Risk assessment of nosocomial infection in patients with multiple myeloma in the first hospitalization / 公共卫生与预防医学

Objective To assess the risk of nosocomial infection in patients with multiple myeloma during their first hospitalization. Methods Totally 480 patients with multiple myeloma who were hospitalized for the first time in department of hematology of West China Hospital, Sichuan University from August 2021 to August 2022 were included, and the nosocomial infection during treatment was statistically analyzed. The patients were divided into infected group and uninfected group. The independent influencing factors of nosocomial infection were analyzed and a prediction model was established. The reliability of the prediction model was analyzed by receiver operating characteristic curve (ROC). Results The incidence rate of nosocomial infection was 31.2% among 480 patients hospitalized for the first time. There were statistically significant differences in age, ISS staging, controlling nutritional status (CONUT) score, agranulocytosis, hemoglobin, and albumin between the infected group and the uninfected group (P<0.05). Logistic multivariate regression analysis showed that age, ISS staging, CONUT score, agranulocytosis, hemoglobin level, and albumin level were all independent correlated factors of nosocomial infection in patients with multiple myeloma hospitalized for the first time (P<0.05). The area under the ROC curve (AUC), sensitivity and specificity of multivariate logistic regression prediction model were 0.88 (95%CI: 0.840-0.920), 85.00% and 76.36%, respectively. Conclusion The incidence rate of nosocomial infection is high among patients with multiple myeloma in the first hospitalization. The prediction model established according to independent correlated factors of nosocomial infection has high predictive value on the occurrence of nosocomial infection.

Is the Bland-Altman plot method useful without inferences for accuracy, precision, and agreement?

ABSTRACT OBJECTIVE This study aims to propose a comprehensive alternative to the Bland-Altman plot method, addressing its limitations and providing a statistical framework for evaluating the equivalences of measurement techniques. This involves introducing an innovative three-step approach for assessing accuracy, precision, and agreement between techniques, which enhances objectivity in equivalence assessment. Additionally, the development of an R package that is easy to use enables researchers to efficiently analyze and interpret technique equivalences. METHODS Inferential statistics support for equivalence between measurement techniques was proposed in three nested tests. These were based on structural regressions with the goal to assess the equivalence of structural means (accuracy), the equivalence of structural variances (precision), and concordance with the structural bisector line (agreement in measurements obtained from the same subject), using analytical methods and robust approach by bootstrapping. To promote better understanding, graphical outputs following Bland and Altman's principles were also implemented. RESULTS The performance of this method was shown and confronted by five data sets from previously published articles that used Bland and Altman's method. One case demonstrated strict equivalence, three cases showed partial equivalence, and one showed poor equivalence. The developed R package containing open codes and data are available for free and with installation instructions at Harvard Dataverse at https://doi.org/10.7910/DVN/AGJPZH. CONCLUSION Although easy to communicate, the widely cited and applied Bland and Altman plot method is often misinterpreted, since it lacks suitable inferential statistical support. Common alternatives, such as Pearson's correlation or ordinal least-square linear regression, also fail to locate the weakness of each measurement technique. It may be possible to test whether two techniques have full equivalence by preserving graphical communication, in accordance with Bland and Altman's principles, but also adding robust and suitable inferential statistics. Decomposing equivalence into three features (accuracy, precision, and agreement) helps to locate the sources of the problem when fixing a new technique.

Temporal trend in the incidence of tuberculosis-HIV coinfection in Brazil, by macro-region, Federative Unit, sex and age group, 2010-2021 / Tendencia temporal de la incidencia de coinfección tuberculosis-VIH en Brasil, por macrorregión, Unidad Federativa, sexo y grupo de edad, 2010-2021 / Tendência temporal da incidência de coinfecção tuberculose-HIV no Brasil, por macrorregião, Unidade da Federação, sexo e faixa etária, 2010-2021

ABSTRACT Objective To analyze the temporal trend in the incidence of tuberculosis-HIV coinfection in Brazil, by macro-region, Federative Unit, sex and age group, from 2010 to 2021. Methods: This was a time series study using surveillance data to estimate average annual percentage changes (AAPC), and 95% confidence intervals (95%CI) via joinpoint regression. Results: 122,211 cases of tuberculosis-HIV coinfection were analyzed; a falling trend was identified for Brazil as a whole (AAPC = -4.3; 95%CI -5.1;-3.7), and in the country's Southern (AAPC = -6.2; 95%CI -6.9;-5.5) and Southeast (AAPC = -4.6; 95%CI -5.6;-3.8) regions, even more so during the COVID-19 pandemic (2020-2021); the greatest falling trend was seen in Santa Catarina (AAPC = -9.3; 95%CI -10.1;-8.5), while the greatest rising trend was found in Tocantins (AAPC = 4.1; 95%CI 0.1;8.6); there was a rising trend among males, especially in Sergipe (AAPC = 3.9; 95%CI 0.4;7.9), and those aged 18 to 34 years, especially in Amapá (AAPC = 7.9; 95%CI 5.1;11.5). Conclusion The burden and trends of tuberculosis-HIV coinfection were geographically and demographically disparate.

RESUMEN Objetivo Analizar la tendencia temporal de la incidencia de la coinfección tuberculosis-VIH en Brasil, por Macrorregión, Unidad Federativa, sexo y grupo de edad, 2010-2021. Métodos Estudio de series de tiempo, con datos de vigilancia para la estimación de cambios porcentuales anuales promedio (CPAP) e intervalos de confianza del 95% (IC95%) vía joinpoint regression. Resultados Se analizaron 122.211 casos de coinfección tuberculosis-VIH; se identificó tendencia decreciente en Brasil (CPAP = -4,3; IC95% -5,1;-3,7) y en las regiones Sur (CPAP = -6,2; IC95% -6,9;-5,5) y Sudeste (CPAP = -4,6; IC95% -5,6;-3,8), aumentando durante la pandemia de covid-19; mayor tendencia decreciente ocurrió en Santa Catarina (CPAP = -9,3; IC95% -10,1;-8,5) y creciente en Tocantins (CPAP = 4,1; IC95% 0,1;8,6); hubo tendencia al aumento en el sexo masculino, especialmente Sergipe (CPAP = 3,9; IC95% 0,4;7,9), y en los de 18 a 34 años, especialmente Amapá (CPAP = 7,9; IC95% 5,1;11,5). Conclusión Había disparidades territoriales y demográficas en la carga y las tendencias de la coinfección tuberculosis-VIH.

RESUMO Objetivo Analisar a tendência temporal da incidência da coinfecção tuberculose-HIV no Brasil, por macrorregião, Unidade da Federação, sexo e faixa etária, 2010-2021. Métodos Estudo de séries temporais, com dados de vigilância, para a estimativa de variações percentuais anuais médias (VPAM) e intervalos de confiança de 95% (IC95%), por joinpoint regression. Resultados Foram analisados 122.211 casos de coinfecção tuberculose-HIV; identificou-se tendência decrescente no país (VPAM = -4,3; IC95% 5,1;-3,7) e em suas regiões Sul (VPAM = -6,2; IC95% -6,9;-5,5) e Sudeste (VPAM = -4,6; IC95% -5,6;-3,8), acentuada durante a pandemia de covid-19 (2020-2021); observou-se maior tendência decrescente em Santa Catarina (VPAM = -9,3; IC95% -10,1;-8,5) e maior tendência crescente no Tocantins (VPAM = 4,1; IC95% 0,1;8,6); houve tendência de incremento no sexo masculino, destacando-se Sergipe (VPAM = 3,9; IC95% 0,4;7,9), e na faixa etária de 18-34 anos, sobressaindo-se o Amapá (VPAM = 7,9; IC95% 5,1;11,5). Conclusão Verificaram-se disparidades territoriais e demográficas na carga e nas tendências da coinfecção tuberculose-HIV.

Factores asociados a dolor lumbar en trabajadores sanitarios de un hospital de referencia del Perú

Introducción: El dolor lumbar es una condición inevitable en todo el personal del rubro de la salud, con llevando desde malestar físico hasta una incapacidad funcional del individuo. Objetivo: Determinar los factores asociados a dolor lumbar entre los trabajadores sanitarios en un hospital de referencia del Perú. Metodología: El presente estudio es observacional, analítico, de corte transversal, temporalmente prospectivo, con muestreo no probabilístico. La población estuvo conformada por trabajadores sanitarios del Hospital Santa Rosa de Pueblo Libre durante el periodo de junio a diciembre del año 2022. Resultados: El análisis multivariado determinó que el ser hombre (OR: 2.818, p valor: 0.017), tener sobrepeso (OR:1.782, p valor: 0.013), demanda laboral alta (OR: 4.750, p valor: 0.026), realizar actividad física (OR: 3.610, p valor: 0.031) y tener antecedentes de trauma lumbar (OR: 2.423, p valor: 0.034), fueron factores estadísticamente significativos que se asociaron al dolor lumbar. Discusión: Se pudo observar que, los factores asociados a dolor lumbar fueron el sexo masculino, el sobrepeso, la demanda laboral alta, el realizar actividad física y el antecedente de trauma lumbar. Conocer estas variables permitirá realizar esquemas y charlas preventivas para afrontar esta recurrente patología.

Introduction: Low back pain is an unavoidable condition in all health personnel, ranging from physical discomfort to functional disability of the individual. Objective: To determine the factors associated with low back pain among health workers at a reference hospital in Peru. Methods: This study is observational, analytical, cross-sectional, temporally prospective, with non-probabilistic sampling. The population was made up of health workers from the Hospital Santa Rosa de Pueblo Libre during the period from June to December of the year 2022. Results: The multivariate analysis determined that being a man (OR: 2.818, p value: 0.017), being overweight (OR:1.782, p value: 0.013), high labor demand (OR: 4.750, p value: 0.026), performing physical (OR: 3.610, p value: 0.031) and having a history of low back trauma (OR: 2.423, p value: 0.034) were statistically significant factors associated with low back pain. Discussion: It was possible to observe that the factors associated with low back pain were the male sex, being overweight, high work demand, physical activity and a history of low back trauma. Knowing these variables will make it possible to carry out preventive schemes and talks to deal with this recurring pathology.

Fatores associados ao início precoce do aleitamento materno em crianças menores de 2 anos / Factors associated with early initiation of breastfeeding in children under 2 years of age / Factores asociados al inicio temprano de la lactancia materna en niños menores de 2 años

O aleitamento materno logo após o parto está associado à redução da mortalidade neonatal e infantil e à maior duração do aleitamento materno exclusivo. O objetivo deste estudo foi analisar os fatores associados ao início precoce do aleitamento materno em crianças menores de 2 anos de idade. Este estudo transversal foi conduzido durante a Campanha Nacional de Vacinação contra Poliomielite de 2012, em Guarapuava (PR), por meio de aplicação de questionário estruturado. Para identificação dos fatores, foram construídos modelos de regressão de Poisson, obtendo-se razões de prevalências em modelos bivariados e múltiplo. Mantiveram-se no modelo final as variáveis que apresentaram p < 0,05. A prevalência do aleitamento materno precoce foi de 78,54%, e os fatores associados ao não início do aleitamento materno precoce foram: criança do sexo masculino, baixo peso ao nascer, não nascer em hospital/maternidade e parto cesáreo. Idade materna entre 20 e 34 anos foi fator de proteção para o início precoce do aleitamento materno. É importante analisar os fatores de cada município para que, assim, sejam propostas ações efetivas direcionadas a serviços e profissionais de saúde e às mães.

Breastfeeding soon after delivery is associated with reduced neonatal and infant mortality and longer duration of exclusive breastfeeding. The aim of this study was to analyze the factors associated with early initiation of breastfeeding in children under 2 years of age. This cross-sectional study was conducted during the National Vaccination Campaign against Poliomyelitis of 2012, in Guarapuava (Paraná ­ PR), Brazil, by using a structured questionnaire. To identify the factors, Poisson regression models were constructed, obtaining prevalence ratios in bivariate and multiple models. The variables that presented p < 0.05 were maintained in the final model. The prevalence of early breastfeeding was 78.54%, and the factors associated with not starting early breastfeeding were: male children, low birth weight, not being born in a hospital/maternity, and cesarean delivery. Maternal age between 20 and 34 years was a protective factor for early initiation of breastfeeding. It is important to analyze the factors of each municipality so that effective actions are proposed for health services and professionals and for mothers.

La lactancia materna después del parto está asociada a una reducción de la mortalidad neonatal e infantil y a una mayor duración de la lactancia materna exclusiva. El objetivo de este estudio fue analizar los factores asociados al inicio temprano de la lactancia materna en niños menores de 2 años de edad. Este estudio transversal se realizó durante la Campaña Nacional de Vacunación contra la Poliomielitis de 2012, en Guarapuava, Paraná (Brasil), mediante la aplicación de un cuestionario estructurado. Para identificar los factores se construyeron modelos de regresión de Poisson, de los cuales se obtenieron razones de prevalencia en modelos bivariados y múltiple. Las variables que presentaron p < 0,05 permanecieron en el modelo final. La prevalencia de lactancia materna precoz fue del 78,54%, y los factores asociados a no iniciar la lactancia materna fueron los hijos varones, el bajo peso al nacer, no haber nacido en un hospital/maternidad y el parto por cesárea. La edad materna de entre 20-34 años fue un factor protector para el inicio temprano de la lactancia materna. Es importante analizar los factores de cada municipio para proponer acciones efectivas dirigidas a los servicios sanitarios y a los profesionales de la salud y las madres.

Willingness to Pay for Centralized Modern Locust Bean Processing Equipment in Ekiti State, Nigeria

This study investigated the propensity to pay for modern apparatus processing locust beans in Ekiti State, Nigeria. Utilizing primary data and a multistage sampling strategy, 240 processors were chosen for the study. The collected data were analyzed utilizing descriptive statistics and an inferential statistical instrument, such as Logit and ordinary least square regression analysis. About 72 percent of processors were married and had an average of eight years of experience processing locust legumes. The majority of respondents belonged to a cooperative group (66.7%) and had no access to credit (100%). The average monthly income from processing was N18,000. The majority of respondents (65%) were unwilling to pay for the service of centralized, advanced or contemporary processing equipment. According to the results of the Logit regression analysis, the variables that significantly influence willingness to pay for the service of centralized modern locust bean processing equipment were household income and processing experience (1%), level of education and age (5%), and household size (10%). The Ordinary Least Square (OLS) analysis reveals that household size and education level were significant at the 1% level, while age and marital status were significant at the 5% level and processing experience was significant at the 1% level. The study suggests that processors ready to pay should form a formidable cooperative to secure grants or loans to establish a centralized, contemporary locust processing cottage. The government should educate processors on modern food processing and safety at all levels.

Predictive models of newborn body composition: a systematic review / Modelos preditivos da composição corporal de neonatos: uma revisão sistemática

Abstract Objective: To analyze the prediction models of fat-free mass and fat mass of neonates who had air displacement plethysmography as a reference test. Data source: A systematic review of studies identified in the PubMed, Virtual Health Library (BVS), SciELO, and ScienceDirect databases was carried out. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist was used for inclusion of studies, the Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis (TRIPOD) report was used to select only predictive models studies, and the Prediction Model Risk of Bias Assessment Tool (PROBAST) was used to assess the risk of bias in the models. Data synthesis: This study is registered in PROSPERO with identification CRD42020175048. Five hundred and three studies were found during the searches, and only four papers (six models) were eligible. Most studies (three) used the sum of different skinfolds to predict neonatal body fat and all presented weight as the variable with the highest contribution to predicting neonatal body composition. Two models that used skinfolds showed high coefficients of determination and explained, significantly, 81% of the body fat measured by air displacement plethysmography, while the models using bioimpedance did not find a significant correlation between the impedance index and the fat-free mass. Conclusions: The few studies found on this topic had numerous methodological differences. However, the subscapular skinfold was a strong predictor of neonatal body fat in three studies. It is noteworthy that such model validation studies should be carried out in the future, allowing them to be subsequently applied to the population. The development of these models with low-cost tools will contribute to better nutritional monitoring of children and could prevent complications in adulthood.

RESUMO Objetivo Analisar os modelos de predição da massa livre de gordura e da massa de gordura de neonatos, tendo como teste de referência a pletismografia por deslocamento de ar. Fontes de dados Foi realizada uma revisão sistemática de estudos identificados nas bases de dados United States National Library of Medicine (PubMed), Biblioteca Virtual em Saúde, Scientific Electronic Library Online (SciELO) e ScienceDirect. O checklist Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) foi utilizado para a inclusão dos estudos, e o relatório Transparent Reporting of a multivariate prediction model for Individual Prognosis or Diagnosis (TRIPOD) foi utilizado para a seleção de apenas modelos preditivos. Para a avaliação de risco de viés dos modelos, foi empregada a ferramenta Prediction model study Risk of Bias Assessment Tool (PROBAST). Síntese dos dados O presente estudo encontra-se registrado no PROSPERO com identificação CRD42020175048. Durante as buscas foram encontrados 503 estudos, dos quais apenas quatro artigos (seis modelos) foram elegíveis. A maioria dos estudos (três) utilizou a soma de diferentes dobras cutâneas para predizer a gordura corporal neonatal, e todos apresentaram o peso como a variável com maior contribuição na predição da composição corporal do recém-nascido. Dois modelos que utilizaram dobras cutâneas mostraram altos coeficientes de determinação e explicaram, significantemente, 81% da gordura corporal aferida pela pletismografia por deslocamento de ar, enquanto os modelos que utilizaram a bioimpedância não encontraram correlação significante entre o índice de impedância e a massa livre de gordura. Conclusões Os poucos estudos encontrados sobre essa temática apresentaram inúmeras diferenças metodológicas. Todavia, observou-se em três trabalhos que a dobra cutânea subescapular é um forte preditor da gordura corporal neonatal. Destaca-se que, futuramente, devem ser realizados estudos de validação de tais modelos, permitindo que posteriormente eles sejam aplicados na população. Acredita-se que o desenvolvimento desses modelos, com ferramentas de baixo custo, trará contribuições para melhor acompanhamento nutricional infantil, podendo prevenir complicações na fase adulta.

Modelagem GAMLSS espaçotemporal da incidência de esquistossomose na região central do Estado de Minas Gerais, Brasil / Modelado espaciotemporal GAMLSS para la incidencia de esquistosomiasis en la región central del estado de Minas Gerais, Brasil / Spatio-temporal GAMLSS modeling of the incidence of schistosomiasis in the central region of the State of Minas Gerais, Brazil

Resumo: No Brasil, milhões de pessoas vivem em áreas de risco para a esquistossomose, uma doença negligenciada, de caráter crônico e com elevada morbidade. O helminto Schistosoma mansoni está presente em todas as macrorregiões, incluindo o Estado de Minas Gerais, um dos mais endêmicos. Por essa razão, a identificação de potenciais focos é fundamental para subsidiar políticas públicas de cunho educativo e profilático no controle desse desfecho. Nesse contexto, o objetivo do trabalho consiste em modelar dados de esquistossomose em relação aos aspectos espaciais e temporais, além de avaliar a importância de algumas variáveis exógenas socioeconômicas e a presença das principais espécies de Biomphalaria. Como trabalhar com casos incidentes, uma variável discreta de contagem, exige uma modelagem apropriada, foi escolhida a modelagem GAMLSS por considerar conjuntamente uma distribuição mais adequada à variável resposta devido à inflação de zeros e à heterocedasticidade espacial. Verificaram-se valores elevados de incidência em diversos municípios de 2010 a 2012 e uma tendência de queda até 2020. Também foi identificado que a distribuição da incidência se comporta de maneira diferente no espaço e no tempo. Municípios com barragem apresentaram risco 2,25 vezes maior do que os que não a continham. A presença de B. glabrata foi relacionada ao risco de ocorrência da doença. Por outro lado, a presença de B. straminea refletiu em menor risco de ocorrência da esquistossomose. Conclui-se que o controle e o acompanhamento dos caramujos da B. glabrata podem ser fundamentais para a contenção e a eliminação da esquistossomose e o modelo GAMLSS foi eficaz para tratamento e modelagem de dados espaçotemporais.

Resumen: En Brasil, millones de personas viven en áreas de riesgo de esquistosomiasis, una enfermedad crónica desatendida y con alta morbilidad. El helminto Schistosoma mansoni está presente en todas las macrorregiones, incluido el Estado de Minas Gerais, uno de los más endémicos del país. Por ello, la identificación de potenciales brotes es fundamental para promover políticas públicas de carácter educativo y profiláctico en el control de este desenlace. En este contexto, el objetivo de este trabajo es modelar datos sobre esquistosomiasis con respecto a aspectos espaciotemporales, además de evaluar la importancia de algunas variables socioeconómicas exógenas y la presencia de las principales especies de Biomphalaria. Dado que en el trabajo con casos incidentes una variable de conteo discreta requiere un adecuado modelado, se eligió el modelo GAMLSS, ya que en conjunto considera una distribución más adecuada para la variable de respuesta debido a la inflación de ceros y la heterocedasticidad espacial. Se encontraron valores de alta incidencia en varios municipios en el periodo evaluado de 2010 a 2012 y una tendencia a descenso hasta 2020. También se verificó que existe una distribución de incidencia de manera diferente en el espacio y el tiempo. Los municipios con represas presentaban 2,25 veces más riesgo que los que no las tenían. La presencia de B. glabrata estuvo relacionada con el riesgo de la enfermedad. Por otro lado, la presencia de B. straminea ocasionaba un menor riesgo de padecer la enfermedad. Se concluye que el control y seguimiento de caracoles B. glabrata puede ser fundamental para el control y eliminación de la esquistosomiasis y que el modelo GAMLSS resultó ser efectivo para el tratamiento y modelado de datos espaciotemporales.

Abstract: In Brazil, millions of people live in areas with risk of schistosomiasis, a neglected chronic disease with high morbidity. The Schistosoma mansoni helminth is present in all macroregions of Brazil, including the State of Minas Gerais, one of the most endemic states. For this reason, the identification of potential foci is essential to support educational and prophylactic public policies to control this disease. This study aims to model schistosomiasis data based on spatial and temporal aspects and assess the importance of some exogenous socioeconomic variables and the presence of the main Biomphalaria species. Considering that, when working with incident cases, a discrete count variable requires an appropriate modeling, the GAMLSS modeling was chosen since it jointly considers a more appropriate distribution for the response variable due to zero inflation and spatial heteroscedasticity. Several municipalities presented high incidence values from 2010 to 2012, and a downward trend was observed until 2020. We also noticed that the distribution of incidence behaves differently in space and time. Municipalities with dams presented risk 2.25 times higher than municipalities without dams. The presence of B. glabrata was associated with the risk of schistosomiasis. On the other hand, the presence of B. straminea represented a lower risk of the disease. Thus, the control and monitoring of B. glabrata snails is essential to control and eliminate schistosomiasis; and the GAMLSS model was effective in the treatment and modeling of spatio-temporal data.

Influência da Gordura do Braço sobre Medida Indireta da Pressão Sanguínea: Uma Abordagem Estatística e de Machine Learning / Influence of Arm Fat on the Indirect Measurement of Blood Pressure: A Statistical and Machine Learning Approach

Resumo Fundamento A mensuração indireta da pressão sanguínea (PS) é sabidamente influenciada por diversos fatores como técnica, observador e equipamento, mas a influência da composição do braço ainda não foi investigada. Objetivo Identificar a influência da gordura do braço sobre a medida indireta da pressão sanguínea, utilizando modelos de inferência estatística e machine learning. Métodos Estudo transversal, com 489 adultos jovens saudáveis de 18 a 29 anos de idade. Foram medidos comprimento (COB), circunferência do braço (CB) e índice de gordura do braço (IGB). A PS foi mensurada em ambos os braços, simultaneamente. Os dados foram processados utilizando-se Python 3.0 e pacotes específicos para análise descritiva, regressão e clusterização. Um nível de significância de 5% foi adotado para todos os cálculos. Resultados A PS e as medidas antropométricas foram diferentes entre os hemicorpos. A pressão sanguínea sistólica (PAS), COB, e IGB foram maiores no braço direito (BD), enquanto CB foi similar em comparação ao braço esquerdo. COB e CB apresentaram correlação positiva com a PAS. Conforme o modelo de regressão, para determinado valor de CB e COB, a leitura da PAS poderá ter uma redução média de 1,80 mmHg no BD, e 1,62 mmHg no braço esquerdo, a cada 10% de aumento na IGB. A clusterização corroborou os resultados da regressão. Conclusão Foi encontrada uma influência significativa do IGB sobre a leitura da PS. A PAS teve correlação positiva com COB e CB, e correlação negativa com IGB, o que sugere a necessidade de mais investigações sobre a relação da PS com as frações de gordura e músculo do braço.

Abstract Background The indirect measurement of blood pressure (BP) is known to be influenced by many factors such as the technique, observer, and equipment; however, the influence of arm composition has not been investigated yet. Objective To identify the influence of arm fat on the indirect measurement of blood pressure using statistical inference and machine learning models. Methods Cross-sectional study, with 489 healthy young adults aged from 18 to 29 years old. Measurements of arm length (AL), arm circumference (AC) and arm fat index (AFI) were taken. BP was measured in both arms simultaneously. Data were processed using Python 3.0 and its specific packages for descriptive analysis, regression and cluster analysis. Significance levels: 5% for all calculations. Results BP and anthropometric measurements were different between the hemi-bodies. In the right arm, systolic blood pressure (SBP), AL and AFI were higher, while AC was similar compared with the left arm. AL and AC showed positive correlation with SBP. According to the regression model, for a fixed value of AC and AL, SBP readings could be reduced by a mean of 1.80 mmHg in the right arm, and 1.62 mmHg in the left arm for every 10% increase in AFI. Clustering analysis corroborated the regression results. Conclusion There was a significant influence of AFI on BP readings. SBP had a positive correlation with AL and AC, and a negative correlation with AFI, suggesting the need for further investigations on the relationship between BP and percentages of arm muscle and fat.

Social inequalities in the temporal trend of mortality from sickle cell disease in Brazil, 1996-2019 / Desigualdades sociais na tendência temporal de mortalidade por doença falciforme no Brasil, 1996-2019 / Desigualdades sociales en la tendencia temporal de la mortalidad por enfermedad de células falciformes en Brasil, 1996-2019

Contrary to international trends, the mortality rate of sickle cell disease increased in Brazil after the implementation of the neonatal screening program, probably due to improving access to diagnosis. This study aimed to assess differences in the temporal trend of the mortality rate and median age at death from sickle cell disease in Brazil, considering implemented measures to expand diagnosis, and improve health care access in-country and in the international scenario. Time series were extracted from the Brazilian Mortality Information System from 1996 to 2019. Changes in the mortality rate and median age at death were verified via segmented regression models, which were stratified by sex, region of residence, and age. Most deaths occurred in non-white people, young adults, and the Southeast and Northeast population. Sickle cell disease mortality rate increased until 2010 (13.31%; 95%CI: 6.37; 20.70), particularly in individuals aged 30 years or more (12.78%; 95%CI: 2.98; 23.53) and in the Northeast (12.27%; 95%CI: 8.92; 15.72). Most deaths occurred in the second decade of life (3.01 deaths/million), with a 59% increase in the median age of death in Brazil, from 27.6 to 30.3 years, more pronounced in females and the North Region. The observed gain in the survival of sickle cell disease in Brazil is still much lower than in developed countries and presents regional disparities, probably due to the lack of access to health care and recent treatments, such as hydroxyurea, still restricted to hematological referral centers in Brazilian capitals.

Ao contrário dos estudos internacionais, houve um aumento da taxa de mortalidade por doença falciforme no Brasil após a implantação do programa de triagem neonatal, provavelmente devido à melhoria do acesso ao diagnóstico. O objetivo deste estudo foi avaliar as diferenças na tendência temporal da taxa de mortalidade por doença falciforme e idade mediana ao morrer no Brasil, considerando as medidas implementadas para ampliar o diagnóstico e melhorar o acesso à saúde no país e no cenário internacional. As séries temporais foram extraídas do Sistema de Informação sobre Mortalidade de 1996 a 2019. Mudanças na magnitude da taxa de mortalidade e na idade mediana ao morrer foram verificadas via modelos de regressão segmentada, estratificados por sexo, região de residência e idade. A maioria dos óbitos ocorreu entre jovens, pretos ou pardos, e habitantes das regiões Sudeste e Nordeste. Houve um aumento da taxa de mortalidade por doença falciforme até 2010 (13,31%; IC95%: 6,37; 20,70), especialmente em indivíduos com 30 anos ou mais (12,78%; IC95%: 2,98; 23,53) e habitantes do Nordeste (12,27%; IC95%: 8,92; 15,72). A maioria dos óbitos ocorreu durante a segunda década de vida (3,01 óbitos/milhão), com um aumento de 59% na idade mediana ao morrer no Brasil (de 27,6 para 30,3 anos), mais acentuada entre mulheres e na Região Norte. O aumento observado na sobrevivência da doença falciforme no Brasil ainda é muito menor do que em países desenvolvidos e com disparidades regionais, provavelmente pela falta de acesso aos serviços de saúde e aos tratamentos recentes, como a hidroxiureia, que ainda é restrita aos centros de referência hematológicos das capitais brasileiras.

A diferencia de los estudios internacionales, en Brasil se produjo un aumento de la tasa de mortalidad por enfermedad de células falciformes tras la implantación del programa de tamizaje neonatal, probablemente debido a la mejora del acceso al diagnóstico. El objetivo del estudio es determinar las diferencias en la tendencia temporal de la tasa de mortalidad y la edad media de muerte por enfermedad de células falciformes en Brasil, teniendo en cuenta las medidas implementadas para ampliar el diagnóstico y mejorar el acceso a la atención sanitaria en el país y en el escenario internacional. Las series temporales fueron extraídas del Sistema de Información sobre de Mortalidad de 1996 a 2019. Los cambios en la magnitud de la tasa de mortalidad y la edad media de la muerte se identificaron con modelos de regresión segmentados, estratificados por sexo, región de residencia y edad. La mayoría de las muertes ocurrieron en personas de color, adultos jóvenes y los habitantes del sureste y noreste. Hubo un aumento de la tasa de mortalidad por enfermedad de células falciformes hasta 2010 (13,31%; IC95%: 6,37; 20,70), sobre todo en individuos de 30 años o más (12,78%; IC95%: 2,98; 23,53) y en el Noreste (12,27%; IC95%: 8,92; 15,72). La mayoría de las muertes ocurrió en la segunda década de la vida (3,01 muertes/millón), con un aumento del 59% en la edad media de muerte en Brasil, de 27,6 a 30,3 años, más pronunciado en las mujeres y en el Norte. La ganancia observada en la supervivencia de la enfermedad de células falciformes en Brasil es todavía muy inferior a la de los países desarrollados y con disparidades regionales, probablemente debido a la falta de acceso a la asistencia sanitaria y a los tratamientos recientes, como la hidroxiurea, todavía restringidos a los centros de referencia hematológica de las capitales brasileñas.

A longitudinal study on association between puberty development and thyroid function of school aged girls in Minhang District, Shanghai / 中国学校卫生

Objective@#To observe the association between puberty development and thyroid function among school-aged girls in Minhang District of Shanghai, in order to explore the effect of puberty development on thyroid function. @*Methods@#The study was based on a cohort of adolescent girls recruited in iodine-suitable areas of Minhang District, and the baseline and follow-up survey have been carried out from January to March 2019. The method of phased cluster sampling was used to select one junior high school in the east, south, north and middle of Minhang District, Shanghai, respectively. Finally, 464 new junior high school girls were included in the Cohort study for physical examination, and girls were followed up from January to March 2021. The Puberty Development Scale (PDS) was used to assess the stage of puberty. Serum thyroid stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) were determined for each participant. Thyroid homeostasis structure parameters (THSPs) was calculated. Changes of Thyroid hormones at baseline and follow-up were compared by Wilcoxon signed rank sum test. Multiple linear regression analyses were used to evaluate the associations of thyroid hormones (THs) and THSPs changes with pubertal develepment.@*Results@#Serum TSH levels of female studentds decreased significantly, while their FT3 and FT4 levels increased significantly during the study period ( Z=-10.53, -4.71, -12.46, P <0.01). In multiple linear regression analysis after adjustment for co-variables (including baseline age, change of BMI and waist circumference), FT4 and thyroid feedback quantile-based index (TFQI) in the higher puberty category scores changes (△PCS) group were further reduced compared with those in the low △PCS group ( β =-0.66, -0.55 ). Compared to the late puberty at baseline and follow-up (BLFL) group, FT4 and TFQI showed higher decline in the pre-puberty at baseline and late puberty at follow-up (BPFL) group with the pre-puberty at baseline and end of puberty at follow-up (BPFT) group ( β =-0.55, -0.44)( P <0.05). There were no association of △TSH, △FT3, △FT4/FT3 and TSH index changes (△TSHI) with △PCS or the puberty pattern.@*Conclusion@#Serum TSH decreases while serum FT3 and FT4 increase among girls during puberty. Both the initial stage and the velocity of pubertal development are related to thyroid hormone fluctuations.

Association between non school sedentary time and myopia among primary and secondary school students with different levels of physical activity / 中国学校卫生

Objective@#To analyze the association between non-school sedentary time and myopia among primary and secondary school students with different levels of physical activity, so as to provide data for precise measures to prevent and control myopia.@*Methods@#From September to December 2019, stratified cluster sampling was used to select 7 872 primary and secondary students in grades 4 to 12, middle and high school students from Hefei, Suzhou, Chizhou and Wuhu Cities in Anhui Province. Face-to-face questionnaires and vision examinations were conducted to collect demographic information, physical activity time, sedentary study time and visual health status. Potential categories were analyzed for different types of physical activity time, and Logistic regression was used to assess the relationship between non-school sedentary time and myopia at different levels of physical activity.@*Results@#A total of 2 976 primary and secondary school students were found with high physical activity levels and 4 896 primary and secondary school students with low physical activity levels. The proportion of low physical activity was higher in girls than in boys (68.7% vs . 55.6%), and the differences were statistically significant ( χ 2=143.97, P <0.01). The overall screening myopia rate was 48.2%, with statistically significant differences among female students (53.0%) compared with male students (43.3%), urban students ( 51.8 %) compared with rural students (44.5%), and longer non-school sedentary time students (60.6%) compared with average (45.1%) and shorter (42.1%) non-school sedentary time students, and the differences were statistically significant ( χ 2=73.15, 41.96 , 161.74, P <0.01). Adjusting for confounders such as residence, grade, gender, age, father s education, mother s education, and body mass index (BMI), multivariate Logistic regression analysis revealed that prolonged after-school sedentary study was positivety correlated with myopia among primary and secondary school students of low physical activity levels ( OR=1.52, 95%CI=1.27-1.83, P <0.01), and there was no statistical association between after-school sedentary time and myopia in primary and secondary school students with high physical activity levels ( P >0.05).@*Conclusion@#Attention should be paid to non-school sedentary time for primary and secondary school students with low physical activity levels. And students who spend a lot of time sitting outside of school should be encouraged to maintain high physical activity levels to reduce the risk of myopia.

Association between depression and anxiety symptoms with physical activity among rural returning adolescents / 中国学校卫生

Objective@#To understand the symptoms of depression and anxiety among rural returning adolescents and to analyze their association with physical activity related factors, so as to provide reference for interventions targeting depression and anxiety symtoms in the population.@*Methods@#From April to June 2020, 3 495 middle school students were selected from 6 counties and districts of Shangrao City by random cluster stratified sampling sampling. The Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7) were used to evaluate the depressive and anxiety symptoms among middle school students. The International Physical Activity Questionnaire was used to assess their physical activity levels during the past week. Chi square test and Logistic regression analysis were used to determine the strength of the association between depression and anxiety symptoms and physical activity related factors in returning and non returning adolescents as well as the overall population.@*Results@#Univariate analysis showed significant differences in the prevalence of depressive and anxiety symptoms between rural returning and non returning adolescents and the overall population in terms of "type of school" "family economic situation" "parental occupation" "number of sports classes per week" and "level of physical activity per week" ( χ 2=78.21, 16.56, 135.44, 107.75, 7.10, 8.62; 97.94, 24.26 , 124.07, 90.36, 9.60, 8.34, P <0.05). Multivariate regression analysis showed a correlation between the occurrence of depression and the number of sports classes per week for rural returning and non returning adolescents and the overall population (number of sports classes per week for non returning was 2 times, OR=1.22, 95%CI =1.01-1.49; returning adolescents for 1 time, OR=1.85, 95%CI =1.06-3.23; the overall population for 1 time, OR=1.34, 95%CI =1.01-1.77 and 2 times, OR=1.20, 95%CI =1.01-1.43, P <0.05). There was a correlation between anxiety symptoms and the number of sports classes per week for returning adolescents (number of sports classes per week for returning adolescents was 1 time, OR=2.10, 95%CI=1.21-3.63, P < 0.05 ).@*Conclusion@#A low frequency of weekly sports classes may be a risk factor for depressive or anxiety symptoms in rural and returning adolescents. Rural primary and secondary schools should appropriately increase the number of physical education courses or arrange sports extended classes to promote the development of adolescent mental health.

Relationship between chronotype and mental health problems among middle school students in Taiyuan / 中国学校卫生

Objective@#To examine mental health problems among adolescents in Taiyuan City and its relationship to chronotype, so as to give a scientific basis for supporting mental health of middle school students.@*Methods@#From October to November 2021, a total of 2 621 pupils were enrolled from three junior high schools and two senior high schools in Taiyuan by using a multi stage stratified cluster random sampling method to investigate demographic characteristics, mental health status, and chronotype. Chi squared test, Spearman correlation analysis and Logistic regression were used to analyze the relationship between sleep patterns and mental health problems in middle school students.@*Results@#The proportion of morning, intermediate and evening types of middle school students sleep were 17.9%, 65.6%, and 16.4%, respectively. The overall detection rate of mental health problems was 13.8 %, which was statistically significant among middle school students in different grades, self perceived family economic status, the number of friends and sleep patterns ( χ 2=42.69, 29.15, 46.02, 93.99, P <0.05). After adjusting for grade, self perceived family economic status and the number of friends, Logistic regression analysis revealed that mental health problems were positively associated with evening type ( OR =2.84) and negatively associated with morning type ( OR =0.61)( P ＜0.05).@*Conclusion@#Chronotype is associated with mental health problems among middle school students, with a higher risk for evening type and a lower risk for morning type. Mental health of middle school students can be enhanced by changing their chronotype.

Association of vitamin D deficiency with anxiety and depressive symptoms among middle school students in Shenzhen / 中国学校卫生

Objective@#To explore the association of vitamin D deficiency with anxiety and depressive symptoms as well as their comorbidity, so as to provide references for improving the mental health of children and adolescents.@*Methods@#From October to December 2021, a total of 1 323 students from four middle schools in Shenzhen were selected by using convenience sampling method for a questionnaire survey and physical examination. Fasting blood samples were collected to detect vitamin D levels. The Chi square test and multiple Logistic regression model were used to analyze the association of vitamin D deficiency with anxiety and depressive symptoms and their comorbidity among middle school students.@*Results@#The detection rates of anxiety, depressive, and thier comorbidities in middle school students were 33.0%, 21.5% and 16.3%, respectively. After adjusting for confounding factors, vitamin D deficiency was positively associated with the risk of anxiety symptoms ( OR=1.59, 95%CI =1.02-2.46), depressive symptoms ( OR=1.94, 95%CI =1.22-3.09) and anxiety depressive comorbid symptoms ( OR=1.75, 95%CI =1.06-2.90) in secondary school students ( P ＜0.05).@*Conclusion@#Vitamin D deficiency is associated with an increased risk of anxiety, depressive and their co morbidity symptoms in middle school students, and the directionality of the association should be further studied.

Consistency and influencing factors in parents knowledge, attitude and practice about early childhood sex education in rural areas / 中国学校卫生

Objective@#To understand the consistency and factors influencing rural parents knowledge, attitude and practice about early childhood sex education, so as to put forward effective suggestions and countermeasures for improving childhood sex education in rural areas.@*Methods@#A multi stage stratified sampling method was used to investigate the knowledge, attitude and practice of early childhood sex education among 1 015 parents in 16 kindergartens in rural areas of Sichuan from March to May 2019. Chi square text and multivariate Logistic regression analysis were used to analyze factors affecting the consistency of parents knowledge, attitude and practice of childhood sex education.@*Results@#Nearly 64.9%, 85.9% and 44.7% of parents with sufficient knowledge, support, and implement of early children s sex education, respectively, and the consistency rate of knowledge, attitude and practice were 30.2%. The results of the multivariate Logistic regression analysis showed that parents aged <31 years ( OR= 5.35 , 95%CI =2.93-9.77), 31-40 years ( OR=4.82, 95%CI =2.65-8.76) and 41-50 years ( OR=2.37, 95%CI =1.10-5.11), and the mother s education level being middle school ( OR=3.67, 95%CI =1.75-7.69), secondary/high school ( OR=2.83, 95%CI =1.32-6.05) and college/bachelor s degree and above ( OR=5.44, 95%CI =2.23-12.98), sex related questions asked by child ( OR=2.00, 95%CI =1.44-2.78), having sex education in the family ( OR=5.38, 95% CI =3.82-7.59), believing that parents should be responsible for sex education for young children ( OR=2.58, 95%CI =1.40-4.74) had a higher consistency rate of knowledge, attitude and practice in early childhood sex education ( P <0.05).@*Conclusion@#In rural areas of Sichuan, although parents highly support early childhood sex education, the eligible rate of knowledge and the implementing rate are quite low, as well as the consistent rate of knowledge, attitude and practice. Relevant departments should pay attention to strengthen publicity and education, especially among older parents, low educated parents and those opposed to or not yet implementing child sex education.

Current status and influencing factors of oral healthrelated quality of life among senior primary school students in Bengbu / 中国学校卫生

Objective@#To investigate oral health related life quality and associated factors of senior primary school students in Bengbu City, so as to provide scientific basis for targeted oral health education for children.@*Methods@#A stratified cluster random sampling method was adopted to select 1 760 senior students (grade 5 to 6) from 12 primary schools in 4 districts of Bengbu City from September to November 2022. A cross sectional survey was conducted on the oral health of students through questionnaires related to oral health. The effect of oral problems on quality of life was assessed by the Child Daily Life Oral Influence Scale (Child-OIDP). Chi square test, non parametric test and binary Logistic regression model were used to analyze the influencing factors of oral health related quality of life in senior primary school students.@*Results@#The prevalence of oral problems affecting the quality of daily life was 70.00%, and the severe impact rate was 15.06%. Oral feeding was the most affected (57.95%). The Child-OIDP score was (7.49±8.57). Binary Logistic regression analysis showed that mother s education level, self rated teeth and oral conditions, bruised tooth, toothache in the past year, and gingival bleeding in the past 2 weeks were significantly associated with the incidence of Child-OIDP ( OR=1.86-5.00, P <0.05).@*Conclusion@#It is common that oral problems affect the quality of daily life of senior primary school students in Bengbu. Families and schools should strengthen oral health knowledge education and behavior guidance, so as to reduce the impact of oral problems on daily life among senior primary school students.

The impact of health related quality of life for children and adolescents aged 8-15 years in Nanjing / 中国学校卫生

Objective@#To investigate the impact of COVID-19 infection and health related behaviors on the health related quality of life of children and adolescents aged 8-15 years in Nanjing, so as to provide a theoretical basis for improving HRQoL in children and adolescents.@*Methods@#From December 2022 to January 2023, a total of 2 398 students aged 8-15 years from the third grade of primary school to junior middle school in Nanjing were selected by multistage random cluster sampling. The 3 level EuroQol 5 dimension Questionnaire Youth Vension (EQ-5D-Y-3L) was completed by the respondents on their own, and the parents assisted in completing the rest of the questionnaire.@*Results@#The EuroQol-index(EQ-index) and Visual Analogue Scale (VAS) scores of being infected individuals were lower than those of uninfected and previously infected ( P <0.05). The proportion of being infected individuals reporting difficulty on "Pain/Discomfort" was higher than that of uninfected and previously infected individuals, and the proportion of reporting difficulty on "Mobility" was also higher than that of uninfected individuals ( P <0.05). Lack of parental companionship( OR=10.19, 95%CI =3.12-33.22), irregular breakfast consumption ( OR=10.63, 95%CI =3.20-35.25), and excessive screen time ( OR=8.24, 95%CI =3.02-22.51) increased the risk of difficulty on "Mobility" in being infected individuals ( P <0.05). Irregular breakfast consumption ( OR=1.93, 95%CI =1.31-2.84) and consumption of sweetened beverages and snacks (OR=1.56, 95%CI =1.17-2.10) increased the risk of having lower EQ index in previously infected individuals compared to uninfected individuals. Furthermore, consumption of sweetened beverages and snacks ( OR=1.57, 95%CI =1.21-2.05) and excessive screen time ( OR=1.49, 95%CI =1.12-1.98) also increased the risk of VAS scores being lower in previously infected individuals compared to uninfected individuals ( P <0.05).@*Conclusion@#The COVID-19 infection impairs HRQoL, and unhealthy behaviors deteriorate its negative impact. Healthy behaviors and lifestyles should be advocated to reduce the impact of COVID-19 infection on HRQoL.

The effect of rs 12145833 polymorphism of SDCCAG 8 gene on intervention of childhood obesity / 中国学校卫生

Objective@#To study the role of rs 12145833 polymorphism of SDCCAG 8 gene in the intervention of childhood obesity, so as to provide scientific basis for formulating personalized intervention measures based on genetic background in children with obesity.@*Methods@#From September 2018 to June 2019, a total of 393 children aged 8-10 years in Beijing were enrolled in a cluster randomized controlled trial. Eight schools were randomly allocated into intervention group and control group at a ratio of 1∶1. Saliva DNA samples were collected to detect rs 12145833 polymorphism of SDCCAG 8 gene. The intervention group received a comprehensive intervention, while the control group received usual practice. Intervention measures included diet improvement, sports, school amd family sport. The obesity related indicators were measured at baseline and after the end of intervention 1 academic year. Multiple linear regression and Logistic regression were used to analyze the interaction between genes and intervention on obesity indicators.@*Results@#In the intervention group, children with TT genotype of rs 12145833 of the SDCCAG 8 gene had less increase in systolic( β=4.56, 95%CI=1.84-7.28, P <0.01) and diastolic blood pressure( β=2.59, 95%CI=0.45-4.73, P <0.05) than those with GT and GG genotypes. In the control group, the systolic blood pressure of children with TT genotype increased more than those with GT and GG genotype( β=-2.86, 95%CI=-5.63--0.83, P <0.05). There was an interaction between rs 12145833 polymorphism of SDCCAG 8 gene and intervention on systolic blood pressure, diastolic blood pressure and body fat percentage in children( P <0.05).@*Conclusion@#Children with TT genotype of rs 12145833 in the SDCCAG 8 gene are more sensitive to obesity intervention than those with GG and GT genotypes, especially in the improvement of systolic blood pressure, diastolic blood pressure and body fat percentage. Further trials to study the role of rs 12145833 polymorphism of SDCCAG 8 gene in the intervention of childhood obesity among different ethnic populations are needed.

School lunch leftovers of primary and middle school students and its influencing factors in Ningbo / 中国学校卫生

Objective@#To analyze the situation and associated factors of school lunch leftovers of primary and middle school students in Ningbo, so as to provide a basis for formulating policies to improve the quality of nutritious meals and reduce the leftover meal rates.@*Methods@#During March to May of 2022, 20 primary and middle schools were selected from 10 districts in Ningbo, and 4 443 students were selected from grade 4 to 6 of primary school and grade 1 to 3 of middle school. A questionnaire was conducted among them for the students general situation and remaining meal situation.@*Results@#The total leftover rate was 62.4%, 7.9% of the students left rice every day, and 18.3% of the students left vegetables every day. The frequency of primary school students leftover food was lower than that of junior high school students ( χ 2=-2.18, P <0.05). Most of the students (68.3%) had only a little leftover food, half of the students (49.4%) had less than half leftovers, and the proportion of primary school students with large leftover food and leftovers was smaller than that of junior high school students ( χ 2=-2.05, -2.36, P <0.05). The main reason for students leftover food was "too much to eat" (accounting for 30.6%), and there was a statistical difference between primary school students and junior high school students in the composition of leftover food and leftovers ( χ 2=16.94, 14.28, P <0.05). The leftover rate of vegetables was the highest (54.5%) and the leftover rate of milk was the lowest (2.5%). Multivariate Logistic regression model showed that nutrition and food related courses during recent year, being aware the Chinese residents dietary guidelines, statisfaction with canteen food (general, more satisfied, very satisfied), reckoning school canteen food better than home food (almost, better than home) were less possibility to have leftover meals ( OR=0.79, 0.73, 0.57, 0.41, 0.26, 0.69, 0.82, P <0.05). Students chosed the meal after the teacher served the meal, the teacher divided meals and students who ate more frequently (4-6 times/week, 1 time/d, 2 times/d, ≥3 times/d) were more likely to have leftover meals ( OR=1.64, 2.23, 1.27, 1.21, 1.52, 1.44 , P < 0.05).@*Conclusion@#More than half of the students have leftovers. It should optimize the configuration of nutrition lunch, strengthen the education of nutrition knowledge and reduce the leftovers rate.