Chasms in Achievement of Recommended Diabetes Care among Geographic Regions in Korea

BACKGROUND: Although effective care for type 2 diabetes (T2DM) is well known, considerable inadequate care has been still existed. Variations in achievement of the recommended quality indicators inT2DM care among small areas are not well known in Korea. This study examined the quality of care T2DM care and its geographical variations. METHODS: We used the national health insurance database and national health screening database. Seven quality indicators were used to evaluate continuity of care (medication possession ratio), process of care (hemoglobin A1c test, lipid profile, microalbuminuria test, and eye examination), and intermediate outcome (blood pressure control, and low-density lipoprotein control). Crude and age-standardized proportions were calculated for each 252 districts in Korea. RESULTS: All quality indicators failed to achieve the recommended level. Only about 3% and 15% of the patients underwent eye examination and microalbuminuria test, respectively. Other indicators ranged from 48% to 68%. Wide variation in the quality existed among districts and indicators. Eye examination and microalbuminuria test varied the most showing tenfold (0.9%–9.2%) and fourfold (6.3%–28.9%) variation by districts, respectively. There were 32.4 and 42.7 percentage point gap between the best and the worst districts in hemoglobin A1c test and blood pressure control, respectively. CONCLUSION: Considerable proportion of T2DM patients were not adequately managed and quality of care varied substantially district to district. To improve the quality of diabetes care, it is necessary to identify the poor performance areas and establish a well-coordinated care system tailored to the need of the district.

Social determinants of tuberculosis via a zero-inflated model in small areas of a city in Southeastern Brazil

Abstract INTRODUCTION: This study aimed to analyze social factors involved in the spatial distribution and under-reporting of tuberculosis (TB) in the city of Vitória, Espírito Santo State, Brazil. METHODS: This was an ecological study of the reported cases of TB between 2009 and 2011, according to census tracts. The outcome was TB incidence for the study period and the variables of exposure were proportions of literacy, inhabitants with an income of up to half the minimum monthly wage (MMW), and inhabitants associated with sewer mains or with access to safe drinking water. We used a zero-inflated process, zero-inflated negative binomial regression (ZINB), and selected an explanatory model based on the Akaike Information Criterion (AIC). RESULTS: A total of 588 cases of tuberculosis were reported in Vitória during the study period, distributed among 223 census tracts (38.6%), with 354 (61.4%) tracts presenting zero cases. In the ZINB model, the mean value of p i was 0.93, indicating that there is a 93% chance that an observed false zero could be due to sub-notification. CONCLUSIONS: It is important to prioritize areas exhibiting determinants that influence the occurrence of TB in the municipality of Vitória. The zero-inflated model can be useful to the public health sector since it identifies the percentage of false zeros, generating an estimate of the real epidemiological condition of TB in Vitória.

Geographical Variations and Trends in Major Cancer Incidences throughout Korea during 1999-2013 / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: We aimed to describe the temporal trends and district-level geographical variations in cancer incidences throughout Korea during 1999-2013. MATERIALS AND METHODS: Data were obtained from the Korean National Cancer Incidence Database. We calculated the age-standardized cumulative cancer incidences according to sex and geographical region (metropolitan cities, provinces, and districts) for three 5-year periods (1999-2003, 2004-2008, and 2009-2013). Each quintile interval contained the same number of regions. Disease maps were created to visualize regional differences in the cancer incidences. RESULTS: Substantial differences in cancer incidences were observed according to district and cancer type. The largest variations between geographical regions were found for thyroid cancer among both men and women. There was little variation in the incidences of stomach, colorectal, and lung cancer according to geographical region. Substantially elevated incidences of specific cancers were observed in Jeollanam-do (thyroid); Daejeon (colorectum); Jeollanam-do, Gyeongsangbuk-do, and Chungcheongbuk-do (lung); Seocho-gu, Gangnam-gu and Seongnam, Bundang-gu (breast and prostate); Chungcheong and Gyeongsang provinces (stomach); Ulleung-gun and the southern districts of Gyeongsangnam-do and Jeollanam-do (liver); and along the Nakdonggang River (gallbladder and biliary tract). CONCLUSION: Mapping regional cancer incidences in Korea allowed us to compare the results according to geographical region. Our results may facilitate the development of infrastructure for systematic cancer incidence monitoring, which could promote the planning and implementation of region-specific cancer management programs.

Evaluation of Geographic Indices Describing Health Care Utilization / 예방의학회지

OBJECTIVES: The accurate measurement of geographic patterns of health care utilization is a prerequisite for the study of geographic variations in health care utilization. While several measures have been developed to measure how accurately geographic units reflect the health care utilization patterns of residents, they have been only applied to hospitalization and need further evaluation. This study aimed to evaluate geographic indices describing health care utilization. METHODS: We measured the utilization rate and four health care utilization indices (localization index, outflow index, inflow index, and net patient flow) for eight major procedures (coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, surgery after hip fracture, knee replacement surgery, caesarean sections, hysterectomy, computed tomography scans, and magnetic resonance imaging scans) according to three levels of geographic units in Korea. Data were obtained from the National Health Insurance database in Korea. We evaluated the associations among the health care utilization indices and the utilization rates. RESULTS: In higher-level geographic units, the localization index tended to be high, while the inflow index and outflow index were lower. The indices showed different patterns depending on the procedure. A strong negative correlation between the localization index and the outflow index was observed for all procedures. Net patient flow showed a moderate positive correlation with the localization index and the inflow index. CONCLUSIONS: Health care utilization indices can be used as a proxy to describe the utilization pattern of a procedure in a geographic unit.

ESTUDIOS EPIDEMIOLÓGICOS EN ÁREAS PEQUEÑAS: HERRAMIENTAS PARA ANALIZAR LA CONTAMINACIÓN AMBIENTAL Y SUS EFECTOS EN SALUD A ESCALA LOCAL / EPIDEMIOLOGICAL STUDIES IN SMALL AREAS: TOOLS FOR ANALYZING ENVIRONMENTAL POLLUTION AND ITS HEALTH EFFECTS ON LOCAL SCALE

La creciente contaminación de origen antrópico ha generado preocupación mundial por sus potenciales efectos perjudiciales para la salud humana. Ante esta necesidad de investigación, los estudios epidemiológicos espaciales en áreas pequeñas se presentan como un abordaje sencillo y eficiente, que utiliza datos recopilados de manera rutinaria para analizarlos mediante técnicas estadísticas sofisticadas, ofreciendo herramientas para estudiar asociaciones epidemiológicas a escala local. En este trabajo se presenta una revisión de las generalidades y los elementos metodológicos y estadísticos de estos estudios, con algunos ejemplos de estudios publicados en las dos últimas décadas, y se discuten algunos puntos relevantes.

The increasing anthropogenic pollution has generated worldwide concern about potential adverse effects on human health. Given this need for research, spatial epidemiological studies in small areas are presented as a simple and efficient approach, using routinely collected data to be analyzed using sophisticated statistical techniques, providing tools to study locally epidemiological associations. A review of generalities and methodological and statistical elements of these studies is presented in this article with some examples of studies published in the last two decades, and a brief discussion about some relevant issues.

Estimação da mortalidade infantil nos municípios brasileiros / Infant mortality estimation in Brazilian municipalities

A indisponibilidade de dados vitais completos e confiáveis compromete a avaliação de ações de saúde. Monitorar o grau de cobertura dos eventos e a adequação dos dados informados são procedimentos importantes para a construção de indicadores fidedignos da situação de saúde. Com a valorização das informações desagregadas por município, tem sido incentivada a utilização dos dados dos Sistemas de Informações Vitais do Ministério da Saúde. Entretanto, limitações relacionadas à consistência e à cobertura destas informações, dificultam a estimação da mortalidade infantil em alguns municípios brasileiros. A presente tese teve por objetivo propor uma metodologia de estimação do Coeficiente de Mortalidade Infantil (CMI) para os municípios brasileiros que considerasse a subenumeração de óbitos e o porte populacional bem como estimar fatores de correção para os óbitos informados ao Sistema de Informações sobre Mortalidade (SIM) na esfera municipal.A tese está apresentada na forma de três artigos. No primeiro, foi proposto método para estimação do CMI por município, levando em consideração a subenumeração de óbitos e o porte populacional do município. O método foi desenvolvido a partir da estimação de fatores de correção de óbitos e nascidos vivos por município, no triênio 2009-2011, através de indicadores construídos para caracterizar a cobertura das informações vitais. Foi proposto um procedimento para verificar se o número corrigido de óbitos infantis atingia o valor mínimo esperado. No caso de insuficiência do fator de correção, foram usados os valores preditos de uma regressão multivariada para estimar o CMI. Diante dos achados da presente tese, pode-se verificar que ainda existem grandes problemas a superar, como as persistentes desigualdades de acesso à assistência de saúde e à omissão da informação de óbito, que compromete o dimensionamento da realidade local. Embora os avanços conseguidos na informação dos dados vitais no Brasil sejam amplamente reconhecidos, os resultados mostram que persiste a dificuldade de alcançar os municípios rurais e remotos, que ainda não dispõem de informações vitais adequadas.

The unavailability of complete and reliable vital data restricts the evaluation of health actions. Monitoring the level of coverage of the events and the adequacy of informed data areimportant procedures for the construction of reliable indicators of health status. In late years,municipality data have been valued and the use of the Vital Information Systems of the Ministryof Health has been encouraged. However, limitations related to consistency and coverage ofthis information make it difficult to estimate child mortality in some municipalities. This thesis aimed to propose an estimation methodology of the infant mortality rate (IMR) in Brazilian municipalities by considering the underreporting of deaths and municipality population size, as well as to estimate correction factors for deaths informed to the Mortality Information System at the municipality level. The thesis is presented in the form of three articles. In the first one, we proposed amethod for infant mortality estimation by municipality, taking into account the underreportingof deaths and population size of the municipality. The method was developed from the estimation of correction factors of live births and deaths by municipality in the period 2009-2011, based on indicators that characterize the level of coverage of vital information. Aprocedure was proposed to verify that if the corrected number of infant deaths reached the minimum expected value according to the population size of the municipality. In case of insufficiency of the correction factor, we used the predicted values of a multivariate regressionto estimate the IMR. Given the findings of this thesis, it can be seen that there are still major problems toovercome, such as persistent inequalities in access to health care and the failure of death information, which limits scaling the real local situation. Although improvements made in information of vital data in Brazil are widely recognized, the results show that our greatest challenge is to reach the rural and remote municipalities, which do not yet have adequate vital information.

Análise espacial de dados de contagem com excesso de zeros aplicado ao estudo da incidência de dengue em Campinas, São Paulo, Brasil / Spatial analysis of counting data with excess zeros applied to the study of dengue incidence in Campinas, São Paulo State, Brazil / Análisis espacial de datos de conteo con exceso de ceros, aplicado al estudio de la incidencia de dengue en Campinas, São Paulo, Brasil

Resumo: A incidência de dengue ocorre predominantemente em áreas urbanas das cidades. Identificar o padrão de distribuição espacial da doença no nível local contribui na formulação de estratégias de controle e prevenção da doença. A análise espacial de dados de contagem para pequenas áreas comumente viola as suposições dos modelos tradicionais de Poisson, devido à quantidade excessiva de zeros. Neste estudo, comparou-se o desempenho de quatro modelos de contagem utilizados no mapeamento de doenças: Poisson, Binomial negativa, Poisson inflacionado de zeros e Binomial negativa inflacionado de zeros. Os métodos foram comparados em um estudo de simulação. Os modelos analisados no estudo de simulação foram aplicados em um estudo ecológico espacial, aos dados de dengue agregados por setores censitários, do Município de Campinas, São Paulo, Brasil, em 2007. A análise espacial foi conduzida por modelos hierárquicos bayesianos. O modelo de Poisson inflacionado de zeros apresentou melhor desempenho para estimar o risco relativo de incidência de dengue nos setores censitários.

Abstract: Dengue incidence occurs predominantly within city limits. Identifying spatial distribution of the disease at the local level helps formulate strategies to control and prevent the disease. Spatial analysis of counting data for small areas commonly violates the assumptions of traditional Poisson models due to the excessive amount of zeros. This study compared the performance of four counting models used in mapping diseases: Poisson, negative binomial, zero-inflated Poisson, and zero-inflated negative binomial. The methods were compared in a simulation study. The models analyzed in the simulation were applied to a spatial ecological study of dengue data aggregated by census tracts in the city of Campinas, São Paulo State, Brazil, 2007. Spatial analysis was conducted with Bayesian hierarchical models. The zero-inflated Poisson model showed the best performance for estimating relative risk of dengue incidence in the census tracts.

Resumen: La incidencia de dengue se produce, predominantemente, en las áreas urbanas de las ciudades. Identificar el patrón de distribución espacial de la enfermedad a nivel local contribuye a la formulación de estrategias de control y prevención de la enfermedad. El análisis espacial de datos de conteo para pequeñas áreas comúnmente transgrede las suposiciones de los modelos tradicionales de Poisson, debido a la cantidad excesiva de ceros. En este estudio, se comparó el desempeño de cuatro modelos de conteo utilizados en el mapeo de enfermedades: Poisson, binomial negativo, Poisson con exceso de ceros y binomial negativo con exceso de ceros. Los métodos fueron comparados en un estudio de simulación. Los modelos analizados en el estudio de simulación fueron aplicados en un estudio ecológico espacial, a los datos de dengue agregados por sectores censales, del Municipio de Campinas, São Paulo, Brasil, 2007. El análisis espacial fue realizado con modelos jerárquicos bayesianos. El modelo de Poisson con exceso de ceros presentó un mejor desempeño para estimar el riesgo relativo de incidencia de dengue en los sectores censales.

The Effect of Geographic Units of Analysis on Measuring Geographic Variation in Medical Services Utilization / 예방의학회지

OBJECTIVES: We aimed to evaluate the effect of geographic units of analysis on measuring geographic variation in medical services utilization. For this purpose, we compared geographic variations in the rates of eight major procedures in administrative units (districts) and new areal units organized based on the actual health care use of the population in Korea. METHODS: To compare geographic variation in geographic units of analysis, we calculated the age-sex standardized rates of eight major procedures (coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, surgery after hip fracture, knee-replacement surgery, caesarean section, hysterectomy, computed tomography scan, and magnetic resonance imaging scan) from the National Health Insurance database in Korea for the 2013 period. Using the coefficient of variation, the extremal quotient, and the systematic component of variation, we measured geographic variation for these eight procedures in districts and new areal units. RESULTS: Compared with districts, new areal units showed a reduction in geographic variation. Extremal quotients and inter-decile ratios for the eight procedures were lower in new areal units. While the coefficient of variation was lower for most procedures in new areal units, the pattern of change of the systematic component of variation between districts and new areal units differed among procedures. CONCLUSIONS: Geographic variation in medical service utilization could vary according to the geographic unit of analysis. To determine how geographic characteristics such as population size and number of geographic units affect geographic variation, further studies are needed.

Mortalidade infantil nos municípios brasileiros: uma proposta de método de estimação / Infant mortality rate in Brazilian municipalities: a proposal of an estimation method

Propor um método para estimação do Coeficiente de Mortalidade Infantil (CMI) por município, levando em consideração a subenumeração de óbitos e a estimação do CMI em áreas de pequeno porte populacional. Métodos: o método foi desenvolvido a partir da estimação de fatores de correção de óbitos e nascidos vivos por município, no triênio 2009-2011, através de indicadores construídos para caracterizar a cobertura das informações vitais. Foi proposto um procedimento para verificar se o número corrigido de óbitos infantis atingiu o valor mínimo esperado de acordo com o porte populacional do município. No caso de insuficiência do fator de correção, foram usados os valores preditos de uma regressão multivariada para estimar o CMI. Resultados: os modelos de estimação dos fatores de correção das estatísticas vitais mostraram correlações inversas e significativas com os indicadores que caracterizam a cobertura dos dados vitais. Os valores preditos dos fatores de correção foram aplicados para todos os municípios localizados nos estados que não têm informações vitais completas. Em apenas 230 municípios, a correção foi considerada insuficiente. Conclusões: os achados evidenciam que existem, ainda, grandes problemas a superar, como as persistentes desigualdades relacionadas ao desenvolvimento socioeconómico, o acesso à assistência de saúde e à omissão da informação de óbito, que compromete o dimensionamento da situação local...

To propose a method to estimate the Infant Mortality Rate (IMR) by municipality, taking into consideration the underreporting of deaths and the IMR estimation in small population areas Methods: the method was developed on the basis of estimating the correction factors of death and live births by municipality, in the triennium 2009-2011, through indicators that characterize the completeness of vital information. A procedure to test if the corrected number of infant death achieved the expected minimum value was proposed accordingly to the municipality population size. In the case the correction is insufficient the predicted values of a multivariate regression were used to estimate the IMR. Results: the estimation models of the vital information correction factors showed inverse and significant correlations with the completeness indicators. The predicted correction factors were applied to all municipalities located in the states with incomplete vital information. In only 230 municipalities, the correction factors were considered not sufficient. Conclusion: the findings evidence that there are still great problems to surpass, such as the persistent inequalities related to socioeconomic development, access to health care, and omission of death reporting, which compromises the comprehension of a local situation...

Comparison of small area techniques for estimating prevalence of mental disorder symptoms among Iranian's southern adolescents

Mental disorders may lead to several complications in adolescents' people whose compensation is very difficult and sometime impossible. They are prone to emotional problems. Therefore, knowing prevalence of diseases and valid statistical technique is necessary to plan for prevention and control of diseases. In this cross-sectional study; direct, synthetic, and post-stratified estimation as small area methods were used to compute mental disorder symptoms [MDS] prevalence with county-level reference among adolescents in south of Iran. We conducted Mental Health Study data [MHS] conducted in Bushehr Province, southern Iran in 2005 for individual-level classification of MDS [n=2584]. Students were in grade 9, 10 and 11, and enrolled with complete satisfaction. The synthetic method was superior to the direct and post-stratified technique with respect to discrepancy statistics such as MSE and width 95% confidence interval [MSEs[synthetic]=0.001, MSEs[post-stratified]=0.010, MSEs[direct]=0.100]. In addition, the width range of 95% confidence intervals for all county estimates was 9.7% to 65.3% based on in direct methods. Besides, the width range of 95% confidence intervals for all county estimates under post-stratified and synthetic method was 16.7% to 62.2% and 11.8%-25.1%, respectively. Hence, we could categorize prevalence of mental disorder symptoms in Bushehr's counties into five categories based-on synthetic methods. Maximum and minimum prevalence belongs to Geneveh [0.403] and Dashty [0.398] counties, respectively. The MHS cannot be used as a valid source of county-level mental health prevalence data and the small-area method such synthetic method should be used to estimate prevalence of mental disorder symptoms in county-level. Furthermore, the synthetic method improved MDS prevalence more than direct and post-stratified methods

Small area variation in diabetes prevalence in Puerto Rico / Variación en un área pequeña de la prevalencia de la diabetes en Puerto Rico

OBJECTIVE: To estimate the 2009 prevalence of diagnosed diabetes in Puerto Rico among adults > 20 years of age in order to gain a better understanding of its geographic distribution so that policymakers can more efficiently target prevention and control programs. METHODS: A Bayesian multilevel model was fitted to the combined 2008-2010 Behavioral Risk Factor Surveillance System and 2009 United States Census data to estimate diabetes prevalence for each of the 78 municipios (counties) in Puerto Rico. RESULTS: The mean unadjusted estimate for all counties was 14.3% (range by county, 9.9%-18.0%). The average width of the confidence intervals was 6.2%. Adjusted and unadjusted estimates differed little. CONCLUSIONS: These 78 county estimates are higher on average and showed less variability (i.e., had a smaller range) than the previously published estimates of the 2008 diabetes prevalence for all United States counties (mean, 9.9%; range, 3.0%-18.2%).

OBJETIVO: Calcular la prevalencia en el año 2009 de casos con diagnóstico de diabetes en Puerto Rico en adultos de 20 años de edad o mayores, para conocer mejor su distribución geográfica con objeto de que los responsables políticos puedan encauzar más eficientemente los programas de prevención y control. MÉTODOS: Se ajustó un modelo multinivel bayesiano a la combinación de datos del Sistema de Vigilancia de Factores de Riesgo del Comportamiento 2008-2010 y del Censo de los Estados Unidos del 2009 para calcular la prevalencia de la diabetes en cada uno de los 78 municipios de Puerto Rico. RESULTADOS: El cálculo del valor medio no ajustado para todos los municipios fue de 14,3% (intervalo por municipio de 9,9 a 18,0%). La amplitud promedio de los intervalos de confianza fue de 6,2%. Hubo poca diferencia entre los cálculos ajustados y los no ajustados. CONCLUSIONES: Los valores obtenidos mediante estos cálculos correspondientes a 78 municipios fueron por término medio más elevados y mostraron menor variabilidad (es decir, el intervalo era más pequeño) que los cálculos anteriormente publicados sobre la prevalencia de la diabetes en todos los municipios de los Estados Unidos en el 2008 (media, 9,9%; intervalo de 3,0 a 18,2%).

Assessment of Applicability of Standardized Rates for Health State Comparison Among Areas: 2008 Community Health Survey / 예방의학회지

OBJECTIVES: This study shows the issues that should be considered when applying standardized rates using Community Health Survey(CHS) data. METHODS: We analyzed 2008 CHS data. In order to obtain the reliability of standardized rates, we calculated z-score and rank correlation coefficients between direct standardized rate and indirect standardized rate for 31 major indices. Especially, we assessed the change of correlations according to population composition (age and sex), and characteristics of the index. We used Mantel-Haenszel chi-square to quantify the difference of population composition. RESULTS: Among 31 major indices, 29 indices' z-score and rank correlation coefficients were over 0.9. However, regions with larger differences in population composition showed lower reliability. Low reliability was also observed for the indices specific to subgroups with small denominator such as 'permanent lesion from stroke', and the index with large regional variations in age-related differences such as 'obtaining health examinations'. CONCLUSIONS: Standardized rates may have low reliability, if comparison is made between areas with extremely large differences in population composition, or for indicies with large regional variations in age-related differences. Therefore, the special features of standardized rates should be considered when health state are compared among areas.

Análise espacial da Hanseníase na microrregião de Almenara, MG, Brasil / Análisis espacial de la Lepra en la microregión de Almenara, MG, Brasil / Spacial analysis of Leprosy in the microregion of Almenara, MG, Brazil

A hanseníase ainda é considerada um problema de saúde pública no Brasil. O objetivo deste estudo é analisar a situação epidemiológica da hanseníase na microrregião de Almenara/MG segundo sua distribuição espacial e suas relações com as condições socioeconômicas da população. Trata-se de um estudo ecológico. Os resultados colocam a microrregião como uma área hiperendêmica e indicam que os serviços de saúde não estão sendo capazes de detectar todos os casos existentes, contribuindo para manter a cadeia de transmissão da doença. A análise espacial identificou dois clusters, sendo um com coeficientes de detecção acima e outro abaixo do esperado. Acredita-se que os resultados obtidos servirão para balizar a elaboração e implementação de medidas de prevenção e controle da hanseníase na região.

Hansen's disease is still considered a public health problem in Brazil. The objective of this ecological study is to analyze the epidemiological status of Hansen's disease in the microregion of Almenara, State of Minas Gerais, according to its spatial distribution and its relations with the socioeconomic conditions of the population. The results of this study classify the microregion as a hyperendemic area and indicate that the health services are not capable of detecting all existing cases, thus contributing to the maintenance of the disease transmission chain. The spatial analysis identified two clusters, one with detection coefficients above and the other below those expected. It is believed that the results of the study will help to establish guidelines for the development and implementation of prevention and control measures for Hansen's disease in the region.

En Brasil, la hanseniasis todavía sigue siendo un problema de salud pública. El presente estudio ecológico tiene por objeto analizar la situación epidemiológica de la Hanseniasis en la microregión de Almenara, Estado de Minas Gerais, según su distribución espacial y su relación con las condiciones socioeconómicas de la población. Los resultados sitúan a la microregión en calidad de área híper endémica e indican que como los servicios de salud no logran detectar todos los casos existentes persiste la cadena de transmisión de la enfermedad. El análisis espacial identificó dos clusters: uno con coeficientes de detección por arriba y otro por debajo de lo esperado. Los resultados obtenidos podrán servir de base para elaborar y poner en práctica medidas de prevención y control de la hanseniasis en la región.

Comparisons of Health Inequalities in Small Areas with Using the Standardized Mortality Ratios in Korea / 예방의학회지

OBJECTIVES: This study was performed to compare the standardized mortality ratios among different small areas and to explore the usefulness of standardized mortality ratios in South Korea. METHODS: To calculate the standardized mortality ratio (SMR), we obtained the national deaths certificate data (2004-2006) and national registration population data (2003-2006), and these were provided by the National Statistical Office. The small areas (Eup.Myoun.Dong) were based on the subdivisions of counties. Among the 3,580 small areas classified by the National Statistical Office, 3,571 areas were included in this study. The basic statistics and decile distributions of the SMRs for all the regional levels were calculated, and the small area maps were also produced for some selected regions. To evaluate the precision of SMR, we calculated the 95% confidence intervals of the SMR in selected small areas. RESULTS: The mean and the standard deviation of the SMRs among all small areas were 100.8 and 17.0, respectively. The range was 30.6-211.7 and the inter-quartile range was 20.7. Seoul metropolitan city displayed the lowest mean SMR among 16 regions in South Korea, and 34.6 percent of the small area SMRs belonged to the first decile(the lowest group). On the contrary, the mean SMR of Gyeongsangnam province was highest, and 26.1 percent of the small area SMRs belonged to the tenth decile(the highest group). In some areas, the precision of the SMR, which was calculated by the 95% confidence intervals, remained questionable, yet it was quite stable for almost areas. CONCLUSIONS: The standardized mortality ratios can be useful for allocating health resources at the small area level in Korea.

Environmental Health Surveillance of Low Birth Weight in Seoul using Air Monitoring and Birth Data / 예방의학회지

OBJECTIVES: The principal objective of this study was to determine the relationship between maternal exposure to air pollution and low birth weight and to propose a possible environmental health surveillance system for low birth weight. METHODS: We acquired air monitoring data for Seoul from the Ministry of Environment, the meteorological data from the Korean Meteorological Administration, the exposure assessments from the National Institute of Environmental Research, and the birth data from the Korean National Statistical Office between January 1, 2002 and December 31, 2003. The final birth data were limited to singletons within 37~44 weeks of gestational age. We defined the Low Birth Weight (LBW) group as infants with birth weights of less than 2500g and calculated the annual LBW rate by district. The air monitoring data were measured for CO, SO2, NO2, and PM10 concentrations at 27 monitoring stations in Seoul. We utilized two models to evaluate the effects of air pollution on low birth weight: the first was the relationship between the annual concentration of air pollution and low birth weight (LBW) by individual and district, and the second involved a GIS exposure model constructed by Arc View 3.1. RESULTS: LBW risk (by Gu, or district) was significantly increased to 1.113(95% CI=1.111~1.116) for CO, 1.004 (95% CI=1.003~1.005) for NO2, 1.202(95% CI=1.199~ 1.206) for SO2, and 1.077(95% CI=1.075~1.078) for PM10 with each interquartile range change. Personal LBW risk was significantly increased to 1.081(95% CI=1.002~1.166) for CO, 1.145(95% CI=1.036~1.267) for SO2, and 1.053(95% CI=1.002~1.108) for PM10 with each interquartile range change. Personal LBW risk was increased to 1.003(95% CI=0.954~1.055) for NO2, but this was not statistically significant. The air pollution concentrations predicted by GIS positively correlated with the numbers of low birth weights, particularly in highly polluted regions. CONCLUSIONS: Environmental health surveillance is a systemic, ongoing collection effort including the analysis of data correlated with environmentally-associated diseases and exposures. In addition, environmental health surveillance allows for a timely dissemination of information to those who require that information in order to take effective action. GIS modeling is crucially important for this purpose, and thus we attempted to develop a GIS-based environmental surveillance system for low birth weight.

Application of GIS to the characterization of filariasis transmission in Narathiwat Province.

The geographical information system (GIS) and available survey data (both from the Filariasis Annual Reports, 1985-1999 and from the published literature) for the microfilarial infection rates are used to develop the first subdistrict-level endemicity maps of lymphatic filariasis in Narathiwat Province. The maps demonstrated the subdistrict-level geographical distribution of filariasis and the subdistricts at varied degrees of infection rate. The maps also indicate that, since 1985, there was a marked decrease in endemicity at the subdistrict level and in some areas, the infection rates were zero. However, transmission remained in the subdistricts surrounding peat swamp forest (Su-ngai Padi, Paluru, Puyo, Pasemat, Bang Khunthong, and Phron subdistricts). The house locations of infected cases, as well as the vector breeding places were geo-registered and placed as symbolic dots on the base maps obtained from Landsat's Thematic Mapper (TM) 5 and the land use map of Narathiwat to display the distribution of filariasis foci. Of 102 houses mapped, there were 40 houses in primary peat swamp forest (39.22%), 26 in rice fields (25.49%), 15 in fruit orchards (14.70%), 10 in coconut fields (9.80%) and others (10.78%). All the houses were close to the larval habitats presented in the survey. A 2-km buffer zone around the conservation boundary of primary peat swamp forest was created to locate risk areas of filariasis transmission. The buffer zone covered an area of 544.11 km2 and included 88.89% of the houses of infected cases found in 2002. It was able to identify 54 villages located in the buffer area, which might help in the determination of resource needs and resource allocation for filariasis control in Narathiwat Province.

Distribution of two species of malaria, Plasmodium falciparum and Plasmodium vivax, on Lombok Island, Indonesia.

Medical and entomological surveys were conducted to determine the risk factors of Plasmodium falciparum and P. vivax infections on Lombok Island, Indonesia, to find the risk factors and the main mosquito vectors for each malaria. Multivariate longitudinal analysis demonstrated two significant risk factors for infection with P. falciparum: disappearance of P. vivax parasitemia (p<0.001) and a specific study site (p<0.001). In contrast, younger age (p=0.024) and the interpolated virtual density of An. subpictus (p=0.041) were significantly associated with increased risk of infection with P. vivax. Thus, it seems that the distribution of P. vivax was determined largely by the presence of An. subpictus, whilst that of P. falciparum was influenced by antagonism with P. vivax. This result shows the importance of following-up treated P. vivax patients to identify recrudescence of P. falciparum in this area.

Leptospirosis disease burden estimation and surveillance networking in India.

Although leptospirosis is known to have occurred in India since the early years of the 20th century, no accurate data on disease burden exist. During the past two decades, leptospirosis cases have been reported with increasing frequency from different parts of the country. Several large outbreaks have occurred. In the year 2000, the Indian Council of Medical Research set up a Task Force on Leptospirosis. The Task Force conducted a multicentric study on disease burden due to leptospirosis. As part of the study, 3,682 patients with acute febrile illness, from 13 different centers in India, were investigated for the presence of current leptospiral infection using the Lepto-dipstick test. Of these patients, 469 (12.7%) were found to have leptospiral infection. The positivity rate ranged from 3.27% in the central zone to 28.16% in the southern zone. Fever, body aches and chills were the common symptoms observed. Urinary abnormalities, such as oliguria, yellow discoloration of urine and hematuria were found in 20%-40% of patients. Distribution of serogroups was studied based on microscopic agglutination test (MAT) titers. The southern zone had all the eleven serogroups in the panel, the eastern zone had nine, the northern zone eight, and the central and western zones had five circulating serogroups each. Among various risk factors studied, rat infestation of houses had the strongest association with leptospiral infection. Many other factors related to the environment, personal and occupational habits, etc, also had significant associations. The study had a few drawbacks. The Task Force has decided to continue the study with modified protocols to generate more accurate and detailed information about disease burden.

Aflatoxin contamination of food and food products in Thailand: an overview.

This paper presents an overview of reports of aflatoxin contamination in various foods and products, which have been carried out in Thailand between 1967-2001. Thirteen available international and local reports (n=3,206 samples) focused on type of food, season and geographic areas, and have been collected for statistical analysis. The accumulated data showed 1,248 (38.9%) of 3,206 samples were highly contaminated with aflatoxin. Over half (728) of the contaminated samples (1,248) were peanuts, milk, and poultry. In addition, analysis of the number of aflatoxin-contaminated samples in the above categaries, which were tested by chi-square test, indicated that there was a significant difference between the type of food and seasonal influence (p<0.05), but not geographical influence (p>0.05). Furthermore, detection methods for aflatoxin contamination, based on fundamental techniques, have been also reviewed. However, little research has been conducted on comparisons of the seasonal and geographical influences on aflatoxin contamination. Further study should be directed at these influences in larger samples.

Factors Determining Cesarean Section Frequency Rates of the OBGY Clinics in Metropolitan Area / 여성건강간호학회지

This study aims to find factors that affect variations in cesarean section frequency rates among OBGY clinics in Metropolitan areas. The factors include patient, medical supplier characteristics and economic factors. This study is a cross-sectional analysis using health insurance delivery claims from July to December 2000 and files of the NHIC(national health insurance corporation). Multiple regression was used to analyze the dependent variable of cesarean section frequency rate at each clinic. The results are as follows : Cesarean section frequency rate is increasing in proportion to the number of the following patients : repeated caesarean section, disproportion, obstructed labour, fetal distress, emergency caesarean section and self-employed patients. There are geographic variations as well. Cesarean section frequency rates are higher in Inchon and Gyonggi province than in Seoul. The higher number of total delivery the clinic has, the lower rate of cesarean section it has. Clinics with high frequency rates in 1999 showed higher rates the next year. Further research is required to develop evidence based delivery modes and change strategies for increasing normal delivery and activating midwife clinics.