Productive Efficiency in Agriculture: Corn Production in Mexico

Using a stochastic production frontier model and data for 2002 from a representative sample of Mexican rural households, in this paper we first study empirically whether or not small and medium farmers produce corn efficiently. The results show that corn production is inefficient, nation-wide and for both commercial and subsistence farmers. Our findings also show that this is even more so for subsistence producers and for the Center and the South-southeast regions of rural Mexico. In addition, we find that subsistence farmers use less prod uctive inputs (seeds and agrochemicals) with respect to commercial farmers. Based on these results, we then apply a regression model to inquire about the factors explaining inefficiency. We get that farmers facing natural disasters, that produce corn for subsistence using diverse seed varieties of the grain in plots with less than 1 hectare and indigenous, are more inefficient than other farmers. The results also indicate that households located in communities with marketing facilities and that have benefited from infrastructural investments, produce corn in a less inefficient manner. The detailed nature of the data used allows us to have results that differentiate rural regions as well as commercial and subsistence corn producers, and hence, to suggest focalized policies for rural development.Crop Production/Industries, Productivity Analysis,

Copula Based Stochastic Weather Generator as an Application for Crop Growth Models and Crop Insurance

Stochastic Weather Generators (SWG) try to reproduce the stochastic patterns of climatological variables characterized by high dimensionality, non-normal probability density functions and non-linear dependence relationships. However, conventional SWGs usually typify weather variables with unjustified probability distributions assuming linear dependence between variables. This research proposes an alternative SWG that introduces the advantages of the Copula modeling into the reproduction of stochastic weather patterns. The Copula based SWG introduces more flexibility allowing researcher to model non-linear dependence structures independently of the marginals involved, also it is able to model tail dependence, which results in a more accurate reproduction of extreme weather events. Statistical tests on weather series simulated by the Copula based SWG show its capacity to replicate the statistical properties of the observed weather variables, along with a good performance in the reproduction of the extreme weather events. In terms of its use in crop growth models for the ratemaking process of new insurance schemes with no available historical yield data, the Copula based SWG allows one to more accurately evaluate the risk. The use of the Copula based SWG for the simulation of yields results in higher crop insurance premiums from more frequent extreme weather events, while the use of the conventional SWG for the yield estimation could lead to an underestimation of risks

Stages of change: Strategies to promote use of a Pediatric Early Warning System in resource-limited pediatric oncology centers.

BackgroundPediatric Early Warning Systems (PEWS) assist early detection of clinical deterioration in hospitalized children with cancer. Relevant to successful PEWS implementation, the stages of change model characterizes stakeholder support for PEWS based on willingness and effort to adopt the new practice.MethodsAt five resource-limited pediatric oncology centers in Latin America, semi-structured interviews were conducted with 71 hospital staff involved in PEWS implementation. Purposive sampling was used to select centers requiring variable time to complete PEWS implementation, with low-barrier centers (3-4 months) and high-barrier centers (10-11 months). Interviews were conducted in Spanish, professionally transcribed, and translated into English. Thematic content analysis explored stage of change with constant comparative analysis across stakeholder types and study sites.ResultsParticipants identified six interventions (training, incentives, participation, evidence, persuasion, and modeling) and two policies (environmental planning and mandates) as effective strategies used by implementation leaders to promote stakeholder progression through stages of change. Key approaches involved presentation of evidence demonstrating PEWS effectiveness, persuasion and incentives addressing specific stakeholder interests, enthusiastic individuals serving as models for others, and policies enforced by hospital directors facilitating habitual PEWS use. Effective engagement targeted hospital directors during early implementation phases to provide programmatic legitimacy for clinical staff.ConclusionThis study identifies strategies to promote adoption and maintained use of PEWS, highlighting the importance of tailoring implementation strategies to the motivations of each stakeholder type. These findings can guide efforts to implement PEWS and other evidence-based practices that improve childhood cancer outcomes in resource-limited hospitals

Impact of hospital characteristics on implementation of a Pediatric Early Warning System in resource-limited cancer hospitals

BackgroundPediatric Early Warning Systems (PEWS) aid in identification of deterioration in hospitalized children with cancer but are underutilized in resource-limited settings. Proyecto EVAT is a multicenter quality improvement (QI) collaborative in Latin America to implement PEWS. This study investigates the relationship between hospital characteristics and time required for PEWS implementation.MethodsThis convergent mixed-methods study included 23 Proyecto EVAT childhood cancer centers; 5 hospitals representing quick and slow implementers were selected for qualitative analysis. Semi-structured interviews were conducted with 71 stakeholders involved in PEWS implementation. Interviews were recorded, transcribed and translated to English, then coded using a priori and novel codes. Thematic content analysis explored the impact of hospital characteristics and QI experience on time required for PEWS implementation and was supplemented by quantitative analysis exploring the relationship between hospital characteristics and implementation time.ResultsIn both quantitative and qualitative analysis, material and human resources to support PEWS significantly impacted time to implementation. Lack of resources produced various obstacles that extended time necessary for centers to achieve successful implementation. Hospital characteristics, such as funding structure and type, influenced PEWS implementation time by determining their resource-availability. Prior hospital or implementation leader experience with QI, however, helped facilitate implementation by assisting implementers predict and overcome resource-related challenges.ConclusionsHospital characteristics impact time required to implement PEWS in resource-limited childhood cancer centers; however, prior QI experience helps anticipate and adapt to resource challenges and more quickly implement PEWS. QI training should be a component of strategies to scale-up use of evidence-based interventions like PEWS in resource-limited settings

Familial hypercholesterolaemia in children and adolescents from 48 countries: a cross-sectional study

Background: Approximately 450 000 children are born with familial hypercholesterolaemia worldwide every year, yet only 2·1% of adults with familial hypercholesterolaemia were diagnosed before age 18 years via current diagnostic approaches, which are derived from observations in adults. We aimed to characterise children and adolescents with heterozygous familial hypercholesterolaemia (HeFH) and understand current approaches to the identification and management of familial hypercholesterolaemia to inform future public health strategies. Methods: For this cross-sectional study, we assessed children and adolescents younger than 18 years with a clinical or genetic diagnosis of HeFH at the time of entry into the Familial Hypercholesterolaemia Studies Collaboration (FHSC) registry between Oct 1, 2015, and Jan 31, 2021. Data in the registry were collected from 55 regional or national registries in 48 countries. Diagnoses relying on self-reported history of familial hypercholesterolaemia and suspected secondary hypercholesterolaemia were excluded from the registry; people with untreated LDL cholesterol (LDL-C) of at least 13·0 mmol/L were excluded from this study. Data were assessed overall and by WHO region, World Bank country income status, age, diagnostic criteria, and index-case status. The main outcome of this study was to assess current identification and management of children and adolescents with familial hypercholesterolaemia. Findings: Of 63 093 individuals in the FHSC registry, 11 848 (18·8%) were children or adolescents younger than 18 years with HeFH and were included in this study; 5756 (50·2%) of 11 476 included individuals were female and 5720 (49·8%) were male. Sex data were missing for 372 (3·1%) of 11 848 individuals. Median age at registry entry was 9·6 years (IQR 5·8-13·2). 10 099 (89·9%) of 11 235 included individuals had a final genetically confirmed diagnosis of familial hypercholesterolaemia and 1136 (10·1%) had a clinical diagnosis. Genetically confirmed diagnosis data or clinical diagnosis data were missing for 613 (5·2%) of 11 848 individuals. Genetic diagnosis was more common in children and adolescents from high-income countries (9427 [92·4%] of 10 202) than in children and adolescents from non-high-income countries (199 [48·0%] of 415). 3414 (31·6%) of 10 804 children or adolescents were index cases. Familial-hypercholesterolaemia-related physical signs, cardiovascular risk factors, and cardiovascular disease were uncommon, but were more common in non-high-income countries. 7557 (72·4%) of 10 428 included children or adolescents were not taking lipid-lowering medication (LLM) and had a median LDL-C of 5·00 mmol/L (IQR 4·05-6·08). Compared with genetic diagnosis, the use of unadapted clinical criteria intended for use in adults and reliant on more extreme phenotypes could result in 50-75% of children and adolescents with familial hypercholesterolaemia not being identified. Interpretation: Clinical characteristics observed in adults with familial hypercholesterolaemia are uncommon in children and adolescents with familial hypercholesterolaemia, hence detection in this age group relies on measurement of LDL-C and genetic confirmation. Where genetic testing is unavailable, increased availability and use of LDL-C measurements in the first few years of life could help reduce the current gap between prevalence and detection, enabling increased use of combination LLM to reach recommended LDL-C targets early in life

The Impact of Food Price Shocks on Consumption and Nutritional Patterns of Urban Mexican Households

During the 2000s, recurrent food price shocks in Mexico modified consumption and nutritional patterns of households. This research quantifies the impacts of food price shocks on the purchase of nutrients and on the weight gain of children in urban Mexican households. We find differentiated patterns of food consumption across income quintiles, which result in heterogeneous effects of price shocks on the purchase of nutrients and on weight gain according to age and sex in children. In particular, cereal price shocks are more detrimental and more regressive than price shocks on other categories like meats, vegetables or beverages

Effectiveness of Weather Derivatives as a Cross-Hedging Instrument against Climate Change: The Cases of Reservoir Water Allocation Management in Guanajuato, Mexico and Lambayeque, Peru

Ongoing climate change will increase competition for water. Diversified demand for water-in contrast with the rigid design of water systems, institutions and infrastructure-could hinder the implementation of adaptation policies in water management for Latin American countries. In this context, weather derivatives are proposed as a complementary mechanism for the successful adoption of more efficient water allocations in irrigation districts. Weather derivatives spread risks and incorporate a better understanding of climate system behavior, strengthening irrigation districts¿ ability to deal with water availability and demand. The model uses a dynamic water resource allocation model, historical precipitation and Intergovernmental Panel on Climate Change (IPCC) scenarios to find optimal water allocation strategies for the baseline scenario and in the presence of climate change. This analysis is applied to two irrigation districts in Latin America: one in Mexico and the other in Peru, with their corresponding particularities and results.