Efficacy and toxicity monitoring via Bayesian predictive probabilities in phase II clinical trials

Bayesian monitoring strategies based on predictive probabilities are widely used in phase II clinical trials that involve a single efficacy binary variable. The essential idea is to control the predictive probability that the trial will show a conclusive result at the scheduled end of the study, given the information at the interim stage and the prior beliefs. In this paper, we present an extension of this approach to incorporate toxicity considerations in single-arm phase II trials. We consider two binary endpoints representing response and toxicity of the experimental treatment and define the result as successful at the conclusion of the study if the posterior probability of an high efficacy and that of a small toxicity are both sufficiently large. At any interim look, the Multinomial-Dirichlet distribution provides the predictive probability of each possible combination of future efficacy and toxicity outcomes. It is exploited to obtain the predictive probability that the trial will yield a positive outcome, if it continues to the planned end. Different possible interim situations are considered to investigate the behaviour of the proposed predictive rules and the differences with the monitoring strategies based on posterior probabilities are highlighted. Simulation studies are also performed to evaluate the frequentist operating characteristics of the proposed design and to calibrate the design parameters.

     

Determining factors leading affiliates to transfer from an individual accounts pension scheme to a pay-as-you-go pension scheme: Evidence from Argentina

Prior to the recent implementation of the Argentine Integrated Social Security System (SIPA — Sistema Integrado Previsional Argentino ), the 2007 reform represented the first major change in Argentina's old-age social security system since 1994. For the first time, workers contributing to the private defined-contribution individual accounts scheme were able to choose freely to move over to the public pay-as-you-go (PAYG) scheme. This study is an attempt to analyse the special characteristics of those who opted for transfer to the public PAYG scheme and to discover whether the behaviour of these individuals is in line with that of a "simulated worker" attempting to optimize income. The analysis includes an estimate of the probability that individuals with certain characteristics will transfer.     

The Role of Metacognition in Pathological Gambling: A Mediation Model

Pathological gambling involves multitudinous costs related to financial, legal, and public health care aspects, as well as to specific psychological disorders. Despite the overall evidence suggesting that comorbid disorders represent a risk factor for pathological gambling, there is scant evidence on the appropriate treatments for gamblers with such disorders. In this context, metacognitive therapy is an interesting approach because it considers psychological disorders as a result of the activation of perseverative cognitive processes and attentional strategies in response to inner events. Several studies report that metacognition is associated with different psychological problems. This study investigated the relationship among comorbid disorders, metacognition, and pathological gambling. 69 pathological gamblers at the first hospital admission and 58 controls drawn from general population (matched for age, gender, education) completed a battery of self report instruments: Symptom Checklist-90-R, Metacognition Questionnaire 30, South Oaks Gambling Scale. Compared to controls, pathological gamblers showed higher level of comorbid symptomatology and metacognition. Correlation analyses showed that: comorbid symptomatology and metacognition were positively and significantly correlated with pathological gambling; metacognition was positively and significantly associated with comorbid symptomatology. Mediation analysis indicated that dysfunctional metacognitive strategies could have an indirect effect on pathological gambling mediated by concurrent psychological disorders. These findings provide some implications for gambling treatment programs: pathological gamblers should be screened for psychiatric disorders, and metacognitive therapy could be considered a correct treatment of pathological gamblers. Metacognitive therapy might lead to the reduction of the pathological gambling by the diminishing of the concurrent psychological disorders.     

Close Social Networks Among Older Adults: The Online and Offline Perspectives

Population Research and Policy Review - Qualitative studies have found that the use of Information and Communication Technologies is related to an enhanced quality of life for older adults, as...     

Inclusiveness as Construction of Open Identity: How Social Relationships Affect Attitudes Towards Immigrants in European Societies

Studies of individual and group-level sources of prejudice have contributed to today’s greater understanding of the emergence of prejudice and discriminatory attitudes towards immigrants. Yet, scholars have claimed that future research should investigate institutional and socio-political macro-level factors affecting individuals’ attitudes towards outsiders (Ceobanu and Escandell in Ann Rev Sociol 36:309–328, 2010). To contribute to filling this knowledge gap, this article goes across levels of analysis and theories to provide insights about group-level sources influencing attitudes towards immigrants. These sources are taken into account as both institutional and social factors involved in processes of national identity constructions. To this purpose, this work combines Blumer’s perspective (Pac Sociol Rev 1:3–7, 1958) with both the distinction Weber (Wirtschaft und Gesellschaft. Tübingen, Mohr, 1922) made between open and closed social relationships and some other theoretical contributions that emerged in the field. The findings of a multilevel analysis confirm that, whereby inclusive socio-political factors are involved in the processes of countries’ identity constructions, individuals show more positive attitudes towards immigrants. In addition, in inclusive countries, a society’s high regard for its own traditions and customs influences individual members to appreciate other cultures and show positive dispositions towards outsiders.     

Mind the Covid-19 crisis: An evidence-based implementation of Next Generation EU

This paper develops an evidence-based approach to the selection and prioritisation of Next Generation EU (NGEU) projects for timely implementation and impact of the Recovery Plan for Europe. The analysis of a large sample of projects, currently funded by the European Union (EU) with the same priorities and objectives of NGEU, suggests that a timely implementation should be driven – within the EU Commission coordination framework – by national governments liaising directly with their citizens through participatory procedures, involving relevant stakeholders. Simplified implementation procedures with clear spatial targeting and limited involvement of regional authorities are necessary conditions for the avoidance of implementation delays.     

COVID‐19 as a breakdown in the texture of social practices

‘A lot of things need to be repaired and a lot of relationships are in need of a knowledgeable mending. Can we start to talk/write about them?’ This invitation — sent by one of the authors to the others — led us, as feminist women in academia, to join together in an experimental writing about the effects of COVID‐19 on daily social practices and on potential (and innovative) ways for repairing work in different fields of social organization. By diffractively intertwining our embodied experiences of becoming together‐with Others, we foreground a multiplicity of repair (care) practices COVID‐19 is making visible. Echoing one another, we take a stand and say that we need to prevent the future from becoming the past. We are not going back to the past; our society has already changed and there is a need to cope with innovation and repairing practices that do not reproduce the past.     

The Effect on Fertility of the 2003–2011 War in Iraq

This article provides the first detailed account of recent fertility trends in Iraq, with a particular focus on the changes resulting from the 2003–2011 war and the factors underlying them. The study is based on retrospective birth history data from the 2006 and 2011 Iraq Multiple Indicator Cluster Surveys (I‐MICS). Estimates from the two surveys indicate that total fertility remained stable from 1997 to 2010, at about 4.5 children per woman. However, examination of the age patterns of fertility reveals an abrupt shift in the timing of births, with adolescent fertility rising by over 30 percent soon after the onset of the war. A decomposition analysis shows that the rise in early childbearing is due to an increased prevalence of early marriage among less‐educated women. The prevalence of early marriage and childbearing among women with secondary or higher education is relatively low and has not increased after 2003.     

Optimal predictive sample size for case–control studies

Summary.  The identification of factors that increase the chances of a certain disease is one of the classical and central issues in epidemiology. In this context, a typical measure of the association between a disease and risk factor is the odds ratio. We deal with design problems that arise for Bayesian inference on the odds ratio in the analysis of case–control studies. We consider sample size determination and allocation criteria for both interval estimation and hypothesis testing. These criteria are then employed to determine the sample size and proportions of units to be assigned to cases and controls for planning a study on the association between the incidence of a non-Hodgkin's lymphoma and exposition to pesticides by eliciting prior information from a previous study.