Early stopping by using stochastic curtailment in a three-arm sequential trial

Summary. Interim analysis is important in a large clinical trial for ethical and cost considerations. Sometimes, an interim analysis needs to be performed at an earlier than planned time point. In that case, methods using stochastic curtailment are useful in examining the data for early stopping while controlling the inflation of type I and type II errors. We consider a three-arm randomized study of treatments to reduce perioperative blood loss following major surgery. Owing to slow accrual, an unplanned interim analysis was required by the study team to determine whether the study should be continued. We distinguish two different cases: when all treatments are under direct comparison and when one of the treatments is a control. We used simulations to study the operating characteristics of five different stochastic curtailment methods. We also considered the influence of timing of the interim analyses on the type I error and power of the test. We found that the type I error and power between the different methods can be quite different. The analysis for the perioperative blood loss trial was carried out at approximately a quarter of the planned sample size. We found that there is little evidence that the active treatments are better than a placebo and recommended closure of the trial.     

Rehabilitation Programs for Elderly Women Inpatients with Schizophrenia

ABSTRACT

This study aims to describe rehabilitation and resocialization methods we believe to be appropriate for application to female patients with schizophrenia, in a psychiatric unit with a predominantly older population. We briefly describe the unit and the interventions used as an example of the proposed rehabilitation and resocialization methods applied. The article provides an overview to guide accurate intervention, particularly in inpatient women, in different types of cognitive impairment under the broad category of schizophrenia. Our clinical approach includes a token economy approach, cognitive remediation therapy, and social skills training. The token economy intervention is particularly directed to patients that present with a high mental deterioration and/or debility. Cognitive remediation training is applicable to subjects with both cognitive and social dysfunction, but that do not possess signs of an organic cerebral illness or of substance abuse. Social skills training can be the third step to resocialization, training verbal and nonverbal communication competencies.     

Causes,effects and mitigation of unreliable healthcare supplies

This study investigates the means by which hospitals can improve the reliability of their medical supply value streams. Field research involving pharmacy supplies in eight Australasian public sector hospitals utilised a rigorous, multi-method data collection procedure based around the uncertainty circle model. Value stream maturity, performance inhibitors and pathways to effective improvement are explored. The high levels of value stream uncertainty detected are commonly the result of process immaturity and poor inter-functional integration. Chief among the common root causes is failure by the executive to acknowledge the strategic value of medical supplies management, which ultimately leads to higher materials cost and increased risk of a medical mishap. The study demonstrates how managers can use systems thinking and a context-free performance benchmark to identify effective interventions and potentially transferable best practices.     

Hierarchical Bayesian models to assess between- and within-batch variability of pathogen contamination in food

Assessing within-batch and between-batch variability is of major interest for risk assessors and risk managers in the context of microbiological contamination of food. For example, the ratio between the within-batch variability and the between-batch variability has a large impact on the results of a sampling plan. Here, we designed hierarchical Bayesian models to represent such variability. Compatible priors were built mathematically to obtain sound model comparisons. A numeric criterion is proposed to assess the contamination structure comparing the ability of the models to replicate grouped data at the batch level using a posterior predictive loss approach. Models were applied to two case studies: contamination by Listeria monocytogenes of pork breast used to produce diced bacon and contamination by the same microorganism on cold smoked salmon at the end of the process. In the first case study, a contamination structure clearly exists and is located at the batch level, that is, between batches variability is relatively strong, whereas in the second a structure also exists but is less marked.     

Macroergonomic aspects in the design of development programs in IDCs

This paper revisits three reports on ergonomic aspects of development initiatives taking place in Industrially Developing Countries (IDCs). These include a macro-ergonomics intervention in a habitation community in Cape Verde (aimed at designing solutions contributing to sustainable development), the evolution of poultry growers' control strategies as an integrative broiler operation is introduced in Mozambique, and a set of macro-ergonomic considerations related to the Agro Forestry Village Project in Mozambique. The paper seeks to set the reviewed development endeavors against the backdrop of the goals of ergonomics interventions. This reflection may inform development agents in future processes of design and implementation of integrated community and work systems transformation.     

The footwear factory's assembly sector: opposing organizational structure and quality from the ergonomic work analysis

Data from 2006 indicated that Brazilian footwear leather industry was composed of approximately 9,488 formally registered establishments, considering the leather industry, footwear and leather goods. It was responsible for 211,582 people employed. However, in spite of having many employees, this kind of organization found several problems when analyzed from the ergonomics view. With this premise, then, in order to identify bottlenecks and other engineering problems that could cause discomfort and motivation lack among workers, leading directly to the loss of the product quality, the assembly sector of women's shoes factory was characterized.     

Life skills training and the politics of personal effectiveness

In recent years social and life skills curriculum has emerged to occupy an important place in new training initiatives, particularly those associated with YTS and pre-vocational courses such as TVEI, CPVE and City and Guids 365.* one level the attraction of‘life skills’training is that it is relevant and address, in ways that traditional Liberal and General Studies could not, the practical problems likely to affect young people as adults, as parents and as employees. another, ambiguity surrounds the criteria upon which such skills for living are constructed and appraised, not least because of their close behavioural connection with altering young peoples’attitudes toward authority, industry and society. Despite recent concern about the dangers of bias and indoctrination elsewhere in mainstream education, this controversial aspect of government intervention in vocational training (DEP 1981; MSC 1981; DEP 1984) has escaped the critical attention of those who currently express concern about standards in education (Scrution et al 1985). For this reason the paper seeks to examine the kind of‘official’thinking which lies behind life skills training, and the skills which are thought necessary to enhance the‘personal effectiveness’of young people. This would seem all the more important in view of the government's contention that technical and vocational education (14-18) now constitutes a viable alternative for those who fail to succeed in mainstream education. (DEP 1981, 1984; MSC 1981, 1982a).