Walter W. Tooley Papers

MS038-201

Un análisis multinivel de población y deforestación en el Parque Nacional Sierra de Lacandón (Petén, Guatemala)

Este estudio examina los factores demográficos asociados con la deforestación en el Parque Nacional Sierra de Lacandón (PNSL), Guatemala, utilizando un análisis de regresión multinivel. Más del 10% del PNSL ha sido deforestado desde mediados de la década de 1980, a causa del crecimiento demográfico de la población campesina y su subsiguiente manejo de la tierra. Utilizando un análisis de regresión múltiple de dos niveles, este estudio examina datos demográficos y otras características de los hogares para explicar variaciones en el bosque roturado entre 241 fincas agrícolas en ocho comunidades en el PNSL. Esta metodología, novedosa en el estudio de uso del suelo en los trópicos, toma en cuenta la variación espacial entre comunidades, así como entre hogares. Al usar modelos de multinivel, se puede llegar a resultados mejores sobre los impactos de los factores, tanto a nivel de comunidad como a nivel de hogar sobre la deforestación, con implicaciones más adecuadas para políticas de desarrollo.Aquest estudi examina els factors demogràfics associats amb la desforestació al Parc Nacional Sierra de Lacandon (PNSL), Guatemala, mitjançant una anàlisi de regressió multinivell. Més del 10 % del PNSL ha estat desforestat des de la meitat de la dècada de 1980, com a conseqüència del creixement demogràfic i les pràctiques de gestió agrícola. Utilitzant una anàlisi de regressió múltiple de dos nivells, aquest estudi examina dades demogràfiques i unes altres característiques de les llars per explicar variacions en el bosc artigat entre 241 finques agrícoles en vuit comunitats al PNSL. Aquesta metodologia té en compte la variació especial entre comunitats i entre llars, i abans no havia estat mai aplicada als tròpics. El model de regressió multinivell pot ajudar a explicar millor els impactes de factors propis de les comunitats i de les llars en la desforestació, per tant, pot contribuir a millorar les polítiques de desenvolupament.Cette étude a examiné les facteurs démographiques associés au phénomène de déforestation du Parc National Sierra de Lacandón (PNSL, Guatemala) en utilisant une analyse de régression multi-niveau. Depuis le milieu des années 1980, plus de 10 % du PNSL a été déboisé par la croissance démographique de la population rurale, son besoin en surface et l'utilisation variée de la terre. En utilisant une analyse de régression multiple de deux niveaux, cette étude examine des données démographiques et plusieurs caractéristiques liées aux exploitations, dans le but d'expliquer les variations dans le parc défriché entre 241 propriétés agricoles dans huit communautés du PNSL. Cette méthodologie, nouvelle dans l'étude de l'usage du sol dans les tropiques, prend en compte la variation spatiale entre des communautés ainsi que des exploitations. En utilisant ces modèles de multi-niveaux, on peut arriver à de meilleurs résultats concernant les impacts des facteurs au niveau des communautés et des exploitations concernant la déforestation, avec des résultats plus adapatées pour les politiques de développement.The paper examines depopulation factors associated with deforestation in the Natural park of the Sierra de Lacandón (PNSL), using multi-level regresión analysis. More than 10 percent of the park area has been deforested since the mid 1980s because of rural population growth and agricultural practices. By means of a two-level regression analysis the study use dem ographic and other household data to explain variations in deforested land in 241 agricultural estates in 8 communities of the PNSL. The methodology, not applied before in the tropics, takes into account spatial variations between communities and households. Multilvel regression allows for better results on the impacts of socioeconomic factors on deforestation, both at the community and at the household levels with important implications for development policies

Comparison of two different physical activity monitors

<p>Abstract</p> <p>Background</p> <p>Understanding the relationships between physical activity (PA) and disease has become a major area of research interest. Activity monitors, devices that quantify free-living PA for prolonged periods of time (days or weeks), are increasingly being used to estimate PA. A range of different activity monitors brands are available for investigators to use, but little is known about how they respond to different levels of PA in the field, nor if data conversion between brands is possible.</p> <p>Methods</p> <p>56 women and men were fitted with two different activity monitors, the Actigraph™ (Actigraph LLC; AGR) and the Actical™ (Mini-Mitter Co.; MM) for 15 days. Both activity monitors were fixed to an elasticized belt worn over the hip, with the anterior and posterior position of the activity monitors randomized. Differences between activity monitors and the validity of brand inter-conversion were measured by <it>t</it>-tests, Pearson correlations, Bland-Altman plots, and coefficients of variation (CV).</p> <p>Results</p> <p>The AGR detected a significantly greater amount of daily PA (216.2 ± 106.2 vs. 188.0 ± 101.1 counts/min, P < 0.0001). The average difference between activity monitors expressed as a CV were 3.1 and 15.5% for log-transformed and raw data, respectively. When a conversion equation was applied to convert datasets from one brand to another, the differences were no longer significant, with CV's of 2.2 and 11.7%, log-transformed and raw data, respectively.</p> <p>Conclusion</p> <p>Although activity monitors predict PA on the same scale (counts/min), the results between these two brands are not directly comparable. However, the data are comparable if a conversion equation is applied, with better results for log-transformed data.</p

Lymphatic Filariasis Control in Tanzania: Effect of Six Rounds of Mass Drug Administration with Ivermectin and Albendazole on Infection and Transmission.

Control of lymphatic filariasis (LF) in most countries of sub-Saharan Africa is based on annual mass drug administration (MDA) with a combination of ivermectin and albendazole, in order to interrupt transmission. We present findings from a detailed study on the effect of six rounds of MDA with this drug combination as implemented by the National Lymphatic Filariasis Elimination Programme (NLFEP) in a highly endemic rural area of north-eastern Tanzania.\ud The effect of treatment on transmission and human infection was monitored in a community- and a school-based study during an 8-year period (one pre-intervention and 7 post-intervention years) from 2003 to 2011. Before intervention, 24.5% of the community population had microfilariae (mf) in the blood, 53.3% had circulating filarial antigens (CFA) and 78.9% had specific antibodies to the recombinant filarial antigen Bm14. One year after the sixth MDA, these values had decreased considerably to 2.7%, 19.6% and 27.5%, respectively. During the same period, the CFA prevalence among new intakes of Standard 1 pupils in 10 primary schools decreased from 25.2% to 5.6%. In line with this, transmission by the three vectors (Anopheles gambiae, An. funestus and Culex quinquefasciatus) as determined by dissection declined sharply (overall vector infectivity rate by 99.3% and mean monthly transmission potential by 99.2% between pre-intervention and fifth post-intervention period). A major shift in vector species composition, from predominantly anopheline to almost exclusively culicine was observed over the years. This may be largely unrelated to the MDAs but may have important implications for the epidemiology of LF in the area. Six MDAs caused considerable decrease in all the measured indices for transmission and human infection. In spite of this, indices were still relatively high in the late period of the study, and it may take a long time to reach the recommended cut-off levels for interruption of transmission unless extra efforts are made. These should include increased engagement of the target population in the control activities, to ensure higher treatment coverage. It is expected that the recent initiative to distribute insecticide impregnated bed nets to every household in the area will also contribute towards reaching the goal of successful LF elimination

Clinical outcomes resulting from telemedicine interventions: a systematic review

BACKGROUND: The use of telemedicine is growing, but its efficacy for achieving comparable or improved clinical outcomes has not been established in many medical specialties. The objective of this systematic review was to evaluate the efficacy of telemedicine interventions for health outcomes in two classes of application: home-based and office/hospital-based. METHODS: Data sources for the study included deports of studies from the MEDLINE, EMBASE, CINAHL, and HealthSTAR databases; searching of bibliographies of review and other articles; and consultation of printed resources as well as investigators in the field. We included studies that were relevant to at least one of the two classes of telemedicine and addressed the assessment of efficacy for clinical outcomes with data of reported results. We excluded studies where the service did not historically require face-to-face encounters (e.g., radiology or pathology diagnosis). All included articles were abstracted and graded for quality and direction of the evidence. RESULTS: A total of 25 articles met inclusion criteria and were assessed. The strongest evidence for the efficacy of telemedicine in clinical outcomes comes from home-based telemedicine in the areas of chronic disease management, hypertension, and AIDS. The value of home glucose monitoring in diabetes mellitus is conflicting. There is also reasonable evidence that telemedicine is comparable to face-to-face care in emergency medicine and is beneficial in surgical and neonatal intensive care units as well as patient transfer in neurosurgery. CONCLUSIONS: Despite the widespread use of telemedicine in virtually all major areas of health care, evidence concerning the benefits of its use exists in only a small number of them. Further randomized controlled trials must be done to determine where its use is most effective

Impact of Splenectomy on Thrombocytopenia, Chemotherapy, and Survival in Patients with Unresectable Pancreatic Cancer

Patients with unresectable pancreatic cancer (PDAC) or endocrine tumors (PET) often develop splenic vein thrombosis, hypersplenism, and thrombocytopenia which limits the administration of chemotherapy. From 2001 to 2009, 15 patients with recurrent or unresectable PDAC or PET underwent splenectomy for hypersplenism and thrombocytopenia. The clinical variables of this group of patients were analyzed. The overall survival of patients with PDAC was compared to historical controls. Of the 15 total patients, 13 (87%) had PDAC and 2 (13%) had PET. All tumors were either locally advanced (n = 6, 40%) or metastatic (n = 9, 60%). The platelet counts significantly increased after splenectomy (p &lt; 0.01). All patients were able to resume chemotherapy within a median of 11.5 days (range 6–27). The patients with PDAC had a median survival of 20 months (range 4–67) from the time of diagnosis and 10.6 months (range 0.6–39.8) from the time of splenectomy. Splenectomy for patients with unresectable PDAC or PET who developed hypersplenism and thrombocytopenia that limited the administration of chemotherapy, significantly increased platelet counts, and led to resumption of treatment in all patients. Patients with PDAC had better disease-specific survival as compared to historical controls

Support for immunization registries among parents of vaccinated and unvaccinated school-aged children: a case control study

BACKGROUND: Immunizations have reduced childhood vaccine preventable disease incidence by 98–100%. Continued vaccine preventable disease control depends on high immunization coverage. Immunization registries help ensure high coverage by recording childhood immunizations administered, generating reminders when immunizations are due, calculating immunization coverage and identifying pockets needing immunization services, and improving vaccine safety by reducing over-immunization and providing data for post-licensure vaccine safety studies. Despite substantial resources directed towards registry development in the U.S., only 48% of children were enrolled in a registry in 2004. Parental attitudes likely impact child participation. Consequently, the purpose of this study was to assess the attitudes of parents of vaccinated and unvaccinated school-aged children regarding: support for immunization registries; laws authorizing registries and mandating provider reporting; opt-in versus opt-out registry participation; and financial worth and responsibility of registry development and implementation. METHODS: A case control study of parents of 815 children exempt from school vaccination requirements and 1630 fully vaccinated children was conducted. Children were recruited from 112 elementary schools in Colorado, Massachusetts, Missouri, and Washington. Surveys administered to the parents, asked about views on registries and perceived utility and safety of vaccines. Parental views were summarized and logistic regression models compared differences between parents of exempt and vaccinated children. RESULTS: Surveys were completed by 56.1% of respondents. Fewer than 10% of parents were aware of immunization registries in their communities. Among parents aware of registries, exempt children were more likely to be enrolled (65.0%) than vaccinated children (26.5%) (p value = 0.01). A substantial proportion of parents of exempt children support immunization registries, particularly if registries offer choice for participation. Few parents of vaccinated (6.8%) and exempt children (6.7%) were aware of laws authorizing immunization registries. Support for laws authorizing registries and requiring health care providers to report to registries was more common among parents of vaccinated than exempt children. Most parents believed that the government, vaccine companies or insurance companies should pay for registries. CONCLUSION: Parental support for registries was relatively high. Parental support for immunization registries may increase with greater parental awareness of the risks of vaccine preventable diseases and utility of vaccination

Reducing demand for overexploited wildlife products: Lessons from systematic reviews from outside conservation science

Abstract: Conservationists have long sought to reduce consumer demand for products from overexploited wildlife species. Health practitioners have also begun calling for reductions in the wildlife trade to reduce pandemic risk. Most wildlife‐focused demand reduction campaigns have lacked rigorous evaluations and thus their impacts remain unknown. There is thus an urgent need to review the evidence from beyond conservation science to inform future demand‐reduction efforts. We searched for systematic reviews of interventions that aimed to reduce consumer demand for products that are harmful (e.g., cigarettes and illicit drugs). In total, 41 systematic reviews were assessed, and their data extracted. Mass‐media campaigns and incentive programs were, on average, ineffective. While advertising bans, social marketing, and location bans were promising, there was insufficient robust evidence to draw firm conclusions. In contrast, the evidence for the effectiveness of norm appeals and risk warnings was stronger, with some caveats

Reducing demand for overexploited wildlife products: Lessons from systematic reviews from outside conservation science

Abstract: Conservationists have long sought to reduce consumer demand for products from overexploited wildlife species. Health practitioners have also begun calling for reductions in the wildlife trade to reduce pandemic risk. Most wildlife‐focused demand reduction campaigns have lacked rigorous evaluations and thus their impacts remain unknown. There is thus an urgent need to review the evidence from beyond conservation science to inform future demand‐reduction efforts. We searched for systematic reviews of interventions that aimed to reduce consumer demand for products that are harmful (e.g., cigarettes and illicit drugs). In total, 41 systematic reviews were assessed, and their data extracted. Mass‐media campaigns and incentive programs were, on average, ineffective. While advertising bans, social marketing, and location bans were promising, there was insufficient robust evidence to draw firm conclusions. In contrast, the evidence for the effectiveness of norm appeals and risk warnings was stronger, with some caveats