In this paper, we propose a variable sampling interval Shewhart control chart to monitor the coefficient of variation (CV) squared, denoted by VSI SH-γ 2. The new model overcomes the ARL-biased (average run length) property of the control chart monitoring the CV in a previous study by designing two one-sided charts rather than one two-sided chart. Moreover, the effect of measurement error on the performance of the VSI SH-γ 2 control chart is investigated. The incorrect formula for the distribution of the CV in the presence of measurement error in a former study is fixed. Numerical simulations show that the precision errors and accuracy errors do have negative influences on the VSI SH-γ 2 chart. An appropriate strategy based on the obtained results is suggested to reduce these negative effects.

BackgroundAs in many other low and middle income countries (LIMCs), Vietnam has experienced a major growth in the pharmaceutical industry, with large numbers of pharmacies and drug stores, and increasing drug expenditure per capita over the past decade. Despite regulatory frameworks that have been introduced to control the dispensing and use of prescription-only drugs, including antibiotics, compliance has been reported to be strikingly low particularly in rural parts of Vietnam. This qualitative study aimed to understand antibiotic access and use practices in the community from both supplier and consumer perspectives in order to support the identification and development of future interventions.MethodsThis qualitative study was part of a project on community antibiotic access and use (ABACUS) in six LMICs. The focus was Ba Vi district of Hanoi capital city, where we conducted 16 indepth interviews (IDIs) with drug suppliers, and 16 IDIs and 6 focus group discussions (FGDs) with community members. Drug suppliers were sampled based on mapping of all informal and formal antibiotic purchase or dispensing points in the study area. Community members were identified through local networks and relationships with the field collaborators. All IDIs and FGDs were audio-taped, transcribed and analysed using content analysis.ResultsWe identified a large number of antibiotic suppliers in the locality with widespread infringements of regulatory requirements. Established reciprocal relationships between suppliers and consumers in drug transactions were noted, as was the consumers’ trust in the knowledge and services provided by the suppliers. In addition, antibiotic use has become a habitual choice in most illness conditions, driven by both suppliers and consumers.ConclusionsThis study presents an analysis of the practices of antibiotic access and use in a rural Vietnamese setting. It highlights the interactions between antibiotic suppliers and consumers in the community and identifies possible targets for interventions.

Agricultural land fires have been linked to various and adverse impacts on ecosystems, food security and the agriculture sector. Understanding the patterns and drivers of agricultural land fires is essential for effective agricultural land fire management. The key objectives of this study were to (1) analyze the temporal and spatial patterns of agricultural land fires using satellite remote sensed data, (2) assess a range of environmental conditions that could drive the occurrence of agricultural land fires, (3) determine the best model for predicting agricultural land fires and (4) determine the relative contribution of each environmental condition variable on the best predictive model. We used both univariate and multivariate regressions for the fire prediction capability of four independent environmental conditions (fuel, weather, topographic and anthropogenic). Analysis of historical satellite data revealed that agricultural land fires were more frequent than forested land fires. Our analyses also revealed that fuel condition was the most important variable for predicting agricultural land fires followed by weather, topographic and anthropogenic conditions. This study provides a novel multivariate model for predicting agricultural land fires that harbors the potential to improve agricultural land fire management and reduce fire risk within the agricultural sector.