Adverse perinatal outcomes for advanced maternal age: a cross-sectional study of Brazilian births / Resultados perinatais adversos em mulheres com idade materna avançada: estudo transversal com nascimentos brasileiros

ABSTRACT OBJECTIVES: To investigate the risk of adverse perinatal outcomes in women aged ≥41 years relatively to those aged 21-34. METHODS: Approximately 8.5 million records of singleton births in Brazilian hospitals in the period 2004-2009 were investigated. Odds ratios were estimated for preterm and post-term births, for low Apgar scores at 1 min and at 5 min, for asphyxia, for low birth weight, and for macrosomia. RESULTS: For pregnant women ≥41, increased risks were identified for preterm births, for post-term births (except for primiparous women with schooling ≥12 years), and for low birth weight. When comparing older vs. younger women, higher educational levels ensure similar risks of low Apgar score at 1 min (for primiparous mothers and term births), of low Apgar score at 5 min (for term births), of macrosomia (for non-primiparous women), and of asphyxia. CONCLUSION: As a rule, older mothers are at higher risk of adverse perinatal outcomes, which, however, may be mitigated or eliminated, depending on gestational age, parity, and, especially, on the education level of the pregnant woman.

RESUMO OBJETIVOS: Investigar o risco de resultados perinatais adversos em mulheres ≥ 41 anos relativamente àquelas com idade 21-34. MÉTODOS: Cerca de 8,5 milhões de registros de nascimentos únicos em hospitais brasileiros no período 2004-2009 foram investigados. Odds ratios foram estimados para nascimentos prematuros e pós-termo, baixos índices de Apgar no 1° e 5° minutos, asfixia, baixo peso ao nascer e macrossomia. RESULTADOS: Para as mulheres grávidas ≥ 41, aumento de riscos foram identificados para nascimentos prematuros, partos pós-termo (com exceção de primíparas com escolaridade ≥ 12 anos) e baixo peso ao nascer. Relativamente a mulheres mais velhas vs. mais jovens, maiores níveis de escolaridade garantem riscos semelhantes de baixo índice de Apgar no 1° minuto (para primíparas e nascimentos a termo), de baixo índice de Apgar no 5° minuto (para nascimentos a termo), de macrossomia (para não primíparas) e de asfixia. CONCLUSÃO: Em geral, mães mais velhas estão sob maiores riscos de desfechos perinatais adversos, mas esses são minimizados ou eliminados a depender da idade gestacional, da paridade e, em especial, da escolaridade da gestante.

Adverse perinatal outcomes for advanced maternal age: a cross-sectional study of Brazilian births.

OBJECTIVES: To investigate the risk of adverse perinatal outcomes in women aged ≥41 years relatively to those aged 21-34. METHODS: Approximately 8.5 million records of singleton births in Brazilian hospitals in the period 2004-2009 were investigated. Odds ratios were estimated for preterm and post-term births, for low Apgar scores at 1 min and at 5 min, for asphyxia, for low birth weight, and for macrosomia. RESULTS: For pregnant women ≥41, increased risks were identified for preterm births, for post-term births (except for primiparous women with schooling ≥12 years), and for low birth weight. When comparing older vs. younger women, higher educational levels ensure similar risks of low Apgar score at 1 min (for primiparous mothers and term births), of low Apgar score at 5 min (for term births), of macrosomia (for non-primiparous women), and of asphyxia. CONCLUSION: As a rule, older mothers are at higher risk of adverse perinatal outcomes, which, however, may be mitigated or eliminated, depending on gestational age, parity, and, especially, on the education level of the pregnant woman.

O papel da plausibilidade na avaliação da pesquisa científica / The role of plausibility in the evaluation of scientific research / El papel de la plausibilidad en la evaluación de la investigación científica

O artigo discute o impacto da plausibilidade (probabilidade a priori) no resultado de pesquisas científicas, conforme abordagem de Ioannidis, referente ao percentual de hipóteses nulas erroneamente classificadas como "positivas" (estatisticamente significante). A questão "qual fração de resultados positivos é verdadeiramente positiva?", equivalente ao valor preditivo positivo, depende da combinação de hipóteses falsas e positivas em determinada área. Por exemplo, sejam 90 por cento das hipóteses falsas e α = 0,05, poder = 0,8: para cada 1.000 hipóteses, 45 (900 x 0,05) serão falso-positivos e 80 (100 x 0,8) verdadeiro-positivos. Assim, a probabilidade de que um resultado positivo seja um falso-positivo é de 45/125. Adicionalmente, o relato de estudos negativos como se fossem positivos contribuiria para a inflação desses valores. Embora essa análise seja de difícil quantificação e provavelmente superestimada, ela tem duas implicações: i) a plausibilidade deve ser considerada na análise da conformidade ética de uma pesquisa e ii) mecanismos de registro de estudo e protocolo devem ser estimulados.

The paper discusses the impact of plausibility (the a priori probability) on the results of scientific research, according to the approach proposed by Ioannidis, concerning the percentage of null hypotheses erroneously classified as "positive" (statistically significant). The question "what fraction of positive results are true-positives?", which is equivalent to the positive predictive value, is dependent on the combination of true and false hypotheses within a given area. For example, consider an area in which 90 percent of hypotheses are false and α = 0.05 and power = 0.8: for every 1,000 hypotheses, 45 (900 x 0.05) are false-positives and 80 (100 x 0.8) are true-positives. Therefore, the probability of a positive result being a false-positive is 45/125. In addition, the reporting of negative results as if they were positive would contribute towards an increase in this fraction. Although this analysis is difficult to quantify, and these results are likely be overestimated, it has two implications: i) plausibility should be considered in the analysis of the ethical adequacy of a research proposal, and ii) mechanisms aimed at registering studies and protocols should be encouraged.

El artículo discute el impacto de la plausibilidad (probabilidad a priori) en el resultado de investigaciones científicas, conforme abordaje de Ioannidis, relacionado con el porcentaje de hipótesis nulas erróneamente clasificadas como "positivas" (estadísticamente significativas). La interrogante "cuál fracción de resultados positivos es verdaderamente positiva?", equivalente al valor predictivo positivo, depende de la combinación de hipótesis falsas y positivas en determinada área. Por ejemplo, sea el 90 por ciento de las hipótesis falsas y α= 0,05, poder= 0,8: para cada 1000 hipótesis, 45 (900 x 0,05) serán falsos positivos, y 80 (100 x 0,8) verdaderos positivos. Así, la probabilidad de que un resultado sea un falso positivo es de 45/125. Adicionalmente, el relato de estudios negativos como si fueran positivos contribuiría a la inflación de esos valores. A pesar de que el análisis sea de difícil cuantificación y probablemente super-estimado, el mismo tiene dos implicaciones: i) la plausibilidad debe ser considerada en el análisis de la conformidad ética de una investigación y ii) mecanismos de registro de estudio y protocolo deben ser estimulados.

The role of plausibility in the evaluation of scientific research.

The paper discusses the impact of plausibility (the a priori probability) on the results of scientific research, according to the approach proposed by Ioannidis, concerning the percentage of null hypotheses erroneously classified as "positive" (statistically significant). The question "what fraction of positive results are true-positives?", which is equivalent to the positive predictive value, is dependent on the combination of true and false hypotheses within a given area. For example, consider an area in which 90% of hypotheses are false and α = 0.05 and power = 0.8: for every 1,000 hypotheses, 45 (900 x 0.05) are false-positives and 80 (100 x 0.8) are true-positives. Therefore, the probability of a positive result being a false-positive is 45/125. In addition, the reporting of negative results as if they were positive would contribute towards an increase in this fraction. Although this analysis is difficult to quantify, and these results are likely be overestimated, it has two implications: i) plausibility should be considered in the analysis of the ethical adequacy of a research proposal, and ii) mechanisms aimed at registering studies and protocols should be encouraged.

Geographic accessibility to obstetric care and maternal mortality in a large metropolitan area of Brazil.

OBJECTIVE: To assess maternal mortality and its association with accessibility to obstetric care in the metropolitan region of Rio de Janeiro, Brazil. METHODS: Maternal mortality was assessed from 2 national databases, one administrative and the other designed for epidemiologic purposes. Distances traveled from residence to hospital via the transit network were calculated using a specialized information system. Deaths were grouped by area of residence, and maternal mortality ratios (number of deaths per 100,000 live births) as well as death incidence ratios (deaths/live births in 2 regions or hospital types) were calculated for these areas. RESULTS: We identified 236 deaths and estimated under-reporting at 30%. The most common causes of death were hypertension-related disorders, "other obstetric conditions," and complications from abortion; the longest traveled distance was 66.43 km (mean, 13.65 km); and maternal mortality ratios varied between 25.54% and 56.45%, the highest values being for areas with the lowest municipal human development index. The highest death incidence ratios were found at general hospitals without specialized obstetric care. CONCLUSION: Maternal mortality is still a serious problem in the studied region. The wide variations among areas of different socioeconomic conditions suggest the need for a better allocation of health care resources.

A cost simulation for mammography examinations taking into account equipment failures and resource utilization characteristics.

OBJECTIVE: This work develops a cost analysis estimation for a mammography clinic, taking into account resource utilization and equipment failure rates. MATERIALS AND METHODS: Two standard clinic models were simulated, the first with one mammography equipment, two technicians and one doctor, and the second (based on an actually functioning clinic) with two equipments, three technicians and one doctor. Cost data and model parameters were obtained by direct measurements, literature reviews and other hospital data. A discrete-event simulation model was developed, in order to estimate the unit cost (total costs/number of examinations in a defined period) of mammography examinations at those clinics. The cost analysis considered simulated changes in resource utilization rates and in examination failure probabilities (failures on the image acquisition system). In addition, a sensitivity analysis was performed, taking into account changes in the probabilities of equipment failure types. RESULTS: For the two clinic configurations, the estimated mammography unit costs were, respectively, US$ 41.31 and US$ 53.46 in the absence of examination failures. As the examination failures increased up to 10% of total examinations, unit costs approached US$ 54.53 and US$ 53.95, respectively. The sensitivity analysis showed that type 3 (the most serious) failure increases had a very large impact on the patient attendance, up to the point of actually making attendance unfeasible. CONCLUSIONS: Discrete-event simulation allowed for the definition of the more efficient clinic, contingent on the expected prevalence of resource utilization and equipment failures.

Optimizing patient flow in a large hospital surgical centre by means of discrete-event computer simulation models.

OBJECTIVE: This study used the discrete-events computer simulation methodology to model a large hospital surgical centre (SC), in order to analyse the impact of increases in the number of post-anaesthetic beds (PABs), of changes in surgical room scheduling strategies and of increases in surgery numbers. METHODS: The used inputs were: number of surgeries per day, type of surgical room scheduling, anaesthesia and surgery duration, surgical teams' specialty and number of PABs, and the main outputs were: number of surgeries per day, surgical rooms' use rate and blocking rate, surgical teams' use rate, patients' blocking rate, surgery delays (minutes) and the occurrence of postponed surgeries. Two basic strategies were implemented: in the first strategy, the number of PABs was increased under two assumptions: (a) following the scheduling plan actually used by the hospital (the 'rigid' scheduling - surgical rooms were previously assigned and assignments could not be changed) and (b) following a 'flexible' scheduling (surgical rooms, when available, could be freely used by any surgical team). In the second, the same analysis was performed, increasing the number of patients (up to the system 'feasible maximum') but fixing the number of PABs, in order to evaluate the impact of the number of patients over surgery delays. CONCLUSION: It was observed that the introduction of a flexible scheduling/increase in PABs would lead to a significant improvement in the SC productivity.

Análise Envoltória de Dados na avaliação de hospitais públicos nas capitais brasileiras / Data envelopment analysis for evaluating public hospitals in Brazilian state capitals

OBJETIVO: Aplicar a metodologia de Análise Envoltória de Dados na avaliação do desempenho de hospitais públicos em termos das internações em suas clínicas médicas. MÉTODOS: A eficiência dos hospitais foi medida a partir do desempenho de unidades de decisão nas variáveis estudadas para cada hospital, no ano 2000. Foram analisados dados referentes às internações em clínica médica dos hospitais SUS das capitais estaduais do Brasil e Distrito Federal (taxas de mortalidade e tempo médio de internação, valor médio da internação e perfil de doenças). A técnica de análise de correlação canônica foi introduzida na restrição do intervalo de variação das variáveis. O modelo Constant Returns to Scale foi utilizado para gerar escores que permitissem avaliar a eficiência das unidades. A partir dos escores obtidos, os municípios foram classificados de acordo com seu desempenho relativo nas variáveis analisadas. Procurou-se correlação entre os escores de classificação com variáveis exógenas: despesas com programas de saúde básica por habitante e índice de desenvolvimento humano das capitais. RESULTADOS: Nos hospitais estudados se destacaram as doenças do aparelho circulatório (23,6 por cento das internações); e a taxa de mortalidade foi de 10,3 por cento das internações. Das 27 capitais, quatro alcançaram 100 por cento de eficiência (Palmas, Macapá, Teresina e Goiânia), sete ficaram entre 85 por cento e 100 por cento, dez entre 70 por cento e 85 por cento e dez com menos de 70 por cento. CONCLUSÕES: A ferramenta utilizada mostrou ser aplicável para a avaliação de desempenho de hospitais públicos, revelando a grande variabilidade entre as capitais brasileiras, no que se refere às internações em clínica médica.

OBJECTIVE: To apply the Data Envelopment Analysis (DEA) methodology for evaluating the performance of public hospitals, in terms of clinical medical admissions. METHODS: The efficiency of the hospitals was measured according to the performance of decision-making units in relation to the variables studied for each hospital, in the year 2000. Data relating to clinical medical admissions in hospitals within the public system in Brazilian state capitals and Federal District (mortality rate, mean length of stay, mean cost of stay and disease profile) were analyzed. The canonical correlation analysis technique was introduced to restrict the variation range of the variables used. The constant returns to scale model was used to generate scores that would enable assessment of the efficiency of the units. From the scores obtained, these cities were classified according to their relative performance in the variables analyzed. It was sought to correlate between the classification scores and the exogenous variables of the expenditure on primary care programs per inhabitant and the human development index for each state capital. RESULTS: In the hospitals studied, circulatory diseases were the most prevalent (23.6 percent of admissions), and the mortality rate was 10.3 percent of admissions. Among the 27 state capitals, four reached 100 percent efficiency (Palmas, Macapá, Teresina and Goiânia), seven were between 85 and 100 percent, ten were between 70 and 85 percent and ten had efficiency of less than 70 percent. CONCLUSIONS: The tool utilized was shown to be applicable for evaluating the performance of public hospitals. It revealed large variations among the Brazilian state capitals in relation to clinical medical admissions.

[Data envelopment analysis for evaluating public hospitals in Brazilian state capitals]. / Análise Envoltória de Dados na avaliação de hospitais públicos nas capitais brasileiras.

OBJECTIVE: To apply the Data Envelopment Analysis (DEA) methodology for evaluating the performance of public hospitals, in terms of clinical medical admissions. METHODS: The efficiency of the hospitals was measured according to the performance of decision-making units in relation to the variables studied for each hospital, in the year 2000. Data relating to clinical medical admissions in hospitals within the public system in Brazilian state capitals and Federal District (mortality rate, mean length of stay, mean cost of stay and disease profile) were analyzed. The canonical correlation analysis technique was introduced to restrict the variation range of the variables used. The constant returns to scale model was used to generate scores that would enable assessment of the efficiency of the units. From the scores obtained, these cities were classified according to their relative performance in the variables analyzed. It was sought to correlate between the classification scores and the exogenous variables of the expenditure on primary care programs per inhabitant and the human development index for each state capital. RESULTS: In the hospitals studied, circulatory diseases were the most prevalent (23.6% of admissions), and the mortality rate was 10.3% of admissions. Among the 27 state capitals, four reached 100% efficiency (Palmas, Macapá, Teresina and Goiânia), seven were between 85 and 100%, ten were between 70 and 85% and ten had efficiency of less than 70%. CONCLUSIONS: The tool utilized was shown to be applicable for evaluating the performance of public hospitals. It revealed large variations among the Brazilian state capitals in relation to clinical medical admissions.

The association between socioeconomic indicators and cardiovascular disease risk factors in Rio de Janeiro, Brazil.

The objective of this study was to analyse the association between socioeconomic indicators and cardiovascular disease risk factors in adult residents of Rio de Janeiro city, Brazil. Data were obtained by direct interview and physical examination in a population-based cross-sectional study in the city of Rio de Janeiro, 1995-96. Subjects were selected by two-stage random sampling and information was collected on socioeconomic, anthropometric and demographic characteristics, as well as on existing risk factors for cardiovascular disease. An index to express the risk of cardiovascular disease (CVD) was built, based on the presence of two or more of the following risk factors: overweight (measured by the body mass index, BMI), fat location (measured by the waist-hip ratio index, WHR), smoking, hypertension, sedentary lifestyle and alcohol consumption. The association between this risk index and the socioeconomic variables level of schooling, per capita income and residence location (slum vs non-slum) was evaluated through logistic regression models that controlled for the age of the subjects. Two separate models were built, according to the gender of the subjects. Complete data were collected for 1413 males and 1866 females over the age of 20 years (82% of the intended sample). In the studied population, a considerable prevalence of risk for CVD was found: 42.2% among males and 65.4% among females. For males, the socioeconomic and demographic indicators retained in the logistic model were age (OR 1.01, 95% CI 1.00-1.01), level of schooling (1.77, 95% CI 1.39-2.26) and per capita income (OR 0.77, 95% CI 0.61-0.97). For females, the indicators retained were age (OR 1.02, 95% CI 1.01-1.02) and level of schooling (OR 2.26, 95% CI 1.84-2.77). The findings indicate that cardiovascular disease risk is already an alarming problem in the urban populations of developing countries, and that educational level is the most important socioeconomic factor associated with its presence.

Modelando a acessibilidade a serviços de saúde através de redes neurais artificiais / Modeling health services accessibility by means of artificial neural networks

Este artigo estuda a modelagem das distâncias percorridas por pacientes internados em unidades de saúde públicas no Município do Rio de Janeiro, através de RNAs e Regressäo Logística. As variáveis utilizadas como preditoras foram idade, leito, renda média do bairro de residência, e renda média dos bairros de localizaçäo dos hospitais; e a variável de saída as distâncias "reais" (considerando a malha viária). Foram analisados 8618 pacientes referentes ao capítulo do CID gravidez, parto e puerpério, obtidos de dados de Sistema de Informaçäo hospitalar (SIH-SUS), 1996. A partir do Código de Endereçamento Postal (CEP) da moradia do paciente, foi identificado o bairro e seu centróide e a Unidade de Saúde (destino), obtendo-se as coordenadas geográficas de destino e origem. Através delas foram calculadas as distâncias "reais" referentes aos deslocamentos dos pacientes. Os resultados indicaram serem as redes neurais capazes de, em 91 por cento dos casos, prever as distâncias percorridas pelos pacientes (dicotomizada como menor ou igual a 3km e maior que 3 km). Na regressäo logística esse valor foi 69,1 por cento. Na regressäo, apenas as variáveis leito e renda dos hospitais foram estatisticamente significativas (p=0,05). O método RNA apresentou resultados claramente superiores à regressäo logística, o que, possivelmente, explica-se devido às características näo lineares do problema.

Caracterizaçäo do uso de uma tecnologia diagnóstica de alto custo (tomografia computadorizada) em municípios do Estado do Rio de Janeiro / Characterization of the using of a diagnostical technology of high cost (computorized tomography) in county of the Rio de Janeiro state

Utilizando-se os bancos de dados de Autorização de Internação (BDAIH) e o Sistema de Informação Ambulatorial (BDSIA), recentemente disponibilizados pelo Ministério da Saúde (MS), este trabalho caracteriza o uso de uma tecnologia diagnóstica de alto custo (Tomógrafo Computadorizado), para Municípios do Rio de Janeiro, no período janeiro a outubro de 1995; relativamente à natureza dos hospitais e freqüência dos procedimentos médicos envolvidos. Os resultados apontam para uma deficiência na alocação da tecnologia, tanto em termos de sua distribuição geográfica quanto em relação aos hospitais que a oferecem.

With the help ofthe BDAIH (Hospital Admission Authorization Data Base)and BDSIA (Ambulatory Health System Data Base), recently made available by the Health Ministery, this work characterizes the use of a high cost diagnostic technology (Computerized Tomography), in Rio de Janeiro State, Brazil, January - October/95. The results show a skewed use ofthe technology, both in geographical and hospital provision terms.

Metodologia para estabilizaçäo de proporçöes de fatores de risco de saúde / Methodology for the stabilization of health rsk factors

O presente trabalho apresenta uma metodologia que permite a estabilizaçäo das proporçöes de fatores de risco de saúde. A seguir faz-se uma análise de como essa estabilizaçäo contribui à diferenciaçäo visual de áreas homogêneas de risco. Para fazer a comparaçäo visual dos resultados foi necessária a geraçäo de agrupamentos usando técnicas de análise multivariada, onde foram seguidos três passos. 1) estabilizaçäo de proporçöes de fatores de risco; 2) reduçäo do número de fatores de risco usando a Análise de Componetes Principais; 3) geraçäo de agrupamentos de casos usando a Análise de "Cluste".

Aplicaçäo de "path analysis" à modelagem de determinantes da mortalidade em menores de um ano / Application of the \"path analysis\" to modelling of mortality determination in under one year old

Neste trabalho utilizaram-se as técnicas de path analysis para descrever as interrelaçöes entre alguns determinantes da mortalidade em menores de um ano. Para estimar os coeficientes, efeitos indiretos e efeitos totais do modelo, utilizou-se o programa LISREL. Os resultados indicam que a área per capita de terra cultivada em cada município possui o maior efeito direto na mortalidade analisada, mesmo controlando-se os efeitos das variáveis de "renda" e "leitos". O maior efeito indireto é exercido pela variável de "alfabetizaçäo".

O SIG-APS: um sistema de informaçäo geográfica em atençäo primária em saúde / SIG-APS: geographic information system in primary health care

O presente trabalho apresenta o SIG-APS, uma ferramenta para apoio na tomada de decisões em nível de Sistemas Locais de Saúde, SILOS, no qual a análise estatística de dados é feita mediante a implementação de interfaces com aplicativos estatísticos convencionais. Como produto final é apresentada a distribuição espacial desses resultados. O SIG-APS foi desenvolvido para ser utilizado em ambiente Windows, para computadores pessoais constituindo-se assim em uma tecnologia de fácil acesso e baixo custo.