A novel case‐control subsampling approach for rapid model exploration of large clustered binary data

In many settings, an analysis goal is the identification of a factor, or set of factors associated with an event or outcome. Often, these associations are then used for inference and prediction. Unfortunately, in the big data era, the model building and exploration phases of analysis can be time‐consuming, especially if constrained by computing power (ie, a typical corporate workstation). To speed up this model development, we propose a novel subsampling scheme to enable rapid model exploration of clustered binary data using flexible yet complex model set‐ups (GLMMs with additive smoothing splines). By reframing the binary response prospective cohort study into a case‐control–type design, and using our knowledge of sampling fractions, we show one can approximate the model estimates as would be calculated from a full cohort analysis. This idea is extended to derive cluster‐specific sampling fractions and thereby incorporate cluster variation into an analysis. Importantly, we demonstrate that previously computationally prohibitive analyses can be conducted in a timely manner on a typical workstation. The approach is applied to analysing risk factors associated with adverse reactions relating to blood donation.     

A Community and Medical Library Collaboration to Address Senior Caregivers Barriers to Health Services Access

This describes an outreach program to improve access to community resources and online health information for the lay public and professionals engaged in caregiving to seniors. An academic health sciences library and a coalition of community organizations collaborated to develop an authoritative, web-enabled clearinghouse that consolidated access to regional and national health and social service resources and online health information. Findings from a mixed-methods approach of roundtable discussions, key informant structured interviews, and surveys of professionals involved in senior care planning and discharge management were used to develop, pilot test, and evaluate the project. The website was promoted through a series of webinars outlining the range of services and resources available as well as engagement with a variety of community health care organizations. This project advanced understanding of the needs of seniors and their caregivers and created mechanisms to improve access to authoritative health care information supporting senior care. Community feedback on the website launch highlights its value for the lay public and professional caregivers. It also provided a platform for volunteerism and service learning through which individuals can have a collective impact on their community.     

健康体检信息管理系统的应用

健康体检信息管理系统是医院医疗信息化的重要组成部分,本文针对建设现状,阐述建设该系统设计的主要原则、方法、建设方案。     

医院绩效管理系统的设计与实践

本文报告了北京军区医院绩效管理的探索设计与实践。提出医院绩效管理的五个基本要素;构建了两级绩效管理平台和四级五层考评体系。绩效管理使全区医院进入了科学发展的快车道,大幅度提升了医院综合实力,提高了医疗保障能力。     

Globally optimal trial design for local decision making

Value of information methods allows decision makers to identify efficient trial design following a principle of maximizing the expected value to decision makers of information from potential trial designs relative to their expected cost. However, in health technology assessment (HTA) the restrictive assumption has been made that, prospectively, there is only expected value of sample information from research commissioned within jurisdiction. This paper extends the framework for optimal trial design and decision making within jurisdiction to allow for optimal trial design across jurisdictions. This is illustrated in identifying an optimal trial design for decision making across the US, the UK and Australia for early versus late external cephalic version for pregnant women presenting in the breech position. The expected net gain from locally optimal trial designs of US$0.72M is shown to increase to US$1.14M with a globally optimal trial design. In general, the proposed method of globally optimal trial design improves on optimal trial design within jurisdictions by: (i) reflecting the global value of non-rival information; (ii) allowing optimal allocation of trial sample across jurisdictions; (iii) avoiding market failure associated with free-rider effects, sub-optimal spreading of fixed costs and heterogeneity of trial information with multiple trials.     

国境口岸食源性微生物检测基因芯片探针设计新方法的研究

SNP位点选择是国境口岸食源性微生物基因芯片检测探针设计的关键环节,目前主要依靠手工完成,严重影响着检测速度和检测质量,为此提出了一种基于遗传算法的SNP位点的自动选择方法。该方法运用粗糙集理论评估SNP位点组合的分类能力,综合与检测实验密切相关的设计指标,采用遗传算法进行优化搜索。实验结果表明,该方法具有很好的稳健性和较快的收敛速度,能够准确地寻找食源性微生物的SNP位点组合,为大规模的检测芯片探针自动设计提供了快速可靠的途径,缩短了国境口岸致病微生物的检测时限,提高了检测结果的准确性。     

Designs for dose–escalation trials with quantitative responses

In a dose–escalation trial for a new drug, each successive dose is tested on a new cohort of volunteer subjects, so that if any dose produces severe adverse reactions then higher doses are not tested. However, if there are other differences between the cohorts, such as differences in environmental health factors, type of person or experimental procedure, then these differences may obscure the differences between doses. Therefore, cohorts should be fitted in the analysis, as either fixed or random effects. I suggest that, if this is done, then there are three simple principles that reduce variance (i) allocating no more than half the subjects in any cohort to any single dose; (ii) subject to safety constraints, using as many different doses as possible in each cohort; (iii) using one more cohort than the number of doses, without increasing the total number of subjects. Using these principles, I propose some new designs that conform to the safety rules of traditional dose–escalation trials while reducing the variance of the estimators of differences between the doses by a factor of two or more, for the same number of subjects. Copyright © 2009 John Wiley & Sons, Ltd.     

Childhood Asthma and Environmental Exposures at Swimming Pools: State of the Science and Research Recommendations

Objectives

Recent studies have explored the potential for swimming pool disinfection by-products (DBPs), which are respiratory irritants, to cause asthma in young children. Here we describe the state of the science on methods for understanding children’s exposure to DBPs and biologics at swimming pools and associations with new-onset childhood asthma and recommend a research agenda to improve our understanding of this issue.

Data sources

A workshop was held in Leuven, Belgium, 21–23 August 2007, to evaluate the literature and to develop a research agenda to better understand children’s exposures in the swimming pool environment and their potential associations with new-onset asthma. Participants, including clinicians, epidemiologists, exposure scientists, pool operations experts, and chemists, reviewed the literature, prepared background summaries, and held extensive discussions on the relevant published studies, knowledge of asthma characterization and exposures at swimming pools, and epidemiologic study designs.

Synthesis

Childhood swimming and new-onset childhood asthma have clear implications for public health. If attendance at indoor pools increases risk of childhood asthma, then concerns are warranted and action is necessary. If there is no such relationship, these concerns could unnecessarily deter children from indoor swimming and/or compromise water disinfection.

Conclusions

Current evidence of an association between childhood swimming and new-onset asthma is suggestive but not conclusive. Important data gaps need to be filled, particularly in exposure assessment and characterization of asthma in the very young. Participants recommended that additional evaluations using a multidisciplinary approach are needed to determine whether a clear association exists.     

前馈控制方法及其在丹红注射液醇沉工艺品质提升中的应用

该文基于质量源于设计理念,建立一种中药生产过程前馈控制方法,以减少原料质量波动对产品质量的影响.以丹红注射液的醇沉工艺为例,通过Box-Behnken试验设计,建立浓缩液性质、工艺参数与醇沉上清液性质之间的数学模型,并建立工艺参数优化模型,根据物料性质计算合适的工艺参数.比较了使用优化前后工艺参数进行醇沉得到的上清液质量.结果表明,使用前馈控制方法优化醇沉工艺参数能有效地控制上清液质量,有助于提高醇沉工艺上清液质量的一致性.     

中药儿童群体药动学试验设计要点

儿童由于身体发育尚未完善,药物在体内分布代谢有其自身的特点,且在不同年龄、体质量区间的差别很大,使得儿童用药剂量不能简单地参考成人用药剂量进行折算。群体药动学是研究目标人群药物代谢参数的有效方法,尤其适用于儿童这一特殊群体,可有效避免经典药物代谢取血点多所带来的伤害,并可充分了解协变量影响因素的大小,可见掌握药物在儿童中的群体典型值意义重大。提出了中药在儿童群体中开展药动学研究的试验要点与技术方法。