Allocation Status Research Articles

Internal and external validity of cluster randomised trials: systematic review of recent trials

Objectives To assess aspects of the internal validity of recently published cluster randomised trials and explore the reporting of information useful in assessing the external validity of these trials.Design Review...

ANALISIS ALOKASI PENGELUARAN DAN TINGKAT KESEJAHTERAAN KELUARGA (STUDI DI KECAMATAN MEDAN KOTA, SUMATERA UTARA)

In recent years, issues on family welfare are being discussed. One aspect is concerning family welfare indicator and measurement. There are three measures of family welfare, i.e., BKKBN, BPS, and subjective measures. In general, this research was aimed to determine expenditure allocation and family welfare status, and to compare three measurements of welfare status. Cross sectional design and survey method were applied for this research. District of Medan Municipality, with Sudirejo I Sub District, Medan, North Sumatera were chosen purposively as study area. In this sub district 2 areas were chosen at random and 100 families were selected as samples and drawn using Proportional Stratified Random sampling method. Data of family demographic and socioeconomics characteristic, food and non food expenditure, and subjective perception of family welfare were collected for 2 months from Augusts to September 2003. Mann-Whitney test, Chi square, multiple regression, sensitivity and specificity, logistic regression was used to analyze data. The result indicates that the average of non food expenditure of the relatively wealthy family was six times higher than poor family. There was a significant difference of the proportion of food and non food expenditure between poor and wealthy family. Education and income influenced significantly family expenditure. Using BPS criteria as gold standard, the three poverty/welfare indicators (BKKBN, food expenditure and subjective perception) had high sensitivity as many as 100.0. BKKBN and food expenditure criteria were the highest specificity as many as 63.3% and the lowest was subjective perception criteria (22.4%). The welfare determinant based on BPS criteria was the education of family head. The welfare determinant based on BKKBN criteria was family income. The welfare determinant based on food expenditure was the number of family members and income. The welfare determinants based on subjective perception were the education of family head, the age of family head, the perception of price and income. The poverty threshold as much as Rp 230,000.00 based on food expenditure considered the best and was chosen because it could classify poor family more than BKKBN criteria, and the education of family head with less than 13 years (the same as Senior High School level) also represented poverty indicator.

Current Status of Deceased Donor Organ Recovery and Sharing in Korea

The first deceased donor organ (kidney) recovery and transplantation was performed in 1979. Since February 2000, deceased donor organ recovery and allocation have been performed exclusively by the direction of the Korean Network for Organ Sharing (KONOS), the governmental authority for organ transplantation in Korea. Herein, we review the annual incidence of deceased donor occurrence, transplantation statistics, and organ allocation status in the era of KONOS, and discuss about future directions for improved organ transplantation activities in Korea.

Recruitment and standardization of a group of Australian dentists for a multipractice study on dental caries prevention

This introductory paper details the recruitment and standardization of a group of dentists participating in a clinical trial. The trial is being undertaken to determine the cost-effectiveness of a structured preventive programme compared to standard care within private dental practices. We recruited private dental practitioners from a variety of locations in New South Wales (NSW) and the Australian Capital Territory (ACT). We sought to quantify the diagnostic reliability of dentists involved, and to define, quantify, and analyse standard care. This is a multi-centre, clustered randomized controlled trial, where dentists are allocated to an intervention preventive or control group. Recruitment was facilitated with the support of key stakeholders and included oral presentations at divisional meetings of the Australian Dental Association, NSW Branch (ADA). A detailed time-in-motion study of 426 dental procedures was undertaken in order to define the parameters of standard care. The reliability study involved each dentist reading a set of 12 pairs of bitewing radiographs that had been produced and reviewed under standardized conditions. The reliability analysis was undertaken blind to allocation status of the dentist. Recruitment ceased three months into the planned six-month recruitment period, 31 practices having approached the researchers. Eight suburban, five Central Business District (CBD), five rural (in fluoridated communities), and four rural (in non-fluoridated communities) practices have been recruited. Standard care did not differ significantly between intervention and control practices (Mann-Whitney U: z = -0.50; P = 0.6). Diagnostic reliability was substantial (Kappa = 0.79 [range 0.73-0.811 and 0.78 [range 0.72-0.82]) in relation to the intervention and control practices, respectively; P = 0.6. The involvement of private dental practices in research is feasible and well supported by the profession. Standard care does not differ significantly between intervention and control practices. Inter- and intra-observer reliability was substantial, and not statistically different between the two arms of the trial.

Promise or reality? Physical education1 in schools in Europe

Most European governments have committed themselves through legislation to making provision for physical education in schools but they have been either slow or reticent in translating this into action in schools. Consequently, there are perceived deficiencies in school physical education provision, specifically in curriculum time allocation, subject and teacher status, financial, material (inadequacies in facility and equipment supply) and qualified teaching personnel resources and the quality and relevance of the physical education curriculum. The crux of the issue, according to the Council of Europe Deputy General Secretary, is ‘a gap between promise and the reality’. This article explores the theme of ‘promise’ and ‘reality’ by drawing from data generated by a number of international, national and regional surveys and an extended longitudinal literature review, which together highlight the extent of the alleged ‘gap’. It examines recent inter‐governmental and non‐governmental initiatives to address relevant issues and concerns and suggests some policy strategies to assist in converting ‘promises’ into ‘reality’ and so secure a safe future for physical education in schools.

The power of Efron's biased coin design

The power of a statistical test depends on the sample size. Moreover, in a randomized trial where two treatments are compared, the power also depends on the number of assignments of each treatment. We can treat the power as the conditional probability of correctly detecting a treatment effect given a particular treatment allocation status. This paper uses a simple z-test and a t-test to demonstrate and analyze the power function under the biased coin design proposed by Efron in 1971. We numerically show that Efron's biased coin design is uniformly more powerful than the perfect simple randomization.

Platelet-rich-plasmapheresis for minimising peri-operative allogeneic blood transfusion.

Concerns regarding the safety of transfused blood have generated considerable enthusiasm for the use of technologies intended to reduce the use of allogeneic blood (blood from an unrelated donor). Platelet-rich plasmapheresis (PRP) offers an alternative approach to blood conservation. To examine the evidence for the efficacy of PRP in reducing peri-operative allogeneic red blood cell (RBC) transfusion, and the evidence for any effect on clinical outcomes such as mortality and re-operation rates. Studies were identified by: computer searches of MEDLINE, EMBASE, Current Contents, and the Cochrane Library (to June 2001). These searches were supplemented by checking the reference lists of published articles, reports, and reviews. Controlled parallel group trials in which adult patients, scheduled for non-urgent surgery, were randomised to PRP, or to a control group who did not receive the intervention. Main outcomes measured were: the number of patients receiving an allogeneic RBC transfusion, and the amount of RBC transfused. Trial quality was assessed using criteria proposed by Schulz et al. (Schulz 1995) and Jadad et al. (Jadad 1996). Nineteen trials of PRP were identified that reported data for the number of patients exposed to allogeneic RBC transfusion. These trials evaluated a total of 1452 patients. The pooled relative risk (RR) of exposure to allogeneic blood transfusion in those patients randomised to PRP was 0.71 (95%CI: 0.56, 0.90), equating to a relative risk reduction (RRR) of 29%; the average absolute risk reduction (ARR) was 19% (RD = -0.19: 95%CI: -0.29, -0.09). On average, PRP did not significantly reduce the total volume of RBC transfused (weighted mean difference [WMD] = -0.69: 95%CI: -1.93, 0.56 units). Substantial statistical heterogeneity was observed (p < 0.001). Trials provided inadequate data regarding the impact of PRP on morbidity, mortality, and hospital length of stay. The majority of trials were small and of poor methodological quality. Although the results suggest that PRP is effective in reducing allogeneic RBC transfusion in adult patients undergoing elective surgery, there was considerable heterogeneity in treatment effects and the trials were of poor methodological quality. As the majority of trials were unblinded, transfusion practices may have been influenced by knowledge of the patient's allocation status, potentially exaggerating the true magnitude of the beneficial effect of PRP. The available studies provided inadequate data for firm conclusions to be drawn regarding the impact of PRP on clinically important endpoints.

Nutritional status of rural women in relation to their participation in mixed farming in the Tafresh area of Iran.

This study was conducted in the Tafresh area of Iran to assess the dietary patterns, time allocation, and nutritional status of rural women in relation to their participation in mixed farming activities. We selected 75 women from 40 villages by applying a stratified random-sampling technique. Cereals and grains were the major source of energy intake. According to the recommended dietary allowance (RDA) tables of India, the United States, the United Kingdom, and the Food and Agriculture Organization (FAO), the respondents seemed to have no micronutrient and energy deficiencies during the spring season. They spent most of their time and energy on household, animal husbandry, and crop farming activities. According to measurements of body mass index (BMI), the respondents were well nourished. However, despite the high level of BMI, analysis suggested a negative energy balance. Nevertheless, analysis indicated that rural women with negative energy balance spent more time and energy in mixed farming and had a higher level of participation in related activities. Hence, it is evident from the results that the physical contribution of rural women in mixed farming activities has a detrimental effect on their nutritional status, at least during some parts of the year (e.g., spring or summer). Therefore, there is a need to adjust nutritional interventions to improve the sustainability of their food intake and to develop appropriate technologies in mixed farming to alleviate their work burdens.

Nutritional Status of Rural Women in Relation to their Participation in Mixed Farming in the Tafresh Area of Iran

This study was conducted in the Tafresh area of Iran to assess the dietary patterns, time allocation, and nutritional status of rural women in relation to their participation in mixed farming activities. We selected 75 women from 40 villages by applying a stratified random-sampling technique. Cereals and grains were the major source of energy intake. According to the recommended dietary allowance (RDA) tables of India, the United States, the United Kingdom, and the Food and Agriculture Organization (FAO), the respondents seemed to have no micronutrient and energy deficiencies during the spring season. They spent most of their time and energy on household, animal husbandry, and crop farming activities. According to measurements of body mass index (BMI), the respondents were well nourished. However, despite the high level of BMI, analysis suggested a negative energy balance. Nevertheless, analysis indicated that rural women with negative energy balance spent more time and energy in mixed farming and had a higher level of participation in related activities. Hence, it is evident from the results that the physical contribution of rural women in mixed farming activities has a detrimental effect on their nutritional status, at least during some parts of the year (e.g., spring or summer). Therefore, there is a need to adjust nutritional interventions to improve the sustainability of their food intake and to develop appropriate technologies in mixed farming to alleviate their work burdens.

Carbon allocation and sugar status in individual cells of barley leaves affects expression of Sucrose: Fructan 6‐Fructosyltransferase gene

SummaryHeterogeneity of function in plant tissues requires precise regulation of metabolic systems controlling resource allocation at the level of single cells. Differential distribution of metabolites between epidermis, mesophyll and parenchymatous bundle sheath (PBS) cells has already been demonstrated in barley (Hordeum vulgare L.) source leaves and partitioning of sugars in barley leaves has been proven to be highly cell‐type specific. Carbohydrate metabolism of barley leaves induced to accumulate sucrose and fructans was investigated further at the individual cell level, using single cell sampling and analysis techniques. A novel approach using reverse transcription followed by polymerase chain reaction (RT‐PCR) was used to analyse expression of the enzyme Sucrose: Fructan 6‐Fructosyltransferase (6‐SFT) in individual cells of barley leaves. Accumulation of sucrose and the synthesis of fructans were induced by reducing export of sugars from leaves (root cooling), by increasing photosynthesis (high photon fluence rates), or by supplying sugars exogenously. In all cases there was a positive qualitative correlation between the presence of 6‐SFT transcripts and accumulation of fructan and sucrose in both mesophyll and PBS cells.

A high performance memory allocator for object-oriented systems

Object-oriented programming languages tend to allocate and deallocate blocks of memory very frequently. The growing popularity of these languages increases the importance of high-performance memory allocation. For speed and simplicity in memory allocation, the buddy system has been the method of choice for nearly three decades. A software realization incurs the overhead of internal fragmentation and of memory traffic due to splitting and coalescing memory blocks. This paper presents a simple hardware design for buddy-system allocation that takes advantage of the speed of a pure combinational-logic implementation. Two binary trees formed by anding and oring propagate information about the allocation status of blocks and subblocks. They implement a nonbacktracking search for the address of the first free block that is large enough to satisfy a request. Although the buddy system may allocate a block that is much larger than the requested size, the logic that finds a free block can be augmented by a bit-flipper to relinquish the unused portion at the end of the block. This effectively eliminates internal fragmentation. Simulation results show that the buddy system modified in this way uses less memory in most, though not all, programs than the unmodified buddy. Hence, the hardware buddy-system allocator is faster and uses memory more efficiently than the standard software approach.

Plant Allocation, Growth Rate and Successional Status

Theory predicts a negative correlation between root (and stem) allocation and growth rate in enriched environments (RGR max ), but evidence does not consistently support this. There is one possible supporting example from previous research in which root allocation in the field increases during old-field succession at the Cedar Creek Natural History Area, both community wide and for individual species samples, and RGR max declines for some important species. In this study, we confirm that late successional species have lower RGR max for a larger sample of species (n = 28) as well as higher field root allocation. However, root allocation by seedlings does not increase for the late successional species for those same species in the greenhouse in enriched conditions, indeed it declines

Mobile Services--The Impact of the 1979 World Administrative Radio Conference

The decisions of the 1979 World Administrative Radio Conference (WARC-79) will have a major impact on the future development of the Mobile services. This paper summarizes the scope and structure of the Conference and details the changes in the allocations, resolutions, and recommendations which are of interest to the Mobile services. Substantial changes were made in the Maritime and Land-Mobile services and to a lesser degree to the AeronauticalMobile service. Mobile Satellite also attained footnote allocation status in two Regions (2 and 3) and in two countries of Region 1. In most part, the changes made at WARC-79 are beneficial to the future development of the Mobile Services. However, it remains for future specialized conferences to establish the bases for expanding these services in the newly allocated bands.

Mobile Services-The Impact of the 1979 World Administrative Radio Conference

The decisions of the 1979 World Administrative Radio Conference (WARC-79) will have a major impact on the future development of the Mobile services. This paper summarizes the scope and structure of the Conference and details the changes in the allocations, resolutions, and recommendations which are of interest to the Mobile services. Substantial changes were made in the Maritime and Land-Mobile services and to a lesser degree to the Aeronautical-Mobile service. Mobile Satellite also attained footnote allocation status in two Regions (2 and 3) and in two countries of Region 1. In most part, the changes made at WARC-79 are beneficial to the future development of the Mobile services. However, it remains for future specialized conferences to establish the bases for expanding these services in the newly allocated bands.