Statistical approaches for conducting network meta-analysis in drug development

We introduce health technology assessment and evidence synthesis briefly, and then concentrate on the statistical approaches used for conducting network meta-analysis (NMA) in the development and approval of new health technologies. NMA is an extension of standard meta-analysis where indirect as well as direct information is combined and can be seen as similar to the analysis of incomplete-block designs. We illustrate it with an example involving three treatments, using fixed-effects and random-effects models, and using frequentist and Bayesian approaches. As most statisticians in the pharmaceutical industry are familiar with SAS? software for analyzing clinical trials, we provide example code for each of the methods we illustrate. One issue that has been overlooked in the literature is the choice of constraints applied to random effects, and we show how this affects the estimates and standard errors and propose a symmetric set of constraints that is equivalent to most current practice. Finally, we discuss the role of statisticians in planning and carrying out NMAs and the strategy for dealing with important issues such as heterogeneity.     

The Dynamics of Disaster Recovery: Resilience and Entropy in Hurricane Response Systems 2005–2008

The challenge for policy makers and disaster managers is to achieve a balance between two dynamics — resilience and entropy — in order to develop sustainable risk reduction. Achieving an appropriate balance between resilience and entropy in any given community requires a systematic exploration of both dynamics. The recent hurricanes that struck Louisiana, Hurricane Katrina on August 29, 2005 and Hurricane Gustav, on September 1, 2008, offer an unusual opportunity to assess the degree to which both dynamics operated following Hurricane Katrina.     

Children's reactions to sibling loss

Loss of a child is a severe trauma to the members of any family. Although the reactions of parents to the loss of a child has received a considerable amount of attention in the literature, relatively little has been written about the impact of such a loss on the remaining sibling(s). The effect of sibling loss on a child is complicated by many factors; among them are the tendency of children to deny the reality of death and the feelings associated with this experience, as well as the manner in which the parents are able to cope with the loss. This article reviews the available literature and calls for more research dealing with the impact of the loss of a child on the entire family system.     

Patterns of Autonomic Arousal in Imaginal Situations of Winning and Losing in Problem Gambling

AIMS: To examine changes in skin conductance level (SCL), for problem gamblers in response to personally relevant imaginal tasks, representing winning or losing. SETTING, DESIGN, PARTICIPANTS AND MEASUREMENTS: SCL and subjective arousal were compared for problem poker machine gamblers (n = 13) and a control group (n = 20). Participants were asked to describe a situation in which they had (a) won and (b) lost during a period of gambling. Before and during the task, recordings of SCL were taken. FINDINGS: There were significant differences between responses of problem and social gamblers. A significant interaction indicated that social gamblers became more aroused in reaction to winning than losing, whereas problem gamblers became equally aroused in response to both tasks. CONCLUSIONS: The results suggest that it may be responses to losing, rather than winning that are paramount to the development and maintenance of problem gambling.     

Machine gaming in Sydney clubs: characteristics of the supporting resident populations

This research provided background for surveys and interviews in later stages of a 3 part project. It aimed to identify, from secondary research, sociodemographic characteristics which tend to support registered clubs and their machine gaming activities in the Sydney Statistical Division. Using multiple methods including Pearson's Product Moment correlation, Principal Components factor analysis, and stepwise regression, the study profiled Sydney populations which spend highly on gaming machines. The most important sociodemographic predictors of Sydney statistical local areas where per capita gaming machine expenditure is high are large proportions of the adult resident population who were born in Malta, Greece, Lebanon, China, Italy, Vietnam, Yugoslavia, India or the Philippines; have no vocational or tertiary qualifications; or are unemployed.     

Many a slip between cup and lip. Process evaluation of a program to promote and support evidence-based public health practice

The main aims of this study are to document whether an intervention for promoting evidence-based public health practice had been delivered as intended and to explore the reasons for its lack of impact. Process data from the implementation of the program and data from interviews with 40 public health physicians are analyzed. Although they expressed satisfaction with the service, the doctors experienced the program as rather irrelevant for their daily work. They did not perceive that they dealt with many issues relevant for the use of research information, and if they did, referring to research would not make any difference to the way others perceived their advice. There is a need to develop more overlying strategies for integrating evidence into decision making than addressing the individual level.     

Determinants of microbat communities in urban forest remnants: a rapid landscape scale assessment

Urban Ecosystems - Urbanisation affects fauna in many ways; with some species persisting and going on to dominate urban habitats, while other species decline over time due to habitat disturbance...     

Employee absence,age and tenure: A study of nonlinear effects and trivariate models

Multiple regression techniques were used to explore the nature of the relationships between age, tenure and absence in 2417 British local government workers drawn from three work groups. The data were collected from organizational records and included measures of both non-certified absence and medically certified absence. Linear and curvilinear associations among age, tenure and absence were examined. The possible moderating or mediating role of tenure in the relationship between age and absence was subsequently analysed. The data revealed linear relationships between age and absence that were negative for non-certified absence and positive for certified absence. In contrast, curvilinear relationships were found between tenure and absence that were U-shaped for noncertified absence and inverse U-shaped for certified absence. Tenure was found to moderate but not to mediate the relationship between age and absence. The implications of the results are discussed in the context of the changing age and career paths of the workforce, and of methodological issues in absence research.