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Adequate Power (adequate + power)
Selected AbstractsNational AIDS Commissions in Africa: Performance and Emerging ChallengesDEVELOPMENT POLICY REVIEW, Issue 2 2009Erasmus Morah This article consolidates and expands on evidence on how National AIDS Commissions (NACs) in sub-Saharan Africa are measuring up to expectations that drove their rapid adoption across the continent. While their overall performance seems reasonably good, most NACs still lack adequate power and incentive structures to hold line ministries accountable, a key requirement for co-ordinating activities and mainstreaming HIV-AIDS across the public sector. Second-generation African NACs urgently need the authority and institutional stature to effectively co-ordinate the channelling of the larger funds now available through government bureaucracy. The evolution of the epidemic also imposes requirements different from those when the current NAC architecture was crafted. [source] A simulation tool for designing nutrient monitoring programmes for eutrophication assessments,ENVIRONMETRICS, Issue 1 2010Janet Heffernan Abstract This paper describes a simulation tool to aid the design of nutrient monitoring programmes in coastal waters. The tool is developed by using time series of water quality data from a Smart Buoy, an in situ monitoring device. The tool models the seasonality and temporal dependence in the data and then filters out these features to leave a white noise series. New data sets are then simulated by sampling from the white noise series and re-introducing the modelled seasonality and temporal dependence. Simulating many independent realisations allows us to study the performance of different monitoring designs and assessment methods. We illustrate the approach using total oxidised nitrogen (TOxN) and chlorophyll data from Liverpool Bay, U.K. We consider assessments of whether the underlying mean concentrations of these water quality variables are sufficiently low; i.e. below specified assessment concentrations. We show that for TOxN, even when mean concentrations are at background, daily data from a Smart Buoy or multi-annual sampling from a research vessel would be needed to obtain adequate power. Copyright © 2009 Crown Copyright [source] Have the courts and the motor vehicle departments adequate power to control the hard-core drunk driver?ADDICTION, Issue 12 2001Robert B. Voas First page of article [source] Power of the Rank Adjacency Statistic to Detect Spatial Clustering in a Small Number of RegionsGEOGRAPHICAL ANALYSIS, Issue 1 2001John Paul Ekwaru The rank adjacency statistic D is a statistical method for assessing spatial autocorrelation or clustering of geographical data. It was originally proposed for summarizing the geographical patterns of cancer data in Scotland (IARC 1985). In this paper, we investigate the power of the rank adjacency statistic to detect spatial clustering when a small number of regions is involved. The investigations were carried out using Monte Carlo simulations, which involved generating patterned/clustered values and computing the power with which the D statistic would detect it. To investigate the effects of region shapes, structure of the regions, and definition of weights, simulations were carried out using two different region shapes, binary and nonhinary weights, and three different lattice structures. The results indicate that in the typical example of considering Canadian total mortality at the electoral district level, the D statistic had adequate power to detect general spatial autocorrelation in twenty-five or more regions. There was an inverse relationship between power and the level of connectedness of the regions, which depends on the weighting function, shape, and arrangement of the regions. The power of the D statistic was also found to compare favorably with that of Moran's I statistic. [source] The University of California, San Francisco Family Alcoholism Study.ALCOHOLISM, Issue 10 2004Background: The University of California, San Francisco (UCSF) Family Alcoholism Study is a project designed to identify genetic loci that influence susceptibility to alcohol dependence and related phenotypes. Evidence supports a substantial genetic contribution to alcoholism susceptibility. However, the genetic epidemiology of alcoholism is complex, and its clinical manifestation is heterogeneous, making phenotype definition and demonstration of linkage difficult. Despite these challenges, some progress has been made toward identifying genes. Methods: The UCSF Family Alcoholism Study used a small family design, focusing primarily on sibling pairs and parent-child trios for linkage and association studies. Alcoholism-related phenotypes were assessed through interview and self-report questionnaires, with a focus on unidimensional and subphenotypical traits. Data-driven approaches to determining the most promising phenotypes for genetic analysis are being used. Both genome-wide scan and candidate gene approaches were used. Results: The study enrolled 2154 individuals from 970 families from December 1995 through January 2003. Test-retest and interrater reliability for clinical data are very good, and power estimates suggest that this study will have adequate power by linkage analysis to detect loci with moderate effects. Design, methods, and sample demographics of the UCSF Family Study are presented, along with intrafamilial correlations for primary diagnostic phenotypes. Conclusions: Plans for genetic analysis, novel approaches to phenotype refinement, and the implications of ascertainment bias for heritability estimates are discussed. [source] Persistent Pain After Breast Cancer SurgeryPAIN MEDICINE, Issue 7 2007B Lau Purpose of the study:, To identify strengths and weaknesses in current studies with a view to carrying out a major multi-center study in Australia. Methods:, The literature was reviewed using standard Medline and Ovid methods. Bibliography of well known key recent papers were used to identify further papers. Results:, Studies evaluating persistent pain after breast cancer surgery have been small and few were prospective controlled studies with adequate power. Like Jung et al[1] we found that the literature was inconsistent in defining chronic pain and differentiating the breast cancer surgery pain syndromes. Marked variations in prior studies are due to differences in: study size (n = 22 to 282 patients), methodology, diagnostic criteria, pain assessment instruments, and distribution of demographic and clinical characteristics in the samples studied. Unfortunately the largest study to date, the ALMANAC Trial (n = 1031) which compared sentinel node biopsy vs "standard axillary dissection" evaluated arm and shoulder function and quality of life, but not pain[2]. From the current literature, it appears that neuropathic breast and arm pain are most common. Widely varying prevalence estimates of different neuropathic pain syndromes have been reported: phantom breast pain (3,44%); intercostobrachial neuralgia (ICBN) (16,39%); ICBN in breast conserving surgery (14,61%); and "neuroma pain" (23,49%). The most established risk factors for surgically related neuropathic pain syndromes are intraoperative nerve trauma, severe acute postoperative pain, and high use of postoperative analgesics[1]. Psychosocial distress is reported to be a risk factor and a consequence of chronic pain[1]. Conclusions:, Well-designed large multi-center studies are required to identify prevalences of various pain types, associated risk factors and treatment success for pain after breast cancer surgery. Such a study is in progress through the collaboration of our group with the Sentinel Node vs Axillary Clearance (SNAC) Study of 1000 women following breast surgery, conducted by the Royal Australian College of Surgeons (RACS). [source] Finding genes in child psychology and psychiatry: When are we going to be there?THE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 10 2005Robert Plomin Background:, The seven papers in this special section chart where we are in the quest for quantitative trait loci (QTLs) in key areas of child psychology and psychiatry such as reading and hyperactivity. But we are not there yet. Methods:, This commentary considers some new developments that are likely to accelerate the journey towards the identification of QTLs. Results:, The single most important factor is the need for very large samples to attain adequate power to detect and replicate QTLs of very small effect size. Another important development is the microarray, which makes it possible to genotype hundreds of thousands of SNPs simultaneously. Using microarrays in association studies allows SNPs across the whole genome to be genotyped. Microarrays will boost power even more when they contain all functional polymorphisms in the genome, including functional non-coding DNA. Conclusions:, Once replicable QTLs are identified in areas such as reading and hyperactivity, the real journey will begin. Future studies will use sets of QTLs as genetic risk indicators in top-down behavioural genomic research, leading to gene-based diagnoses, gene-based treatments tailored to the individual, and early warning systems and interventions. These discoveries will eventually help to prevent or at least ameliorate childhood disorders before they cast their long shadow over development. [source] PRINCIPLES AND THEORIES OF LOCAL GOVERNMENTECONOMIC AFFAIRS, Issue 1 2006Peter A. Watt The role of local government is viewed in the context of the overall role of government per se. A particular advantage of local government lies in its ability to arrange for the provision of local public goods in line with local tastes and preferences. A number of arguments suggest that local governments should be assigned adequate powers of local taxation to finance their expenditure responsibilities rather than having to rely on central government grant. [source] | |||||||||||||