Comparison of dichotomized and distributional approaches in rare event clinical trial design: a fixed Bayesian design

This research was motivated by our goal to design an efficient clinical trial to compare two doses of docosahexaenoic acid supplementation for reducing the rate of earliest preterm births (ePTB) and/or preterm births (PTB). Dichotomizing continuous gestational age (GA) data using a classic binomial distribution will result in a loss of information and reduced power. A distributional approach is an improved strategy to retain statistical power from the continuous distribution. However, appropriate distributions that fit the data properly, particularly in the tails, must be chosen, especially when the data are skewed. A recent study proposed a skew-normal method. We propose a three-component normal mixture model and introduce separate treatment effects at different components of GA. We evaluate operating characteristics of mixture model, beta-binomial model, and skew-normal model through simulation. We also apply these three methods to data from two completed clinical trials from the USA and Australia. Finite mixture models are shown to have favorable properties in PTB analysis but minimal benefit for ePTB analysis. Normal models on log-transformed data have the largest bias. Therefore we recommend finite mixture model for PTB study. Either finite mixture model or beta-binomial model is acceptable for ePTB study.     

Is ethnic prejudice declining in Britain? Change in social distance attitudes among ethnic majority and minority Britons

Most literature on racial prejudice deals with the racial attitudes of the ethnic majority and ethnic minorities separately. This paper breaks this tradition. We examine the social distance attitudes of white and non‐white British residents to test if these attitudes follow the same trends over time, whether they are driven by the same social processes and whether they are inter‐related. We have three main findings. Firstly, social distance from other ethnic groups has declined over time for both white and ethnic minority Britons. For the white majority there are both period and cohort elements to this decline. Secondly, we see some evidence that social distance between the majority and minority groups is reciprocal. Specifically, minorities who experience rejection by the white British feel a greater sense of distance from them. Thirdly, we find that all groups share the perception of the same ethnic hierarchy. We see evidence of particularly widespread hostility towards Muslim Britons from all ethnic groups suggesting that Muslims are singled out for negative attention from many British residents of all other backgrounds, including a large number who do not express hostility to other groups.     

Immigrant Bilingualism in Spain: An Asset or a Liability?

This study contributes to the ongoing debate about bilingual advantage and examines whether bilingual immigrant youths fare better, as well as, or worse academically than the matching group of monolinguals. Using data from Spain, where close to half of immigrants speak Spanish as their native language, we found no evidence of costs of bilingualism: bilingual youths did benefit from their linguistic skills. Their advantage, however, manifested itself not uniformly across discrete outcomes, but in a direct trajectory toward higher educational attainment. Bilingualism neutralized the possible negative effect of ethnic origins and extended the positive effect of high parental ambition. Implications for theory and practice are discussed.     

Ice pack induced perineal analgesia after spontaneous vaginal birth: Randomized controlled trial

Background

Ice-pack is widely used for alleviating postpartum perineal pain sustained after birth related perineal trauma. However, it lacks robust evidence on timing and frequency of applications, to ensure the effective and safe use of this therapy.

Social Capital and Self Perceived Health Among European Older Adults

There is increasing interest among researchers in the effects of social capital on the health of older adults. One of the key policy question for an ageing population concerns how do we identify the factors that influence health. Very recently, an increasing interest on social capital as a key determinant for health has developed and, surprisingly, not much is known for the European population. This paper analyzes the association between social capital and self-perceived health among older adults in Europe using a mixed effects logistic model. Social capital is considered in its two components—bonding and bridging—in order to understand if the relations inside or outside an individual inner circle have a different association with health. Our results give empirical support to the role of individual social capital in preventing a poor self-perceived health. This means that social capital, especially the bridging component of it, can be one of the key factors of ageing in good health and should be fostered by policy makers in order to give an answer to one of the most compelling challenge of our century: population ageing.     

Does Tourism Consumption Behaviour Mirror Differences in Living Standards?

Based on the theoretical foundation of well-being measurement, the study explores differences in living standards by analysing the distribution of tourism expenditure. A mixture of regression models is used to explore the heterogeneity in tourism consumption by identifying groups of families with similar tourism consumption behaviour as a function of certain socio-demographic and economic factors. The empirical analysis, performed on Italian expenditure data, suggests that there are three different patterns of consumption behaviour conditional to the socio-demographic and economic covariates in the tourism market and that differences in tourism consumption between groups of households mirror inequalities in living standards.     

Reciprocal relationships between psychosocial work characteristics and sleep problems: A two-wave study

Sleep problems are common and impair the health and productivity of employees. Work characteristics constitute one possible cause of sleep problems, and sleeping poorly might influence wellbeing and performance at work. This study examines the reciprocal associations between sleep problems and psychosocial work characteristics. The participants were 1744 full-time employed individuals (56% women; mean age 38 years in 2007) from the Young Finns study who responded to questionnaires on work characteristics (conceptualised by the demand–control model and effort–reward imbalance model) and sleep problems (Jenkins Sleep Scale) in 2007 and 2012. Cross-lagged structural equation models are used to examine the associations. The results show that low control and low rewards at baseline predicted sleep problems. Baseline sleep problems predicted higher effort, higher effort–reward imbalance, and lower reward. Sleep problems also predicted lower odds for belonging to the low (rather than high) job strain group and active jobs group. The association between work characteristics and sleep problems appears to be reciprocal, with a stressful work environment increasing sleep problems, and sleep problems influencing future work characteristics. The results emphasise the importance of interventions aimed at both enhancing sleep quality and reducing psychosocial risks at work.     

The Effects of Pop-up Harm Minimisation Messages on Electronic Gaming Machine Gambling Behaviour in New Zealand

In New Zealand a simple pop-up message feature that provides gambling session information and forces a break in play is mandatory on all electronic gaming machines in all venues (EGMs). Previous research has demonstrated small effects of more sophisticated pop-up messages tested predominantly in laboratory environments. The present research examined gambler engagement with and views on the New Zealand pop-up messages and on the relationship between pop-up messages and EGM expenditure. A sample of gamblers was recruited at casino and non-casino (pub) EGM venues. Most participants were aware of pop-up messages (57 %) and many saw them often (38 %). Among gamblers who reported seeing pop-up messages, half read the message content, and a quarter believed that pop-up messages helped them control the amount of money they spend on gambling. Participants who reported being likely to stop gambling in response to pop-up messages spent significantly less money on gambling when variables that were independently associated with EGM expenditure were controlled for. A modest harm minimisation effect of the pop-up message feature that has been operating in New Zealand for 5 years was evident. Suggestions for improvement of the harm minimisation potential of the current pop-up message feature are discussed.