Restricted mean survival time as a summary measure of time‐to‐event outcome

Many clinical research studies evaluate a time‐to‐event outcome, illustrate survival functions, and conventionally report estimated hazard ratios to express the magnitude of the treatment effect when comparing between groups. However, it may not be straightforward to interpret the hazard ratio clinically and statistically when the proportional hazards assumption is invalid. In some recent papers published in clinical journals, the use of restricted mean survival time (RMST) or τ ‐year mean survival time is discussed as one of the alternative summary measures for the time‐to‐event outcome. The RMST is defined as the expected value of time to event limited to a specific time point corresponding to the area under the survival curve up to the specific time point. This article summarizes the necessary information to conduct statistical analysis using the RMST, including the definition and statistical properties of the RMST, adjusted analysis methods, sample size calculation, information fraction for the RMST difference, and clinical and statistical meaning and interpretation. Additionally, we discuss how to set the specific time point to define the RMST from two main points of view. We also provide developed SAS codes to determine the sample size required to detect an expected RMST difference with appropriate power and reconstruct individual survival data to estimate an RMST reference value from a reported survival curve.     

“I wish someone would explain why I am in care”: The impact of children and young people's lack of understanding of why they are in out‐of‐home care on their well‐being and felt security

Having a good understanding of one's origins and history is known to be significant in identity development. Drawing on a large‐scale online survey of looked after children's subjective well‐being, this paper demonstrates that a significant number of children and young people (age 4–18 years) did not fully understand the reasons for their entry to care. The paper explores the effect of this lack of knowledge on children's well‐being and on their feelings of being settled in their current placement. The study reiterates the need for professionals to be honest and open with children in out‐of‐home care and the need to specifically address, perhaps repeatedly, why a child is not living with their birth family.     

Changing paradigms in measuring national well‐being: How does Korea rank “beyond GDP”?

Academics, politicians, and citizens around the world are calling for multidimensional measures of national well‐being to be included in public policy‐making. Under the motto “The Future of Well‐Being,” the 6th OECD World Forum recently pushed forward this debate in Incheon, Korea. Comparing multidimensional well‐being measures across countries, Korea ranks well in income and health, but shows deficiencies in social support, perceived freedom over life choices, air quality, and work‐life balance. Multidimensional measures of well‐being are increasingly being adopted by policy‐makers around the world to improve people's lives.     

Longitudinal patterns of anger reactivity and risk‐taking: The role of peer‐context

The current study examined the interplay between children's dispositional anger and susceptibility to peers' influence in increasing children's risk‐taking behaviors. Participants in the current study were children from a larger study of temperament and social–emotional development who were followed across 9, 24, 36, 48, and 60 months. Dispositional anger was measured using mothers' reports across 9 and 48 months. At 60 months, children played a risk‐taking computer game in presence of an unfamiliar peer who watched the child play. The child's risk‐taking was assessed during the game as the unfamiliar peers' reactions were coded based on comments that were peer directed, reflective of praising the target child's performance, or object directed, indicative of excitement toward the game. A latent profile analysis revealed three longitudinal anger profiles across infancy to early childhood: high stable, average stable, and low stable anger. Results suggested that as peers' object‐directed comments predicted risk‐taking independent of children's anger, the association between peer‐directed comments and risk‐taking was dependent on children's dispositional anger. Specifically, when peers praised the target child's performance, children in the high stable anger profile showed increased risk‐taking propensity. Findings are discussed based on the importance of considering both temperamental characteristics and aspects of the peer context in relation to children's risk‐taking.     

START: single‐to‐double arm transition design for phase II clinical trials

Phase II clinical trials designed for evaluating a drug's treatment effect can be either single‐arm or double‐arm. A single‐arm design tests the null hypothesis that the response rate of a new drug is lower than a fixed threshold, whereas a double‐arm scheme takes a more objective comparison of the response rate between the new treatment and the standard of care through randomization. Although the randomized design is the gold standard for efficacy assessment, various situations may arise where a single‐arm pilot study prior to a randomized trial is necessary. To combine the single‐ and double‐arm phases and pool the information together for better decision making, we propose a Single‐To‐double ARm Transition design (START) with switching hypotheses tests, where the first stage compares the new drug's response rate with a minimum required level and imposes a continuation criterion, and the second stage utilizes randomization to determine the treatment's superiority. We develop a software package in R to calibrate the frequentist error rates and perform simulation studies to assess the trial characteristics. Finally, a metastatic pancreatic cancer trial is used for illustrating the decision rules under the proposed START design.     

Links between attachment and theory of mind in childhood: Meta‐analytic review

Theoretical models suggest a relation between children's attachment and their theory of mind (ToM), but existing empirical studies are inconclusive with respect to the existence and magnitude of this association. We present the first meta‐analytic review of available studies on the attachment‐ToM association during childhood. Fifteen research on attachment‐ToM links among typically developed children aged 2 to 6 were reviewed and 12 studies that report correlations between attachment and ToM (N = 629) were included in a quantitative meta‐analysis. Meta‐analytic results showed that the higher attachment security, the better ToM skills; the combined effect size for this association was moderate, r = .30. These findings are discussed in‐depth and future research directions are proposed.     

State attachment variability across distressing situations in middle childhood

Contemporary research suggests that attachment has both a trait‐like, stable component, and a state‐like component that varies across contexts. In the current study, we assessed state attachment variability across comparably distressing situations in middle childhood. In two samples, children reported their expectations of maternal support in each situation. Additionally, we administered trait attachment and psychological well‐being measures. Results indicated that, overall, children varied in their expectations across situations: more than half of the variance was explained by intra‐individual differences across situations. Results revealed two components underlying variability: a Signal‐and‐Support component reflecting expectations of support‐seeking and receiving, and a Back‐on‐Track component reflecting expectations of stress reduction and comfort. State attachment variability was related to individual differences in trait attachment: children who are more securely attached at the trait level, overall appear to vary less in their state attachment, likely due to their high mean state attachment scores across situations. When the mean state attachment scores are accounted for, more securely attached children seem to vary more, suggesting that their state attachment expectations are more sensitive to contextual fluctuations. Importantly, degree of state attachment variability explained psychological well‐being over and above trait attachment.     

Let's not get tied into knots: a response to Newman, (2018)—Vygotsky,Wittgenstein and sociocultural theory

The September 2018 issue of this journal included an article by Newman, (2018) that challenges research carried out on second language acquisition (henceforth, SCT‐L2) informed by the psychological theory proposed by L. S. Vygotsky. We would like to respond to Newman's critique, which he problematizes as three “knots” that he then undertakes to untie through analysis of Vygotsky's writings contained in Vygotsky's two most popular works, Thought and Language and Mind in Society. We first summarize Newman's knots and his approach to untying them. We then present our response to each of these in turn.     

Sampling from a Max‐Stable Process Conditional on a Homogeneous Functional with an Application for Downscaling Climate Data

Conditional simulation of max‐stable processes allows for the analysis of spatial extremes taking into account additional information provided by the conditions. Instead of observations at given sites as usually done, we consider a single condition given by a more general functional of the process as may occur in the context of climate models. As the problem turns out to be intractable analytically, we make use of Markov chain Monte Carlo methods to sample from the conditional distribution. Simulation studies indicate fast convergence of the Markov chains involved. In an application to precipitation data, the utility of the procedure as a tool to downscale climate data is demonstrated.