A mathematical model for the simulation of the contraction of burns

A continuum hypothesis-based model is developed for the simulation of the contraction of burns in order to gain new insights into which elements of the healing response might have a substantial influence on this process. Tissue is modeled as a neo-Hookean solid. Furthermore, (myo)fibroblasts, collagen molecules, and a generic signaling molecule are selected as model components. An overview of the custom-made numerical algorithm is presented. Subsequently, good agreement is demonstrated with respect to variability in the evolution of the surface area of burns over time between the outcomes of computer simulations and measurements obtained in an experimental study. In the model this variability is caused by varying the values for some of its parameters simultaneously. A factorial design combined with a regression analysis are used to quantify the individual contributions of these parameter value variations to the dispersion in the surface area of healing burns. The analysis shows that almost all variability in the surface area can be explained by variability in the value for the myofibroblast apoptosis rate and, to a lesser extent, the value for the collagen molecule secretion rate. This suggests that most of the variability in the evolution of the surface area of burns over time in the experimental study might be attributed to variability in these two rates. Finally, a probabili

Extrapolation of experimental results through analogical reasoning from latent classes

In the human sciences, experimental research is used to establish causal relationships. However, the extrapolation of these results to the target population can be problematic. To facilitate extrapolation, we propose to use the statistical technique Latent Class Regression Analysis in combination with the analogical reasoning theory for extrapolation. This statistical technique can identify latent classes that differ in the effect of X on Y. In order to extrapolate by means of analogical reasoning, one can characterize the latent classes by a combination of features and then compare these features to features of the target

Assessment policies and academic performance within a single course: The role of motivation and self-regulation.

Despite the frequently reported association of characteristics of assessment policies with academic performance, the mechanisms through which these policies affect performance are largely unknown. Therefore, the current research investigated performance, motivation and self-regulation for two groups of students following the same statistics course, but under two assessment policies: education and child studies (ECS) students studied under an assessment policy with relatively higher stakes, a higher performance standard and a lower resit standard, compared with Psychology students. Results show similar initial performance, but more use of resits and higher final performance (post-resit) under the ECS policy compared with the psychology policy. In terms of motivation and self-regulation, under the ECS policy significantly higher minimum grade goals, performance self-efficacy, task value, time and study environment management, and test anxiety were observed, but there were no significant differences in aimed grade goals, academic self-efficacy and effort regulation. The relations of motivational and selfregulatory factors with academic performance were similar between both assessment policies. Thus, educators should be keenly aware of how characteristics of assessment policies are related to students’ motivation, self-regulation and academic performance

A Randomised Controlled Trial of the I-Deal Life Skills Intervention with Syrian Refugee Adolescents in Northern Lebanon

Armed conflict and displacement pose threats to children’s mental health and psychosocial wellbeing. We report on the findings of an evaluation of I-Deal, a life skills intervention aimed at fostering resilience among early adolescent refugees. We used a parallel group randomised controlled trial to compare I-Deal to a structured recreational activity group (SRA). 325 adolescents in Akkar, Lebanon, 74% of them Syrian, were randomised to I-Deal or SRA. The primary outcome was psychosocial wellbeing; secondary outcomes included psychological distress, prosocial behaviour, hope, self-esteem and social connectedness. Assessments were conducted at baseline, endline and 3-month follow-up. Due to low reliabilities, only wellbeing, distress and hope were included in the analyses. These outcomes showed similar results: no statistically significant changes over time, no significant differences between groups and no significant interaction between group and time. Our findings do not support the effectiveness of I-Deal. Several factors are considered that may help explain the lack of effect, including the aspects of the intervention design, possible measurement error suggested by low reliabilities on several instruments and a ceiling effect on our primary outcome. A replication using rigorously piloted instruments, the selection of outcomes more specifically tailored to the intervention and a nonactive control condition could help provide definitive evidence regarding the effectiveness of the I-Deal intervention. Key implications for practice: - This study contributes to the growing literature on the effectiveness of life skills interventions for refugee adolescents. - The lack of any intervention effects in this study raises important questions about the appropriate focus and role of preventive and promotive interventions with refugee adolescents. - Methodological issues in the study underscore the vital importance of using validated and well piloted measures of appropriately selected intervention outcomes

Supporting Syrian families displaced by armed conflict: A pilot randomized controlled trial of the Caregiver Support Intervention

Background The impact of armed conflict and displacement on children’s mental health is strongly mediated by compromised parenting stemming from persistently high caregiver stress. Parenting interventions for refugees emphasize the acquisition of parenting knowledge and skills, while overlooking the deleterious effects of chronic stress on parenting. War Child Holland’s Caregiver Support Intervention (CSI) aims to strengthen parenting by lowering stress and improving psychosocial wellbeing among refugee parents, while also increasing knowledge and skill related to positive parenting. The CSI is a nine-session group intervention delivered by non-specialist providers. Objective We describe the findings of a two-arm pilot randomized controlled trial of the CSI with Syrian refugees in Lebanon. The primary aim was to test the feasibility of our study methodology prior to conducting a definitive RCT. Methods We recruited 78 families (151 parents), who were randomized to the CSI or a waitlist control group. Data were collected at baseline and post-intervention. Results Randomization was successful, retention was high (99 %), as was intervention completion (95 % among women, 86 % among men). Implementation fidelity was excellent. Blinding was largely, though not completely effective. The CSI group showed significantly increased parental warmth and responsiveness, decreased harsh parenting, lowered stress and distress, improved psychosocial wellbeing, and improved stress management. CSI parents reported increased child psychosocial wellbeing. Control families showed no significant change on any variable. Conclusions Findings demonstrate the feasibility of our methodology for a definitive RCT, and suggest that the CSI shows promise as a scalable approach to strengthening parenting in refugee communities