission followed the characteristics of ‘crackling noise’ with a power law distribution over an exceptionally large interval of 6 decades at the slowest stress rate. The power law exponent is ?1.39. Possible applications in mining industry and others are discussed.     

Does maternal prenatal stress adversely affect the child's learning and memory at age six?

Prenatal maternal stress has been shown to affect postnatal development in animals and humans. In animals, the morphology and function of the offspring's hippocampus is negatively affected by prenatal maternal stress. The present study prospectively investigated the influence of prenatal maternal stress on learning and memory of 112 children (50 boys, 62 girls, Age: M=6.7 years, SD=8.4 months), with the Test of Memory and Learning (TOMAL). Maternal stress levels were determined three times during pregnancy by self-report questionnaires. Furthermore, maternal saliva cortisol samples were used as a measure of hypothalamus-pituitary-adrenal axis functioning. Results of hierarchical multivariate regression analyses showed that maternal life events measured during the first part of pregnancy were negatively associated with the child's attention/concentration index, while controlling for overall IQ, gender, and postnatal stress. No associations were found between prenatal maternal cortisol and the offspring's learning and memory.     

The judgment comes with healing in its wings: A call for rational detachment

The necessity to criticize Pellegrino and Thomasma's ‘A philosophical basis of medical practice’ on all methodological levels of scientific practice is defended; a transcendental critique such as their approach is inconsistent with the possibility of science, a theoretical refutation of their work which is internally inconsistent due to its phenomenological/pragmatic stand, an empirical critique of their readings of historical and sociological findings, and a rejection of the possible application of their approach as its social effects sustain or enhance ideological notions about health, healing and the medical practice. Due to the scope of the work under criticism and the breadth of our critique, we cannot give a detailed account on every issue mentioned here.     

Risky choice with heuristics: reply to Birnbaum (2008), Johnson, Schulte-Mecklenbeck, and Willemsen (2008), and Rieger and Wang (2008)

E. Brandst?tter, G. Gigerenzer, and R. Hertwig (2006) showed that the priority heuristic matches or outperforms modifications of expected utility theory in predicting choice in 4 diverse problem sets. M. H. Birnbaum (2008) argued that sets exist in which the opposite is true. The authors agree--but stress that all choice strategies have regions of good and bad performance. The accuracy of various strategies systematically depends on choice difficulty, which the authors consider a triggering variable underlying strategy selection. Agreeing with E. J. Johnson, M. Schulte-Mecklenbeck, and M. C. Willemsen (2008) that process (not "as-if") models need to be formulated, the authors show how quantitative predictions can be derived and test them. Finally, they demonstrate that many of Birnbaum's and M. O. Rieger and M. Wang's (2008) case studies championing their preferred models involved biased tests in which the priority heuristic predicted data, whereas the parameterized models were fitted to the same data. The authors propose an adaptive toolbox approach of risky choice, according to which people first seek a no-conflict solution before resorting to conflict-resolving strategies such as the priority heuristic.