Korea Seroprevalence Study of Monitoring of SARS-COV-2 Antibody Retention and Transmission (K-SEROSMART): findings from national representative sample.

OBJECTIVES: We estimated the population prevalence of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including unreported infections, through a Korea Seroprevalence Study of Monitoring of SARS-CoV-2 Antibody Retention and Transmission (K-SEROSMART) in 258 communities throughout Korea. METHODS: In August 2022, a survey was conducted among 10,000 household members aged 5 years and older, in households selected through two stage probability random sampling. During face-to-face household interviews, participants self-reported their health status, COVID-19 diagnosis and vaccination history, and general characteristics. Subsequently, participants visited a community health center or medical clinic for blood sampling. Blood samples were analyzed for the presence of antibodies to spike proteins (anti-S) and antibodies to nucleocapsid proteins (anti-N) SARS-CoV-2 proteins using an electrochemiluminescence immunoassay. To estimate the population prevalence, the PROC SURVEYMEANS statistical procedure was employed, with weighting to reflect demographic data from July 2022. RESULTS: In total, 9,945 individuals from 5,041 households were surveyed across 258 communities, representing all basic local governments in Korea. The overall population-adjusted prevalence rates of anti-S and anti-N were 97.6% and 57.1%, respectively. Since the Korea Disease Control and Prevention Agency has reported a cumulative incidence of confirmed cases of 37.8% through July 31, 2022, the proportion of unreported infections among all COVID-19 infection was suggested to be 33.9%. CONCLUSIONS: The K-SEROSMART represents the first nationwide, community-based seroepidemiologic survey of COVID-19, confirming that most individuals possess antibodies to SARS-CoV-2 and that a significant number of unreported cases existed. Furthermore, this study lays the foundation for a surveillance system to continuously monitor transmission at the community level and the response to COVID-19.

National survey of periodontal diseases in adolescents and young adults in Morocco.

AIM: National surveys of periodontal diseases in children are rare. This study describes the first national survey of oral health of adolescents attending public schools in Morocco. We report the prevalence and demographic determinants of periodontal diseases, and generate population estimates for this young population. MATERIALS AND METHODS: This study used a multi-stage probability sample comprising 14,667 students in 87 schools and 520 classrooms, representative of students attending grades 6-12 (age 12-18 years) in Morocco. The students were interviewed and then examined clinically to assess their periodontal status, which was classified according to the 2017 World Workshop. In addition, the diagnosis of aggressive periodontitis (AgP) was assessed. RESULTS: Of approximately 3 million students in this age cohort, 12.3% (or approximately 360,894 subjects) had periodontitis and 46.9% (1.4 million) had gingivitis. They comprised 10.8%, 2.9%, and 6.1% subjects with periodontitis stage I, II, and III/IV, respectively; 5.0%, or 148,336 subjects, had AgP. The prevalence rates were not significantly different by gender or urban status. However, the prevalence of AgP was particularly high in certain regions of Morocco. CONCLUSIONS: The prevalence of staged periodontitis and AgP in this young population is among the highest reported in national surveys worldwide.

Are multiple-use bottles of chlorhexidine solutions at risk of contamination in joint replacement surgery?

INTRODUCTION: Chlorhexidine gluconate 2% w/v in isopropanol 70% solutions in multiple-use bottles is commonly used in surgery as a cost-effective method for skin disinfection. However, multiple-use bottles risk contamination. This study aims to test whether bacterial contamination of multiple-use bottles or their solutions occurs once open and on use between different patients. METHODS: Consecutive samples were taken each time a chlorhexidine bottle was used over a 7-day study period. Samples were tested using blood culture, agar plate and mass spectrometry. RESULTS: No growth was observed in 52 samples taken from 18 bottles inoculated into blood culture bottles. Four growths on agar plate culture were determined to be contaminants from the sampling process. CONCLUSIONS: This study supports the use of multiple-use bottled chlorhexidine solutions as safe and cost-effective in surgical practice.

Comparison of sampling designs from the two editions of the Brazilian National Health Survey, 2013 and 2019 / Comparação de desenhos amostrais das duas edições da Pesquisa Nacional de Saúde, 2013 e 2019 / Comparación entre diseños muestrales de las dos ediciones de la Encuesta Nacional de Salud Brasil, 2013 y 2019

Our objective is to describe the differences in the sampling plans of the two editions of the Brazilian National Health Survey (PNS 2013 and 2019) and to evaluate how the changes affected the coefficient of variation (CV) and the design effect (Deff) of some estimated indicators. Variables from different parts of the questionnaire were analyzed to cover proportions with different magnitudes. The prevalence of obesity was included in the analysis since anthropometry measurement in the 2019 survey was performed in a subsample. The value of the point estimate, CV, and the Deff were calculated for each indicator, considering the stratification of the primary sampling units, the weighting of the sampling units, and the clustering effect. The CV and the Deff were lower in the 2019 estimates for most indicators. Concerning the questionnaire indicators of all household members, the Deffs were high and reached values greater than 18 for having a health insurance plan. Regarding the indicators of the individual questionnaire, for the prevalence of obesity, the Deff ranged from 2.7 to 4.2, in 2013, and from 2.7 to 10.2, in 2019. The prevalence of hypertension and diabetes per Federative Unit had a higher CV and lower Deff. Expanding the sample size to meet the diverse health objectives and the high Deff are significant challenges for developing probabilistic household-based national survey. New probabilistic sampling strategies should be considered to reduce costs and clustering effects.

Nosso objetivo é descrever as diferenças nos desenhos amostrais das duas edições da Pesquisa Nacional de Saúde (PNS 2013 e 2019) e avaliar como suas mudanças afetaram o coeficiente de variação (CV) e o efeito do desenho (Deff) de alguns dos indicadores avaliados. Variáveis de diferentes partes do questionário foram analisadas para avaliar proporções com diferentes magnitudes. A prevalência de obesidade foi incluída na análise uma vez que a medição de antropometria na pesquisa de 2019 foi realizada em uma subamostra. Os valores do estimador pontual, CV e Deff foram calculados para cada indicador considerando a estratificação das unidades amostrais primárias, a ponderação das unidades amostrais, e o efeito do agrupamento. Para a maioria dos indicadores, CV e Deff foram menores nas estimativas de 2019. Em relação aos indicadores para todos os membros familiares, Deffs foram elevados e atingiram valores superiores a 18 para a posse de um plano de saúde. Quanto aos indicadores no questionário individual, Deff variou de 2,7 a 4,2 em 2013 e de 2,7 a 10,2 em 2019 para a prevalência de obesidade. A prevalência de hipertensão arterial e diabetes por Unidade Federativa apresentou CV maior e Deff menor. A expansão do tamanho da amostra para atender aos diversos objetivos de saúde e Deff altos são desafios expressivos para o desenvolvimento de uma pesquisa nacional domiciliar probabilística. Novas estratégias de amostragem probabilística devem ser consideradas para reduzir custos e efeitos do agrupamento.

Nuestro objetivo es describir las diferencias en los diseños muestrales de las dos ediciones de la Encuesta Nacional de Salud (PNS 2013 y 2019) y evaluar cómo sus cambios afectaron el coeficiente de variación (CV) y el efecto de diseño (Deff) de algunos de los indicadores evaluados. Se analizaron variables de diferentes partes del cuestionario para evaluar proporciones con diferentes magnitudes. La prevalencia de obesidad se incluyó en el análisis, ya que la medición de la antropometría en la encuesta de 2019 se realizó en una submuestra. Los valores del estimador puntual, CV y Deff se calcularon para cada indicador considerando la estratificación de las unidades de muestreo primarias, la ponderación de las unidades de muestreo y el efecto de agrupamiento. Para la mayoría de los indicadores, CV y Deff fueron más bajos en las estimaciones de 2019. En cuanto a los indicadores para todos los miembros de la familia, los Deff fueron altos y alcanzaron valores superiores a 18 por tener un plan de salud. En cuanto a los indicadores del cuestionario individual, Deff osciló entre 2,7 y 4,2 en 2013, y entre 2,7 y 10,2 en 2019 para la prevalencia de obesidad. La prevalencia de hipertensión arterial y diabetes por Unidad Federativa tuvo mayor CV y menor Deff. Un mayor tamaño de la muestra para cumplir con los diversos objetivos de salud y un alto valor de Deff son desafíos importantes para el desarrollo de una encuesta nacional domiciliar probabilística. Se deben considerar nuevas estrategias de muestreo probabilístico para reducir los costos y efectos de agrupamiento.

Limitations in representative sampling of unpaid caregivers from minority ethnocultural backgrounds in a population-based survey.

OBJECTIVE: Historically, persons from minority ethnic, religious and linguistic backgrounds have been un- or under-represented in population-based research studies. Emerging scholarship suggests challenges in representative sampling, particularly of minority ethnocultural groups, has been exacerbated by the COVID-19 pandemic. This research note offers additional insights concerning these challenges in the context of a population-based survey of unpaid caregivers conducted in Ontario, Canada, between August and December, 2020, the analysis of which is currently underway. RESULTS: Beyond limitations intrinsic to study design, including time and budget constraints, the study sample underrepresents unpaid caregivers from minority ethnocultural backgrounds due to differences in conceptions of caregiving across minority cultures, the time-consuming nature of caregiving that disproportionately affects minority groups, and a propensity to avoid research which is rooted in tokenism. These hypotheses are non-exhaustive, speculative and warrant further empirical investigation.

Sampling plan of the Brazilian National Survey on Child Nutrition (ENANI-2019): a population-based household survey / Plano amostral do Estudo Nacional de Alimentação e Nutrição Infantil (ENANI-2019): inquérito domiciliar de base populacional / Plan de muestreo del Estudio Nacional de Alimentación y Nutrición Infantil (ENANI-2019): encuesta domiciliaria de base poblacional

The article describes methodological aspects in defining the study population, sampling plan, and sample weigthing and calibration of effective sample of the Brazilian National Survey on Child Nutrition (ENANI-2019). This population-based household survey assessed breastfeeding and dietary intake, anthropometric assessment of nutritional status, and micronutrient deficiencies by blood biomarkers in children under five years of age. The data were obtained with a probability sample, with stratification by the five geographic regions in the country and clustering by census enumeration areas (CEAs). The sample was calculated at 15,000 households distributed in 1,500 CEAs, with 300 allocated in each of Brazil's five major geographic regions and 10 eligible households per CEA, sampled using inverse sampling. The required population parameters were thus estimated to reach the study's objectives. The basic sampling design weights were calculated as the inverse probabilities of the households' inclusion in the study. Imputation was used to compensate for non-response to items in the target variables, except for data on the blood biomarkers. Finally, calibration used population totals of children in 60 post-strata, defined by cross-classification of the following variables: major geographic region, sex, and age. The final sample included 14,558 children residing in 12,524 households, distributed in 1,382 CEAs in the 26 states of Brazil and the Federal District. The data from the ENANI-2019 survey will support strategies for the promotion and implementation of public policies for children under five years of age.

O objetivo deste artigo é descrever aspectos metodológicos referentes à definição da população da pesquisa, plano amostral, ponderação e calibração da amostra efetiva do Estudo Nacional de Alimentação e Nutrição Infantil (ENANI-2019). Trata-se de um inquérito populacional de base domiciliar que realizou avaliação do aleitamento materno e de consumo alimentar, avaliação antropométrica do estado nutricional, e avaliação das deficiências de micronutrientes mediante análise de biomarcadores sanguíneos em crianças menores de 5 anos de idade. Seus dados foram obtidos por meio de uma amostra probabilística domiciliar, com estratificação geográfica por macrorregião e conglomeração por setores censitários. A amostra foi dimensionada em 15.000 domicílios, distribuídos em 1.500 setores censitários, sendo 300 em cada macrorregião e 10 domicílios elegíveis por setor, através de amostragem inversa. Assim, estimaram-se os parâmetros populacionais requeridos para atingir os objetivos do estudo. Os pesos amostrais básicos do desenho foram calculados como inversos das probabilidades de inclusão dos domicílios na pesquisa. Para compensar a não resposta de itens das variáveis pesquisadas foi usada imputação, com exceção para os dados de biomarcadores sanguíneos. A calibração empregou totais populacionais de crianças para 60 pós-estratos definidos por cruzamento das variáveis macrorregião, sexo e idade. A amostra final compreendeu 14.558 crianças, residentes em 12.524 domicílios, distribuídos em 1.382 setores censitários nas 27 Unidades da Federação. Os dados do ENANI-2019 poderão subsidiar estratégias de promoção e implementação de políticas públicas para crianças menores de 5 anos.

El objetivo de este artículo es describir aspectos metodológicos referentes a definición de la población de la investigación, plan de muestreo, ponderación de la muestra y muestra efectiva del Estudio Nacional de Alimentación y Nutrición Infantil (ENANI-2019). Se trata de una encuesta poblacional de base domiciliaria, que realizó una evaluación de la lactancia materna y de consumo alimentario, así como una evaluación antropométrica del estado nutricional y de las deficiencias de micronutrientes, mediante análisis de biomarcadores sanguíneos en niños menores de cinco años de edad. Sus datos se obtuvieron mediante una muestra probabilística domiciliaria, con estratificación geográfica por macrorregión y conglomerados por sectores censitarios. La muestra se circunscribió a 15.000 domicilios, distribuidos en 1.500 sectores censitarios, encontrándose 300 en cada macrorregión, junto 10 domicilios elegibles por sector, a través de un muestreo inverso. De esta forma, se estimaron los parámetros poblacionales requeridos para alcanzar los objetivos del estudio. Los pesos básicos de las muestras del diseño se calcularon como inversos a las probabilidades de inclusión de los domicilios en la investigación. Para compensar la no respuesta de ítems de las variables investigadas se usó la imputación, con excepción de los datos con biomarcadores sanguíneos. La calibración empleó totales poblacionales de niños para los 60 post estratos, definidos mediante el cruce de las variables macrorregión, sexo y edad. La muestra final comprendió 14.558 niños, residentes en 12.524 domicilios, distribuidos en 1.382 sectores censitarios dentro de las 27 Unidades de la Federación. Los datos del ENANI-2019 podrán apoyar estrategias de promoción e implementación de políticas públicas para niños menores de cinco años.

Algunas consideraciones para el cálculo del tamaño muestral en investigaciones de las Ciencias Médicas / Some considerations for the calculation of the sample size in Medical Sciences research

RESUMEN El proceso de formación y superación permanente o continuada de los profesionales, como un principio de la Educación Médica, se articula con la integración docencia, asistencia e investigación. Para responder a las exigencias de la actividad investigativa, la búsqueda y el tratamiento de la información requiere de un estudio estadístico para que aflore la cualidad desde el análisis cuantitativo; para ello, es importante considerar que en todos los estudios de esta magnitud, la población total se hace muy engorrosa, cara y lenta, por lo que se deben emplear técnicas de muestreo para obtener información significativa con el uso de menos recursos y menor tiempo. El objetivo del presente trabajo es reflexionar sobre el uso del muestreo en las ciencias médicas. Se expone la fórmula del muestreo para media y varianza conocidas, se da una técnica para encontrar el número de elementos de la muestra inicial cuando no se tienen conocimientos previos de media y varianza; se estudia el muestreo aleatorio simple de proporciones con las probabilidades de éxito y fracaso p y q respectivamente, explicándose el caso cuando se tiene p = q = 0.5 para la obtención de un tamaño de la muestra máximo.

ABSTRACT The objective of this paper is to reflect some considerations on the use of sampling in health sciences, based on the need for professionals in these sciences to familiarize themselves with scientific research in their area of knowledge, from a scientific perspective, that makes it possible to investigate the health problems that are constantly developing. The process of Permanent and Continuous Training and Improvement of professionals, as a principle of Medical Education, is articulated with that of Teaching - Assistance and research, the search and treatment of information in this area of scientific knowledge, requires of a statistical study that emerges the quality from the quantitative analysis, for this, it is important to consider that in all studies of this magnitude, the total population becomes very cumbersome, expensive and slow, so sampling techniques should be used to Obtain meaningful information with the use of less resources and less time. The sampling formula for known mean and variance is presented, a technique is given to find the number of elements of the initial sample when there is no prior knowledge of mean and variance, simple random sampling of proportions with the probabilities of success is studied and failure p and q respectively, explaining the case when you have p = q = 0.5 to obtain a maximum sample size.

The effect of number of healthcare visits on study sample selection in electronic health record data.

INTRODUCTION: Few studies have addressed how to select a study sample when using electronic health record (EHR) data. OBJECTIVE: To examine how changing criterion for number of visits in EHR data required for inclusion in a study sample would impact one basic epidemiologic measure: estimates of disease period prevalence. METHODS: Year 2016 EHR data from three Midwestern health systems (Northwestern Medicine in Illinois, University of Iowa Health Care, and Froedtert & the Medical College of Wisconsin, all regional tertiary health care systems including hospitals and clinics) was used to examine how alternate definitions of the study sample, based on number of healthcare visits in one year, affected measures of disease period prevalence. In 2016, each of these health systems saw between 160,000 and 420,000 unique patients. Curated collections of ICD-9, ICD-10, and SNOMED codes (from CMS-approved electronic clinical quality measures) were used to define three diseases: acute myocardial infarction, asthma, and diabetic nephropathy). RESULTS: Across all health systems, increasing the minimum required number of visits to be included in the study sample monotonically increased crude period prevalence estimates. The rate at which prevalence estimates increased with number of visits varied across sites and across diseases. CONCLUSIONS: In addition to providing thorough descriptions of case definitions, when using EHR data authors must carefully describe how a study sample is identified and report data for a range of sample definitions, including minimum number of visits, so that others can assess the sensitivity of reported results to sample definition in EHR data.

[A convenience sampling questionnaire survey of the current status of diagnosis and treatment of endometriosis in China in 2018].

Objective: To further understand the current status of diagnosis and treatment of endometriosis in China, the implementation of guideline in different levels of hospitals, and the need for continuing education in endometriosis among primary doctors. Methods: The survey was conducted in the form of convenience sampling questionnaire among the Wechat public platform. The doctors were free to participate in the investigation without any reward. All questions answered were assessed as valid questionnaire. The datas were collected on the questionnaire network platform and analyzed by SPSS 19.0. Results: Totally 1 494 valid questionnaires were collected in this survey. 60.17% (899/1 494) of them were from tertiary hospital, and 32.60% (487/1 494) were from grade two hospital. Only the hospitals where 9.97% (149/1 494) participants based opened the specialist clinic for endometriosis. 70.35% (1 051/1 494) of participants said they had read the second edition of guideline for the diagnosis and treatment of endometriosis which published in 2015. The American Society for Reproductive Medicine (ASRM) staging system was adopted in the clinical practices of only 25.03% (374/1 494) participants. And 18.74% (280/1 494) participants used the endometriosis fertility index (EFI) scoring during the laparoscopic surgery for endometriosis with infertility. 45.18% (675/1 494) of participants said they had not attended any academic conference on endometriosis in the past six months. 64.46% (963/1 494) of the participants believed their diagnosis and treatment in practice should be improved and standardized. 87.15% (1 302/1 494) of the participants expressed the hope that more conferences or workshops on endometriosis would be held. Conclusions: At presents, the diagnosis and treatment of endometriosis in China has been greatly improved, but the implementation of guidelines and the new concept is still a long-term job. The specialist clinic are held only in a few hospitals. It's the expectation and voice of primary doctors to the association to organize the more academic congresses on endometriosis.

Characterization of female sex workers in Brazilian capitals, 2016 / Caracterización de las mujeres trabajadoras sexuales en las capitales brasileñas, 2016 / Caracterização de mulheres trabalhadoras do sexo em capitais brasileiras, 2016

Objective. To describe the characteristics of female sex workers (FSW) from 12 Brazilian cities. Methods. Cross-sectional study of Biological and Behavioral Surveillance Survey (BBSS) with FSW recruited by Respondent-Driven Sampling (RDS), in 2016. HIV prevalence, sociodemographic, behavioral, and variables related to sex work were estimated by city. Chi-square test was used to compare these distributions. Results. Among 4,328 FSW, HIV prevalence was 5.3% (95%CI 4.5;6.3), ranging from 0.2% (95% CI 0.0;1.2), in Campo Grande, to 18.2 (95%CI 13.2;24.7) in Salvador.  In half of the cities, HIV prevalence in the samples was >5.0%, while Campo Grande, Brasília and Belo Horizonte had prevalence rates <1.0%. Significant differences between cities were found in the distributions according to educational level, income, workplace, starting age of sex work, and illicit drugs use. Conclusion. The characteristics of the samples in each city were distinct and have influenced local HIV prevalence.

Objetivos. Describir las características de las mujeres trabajadoras sexuales (MTS) de 12 ciudades brasileñas. Métodos. Estudio transversal de vigilancia biológica y conductual con MTS reclutadas por Respondent-Driven Sampling, 2016. La prevalencia del VIH, las características sociodemográficas, de comportamiento y relacionadas con la profesión se estimaron por ciudad. Se utilizó chi-cuadrado para comparar essas distribuciones. Resultados. Entre 4,328 MTS, la prevalencia del VIH fue 5.3% (IC95% 4,5;6,3), variando de 0.2% (IC95% 0,0;1,2) en Campo Grande a 18.2% (IC95% 13,2;24,7) en Salvador.  En la mitad de las ciudades, la prevalencia del VIH fue >5.0%, mientras que Campo Grande, Brasíla y Belo Horizonte tuvieron  prevalencia <1.0%. Se encontraron diferencias significativas entre las ciudades en las distribuciones de acuerdo con la  escolaridad, ingresos, lugar de trabajo, edad de inicio del trabajo sexual y uso de drogas ilícitas. Conclusión. Las características de las muestras locales fueron  diferentes e influyeron en la prevalencia local del VIH. Palabras-clave: VIH; Trabajo Sexual; Muestreo; Red Social; Poblaciones Vulnerables; Brasil.

Objetivo. Descrever as características das mulheres trabalhadoras do sexo (MTS) de 12 capitais brasileiras. Métodos. Estudo transversal de vigilância biológica e comportamental com MTS recrutadas por respondent-driven sampling (RDS), em 2016. Foram estimadas, por cidade, as prevalências de HIV, características sociodemográficas, comportamentais e da profissão. Utilizou-se o teste de qui-quadrado para comparar essas distribuições. Resultados. Entre 4.328 MTS, a prevalência da infecção pelo HIV foi de 5,3% (IC95% 4,5;6,3), variando de 0,2% (IC95% 0,0;1,2) em Campo Grande, a 18,2% (IC95% 13,2;24,7) em Salvador. Em metade das cidades, a prevalência de HIV nas amostras foi >5,0%, enquanto Campo Grande, Brasília e Belo Horizonte apresentaram prevalências <1,0%. Diferenças significativas entre as cidades foram encontradas nas distribuições segundo escolaridade, renda, local de trabalho, idade de início do trabalho sexual, e uso de drogas ilícitas. Conclusão. As características das amostras em cada cidade foram distintas, e influenciaram a prevalência local de HIV.

Assessment of transparent and reproducible research practices in the psychiatry literature.

BACKGROUND: Reproducibility is a cornerstone of scientific advancement; however, many published works may lack the core components needed for study reproducibility. AIMS: In this study, we evaluate the state of transparency and reproducibility in the field of psychiatry using specific indicators as proxies for these practices. METHODS: An increasing number of publications have investigated indicators of reproducibility, including research by Harwicke et al, from which we based the methodology for our observational, cross-sectional study. From a random 5-year sample of 300 publications in PubMed-indexed psychiatry journals, two researchers extracted data in a duplicate, blinded fashion using a piloted Google form. The publications were examined for indicators of reproducibility and transparency, which included availability of: materials, data, protocol, analysis script, open-access, conflict of interest, funding and online preregistration. RESULTS: This study ultimately evaluated 296 randomly-selected publications with a 3.20 median impact factor. Only 107 were available online. Most primary authors originated from USA, UK and the Netherlands. The top three publication types were cohort studies, surveys and clinical trials. Regarding indicators of reproducibility, 17 publications gave access to necessary materials, four provided in-depth protocol and one contained raw data required to reproduce the outcomes. One publication offered its analysis script on request; four provided a protocol availability statement. Only 107 publications were publicly available: 13 were registered in online repositories and four, ten and eight publications included their hypothesis, methods and analysis, respectively. Conflict of interest was addressed by 177 and reported by 31 publications. Of 185 publications with a funding statement, 153 publications were funded and 32 were unfunded. CONCLUSIONS: Currently, Psychiatry research has significant potential to improve adherence to reproducibility and transparency practices. Thus, this study presents a reference point for the state of reproducibility and transparency in Psychiatry literature. Future assessments are recommended to evaluate and encourage progress.

Using a National Register as a Sampling Frame from the Perspective of an Early Career Researcher.

BACKGROUND: Selection of a sampling frame is a key component of conducting survey-based research. This article discusses the use of a national register, the Dental Register, as a sampling frame from the perspective of an early career researcher. METHODS: While conducting a survey-based study of a nationally representative sample of general dentists in Ireland, I documented the difficulties I encountered while using a national register. As a research assistant and novice researcher, I recorded the advantages and disadvantages I discovered over the course of the project and its impact on the study. CONCLUSION: While using a national register has advantages such as a readily available sample of the target population, there are also inherent disadvantages depending on the manner in which records are recorded. KNOWLEDGE TRANSFER STATEMENT: This article can be used as an informative guide to researchers in selecting a sampling frame, with particular emphasis on the use of a national register in selecting a nationally representative sample of dentists.

Ependymal fluorescence in fluorescence-guided resection of malignant glioma: a systematic review.

BACKGROUND: Fluorescence in the ventricular wall or the ependyma during fluorescence-guided resection (FGR) of malignant glioma is commonly observed when malignant gliomas infiltrate the ventricles. However, the underlying pathophysiology and clinical importance are largely unknown but may play a role in deciding whether to continue resection into the ventricles or not. Here, we systematically review available data regarding ependymal fluorescence in FGR using five aminolevulinic acid (5-ALA) and sodium fluorescein (SF). METHODS: A literature search on MEDLINE, EMBASE, and WEB OF SCIENCE was performed using the following headings and search operators: ependy* fluorescence AND (5-ALA OR five aminolevulinic acid), ventric* wall fluorescence AND (5-ALA OR five aminolevulinic acid), ependy* fluorescence AND fluorescein, and ventric* wall fluorescence AND fluorescein. Both authors analyzed abstracts independently. Included articles were further reviewed for prevalence of ependymal fluorescence, patterns of fluorescence, and histopathological characteristics of sampled tissues as well as radiological signs of ependymal fluorescence. Results are reported according to the PRISMA statement. RESULTS: Of 202 records identified, 6 studies were included compiling a total number of 198 patients treated with FGR using 5-ALA. No study on ependymal fluorescence after administration of SF was found. Overall prevalence of ependymal fluorescence was 61.4%. A total of 54.5% of cases were found to be positive for tumor cells. A total of 25.5% of patients with ependymal fluorescence were related to contrast enhancement in ventricular walls. CONCLUSIONS: The phenomenon of ventricular wall fluorescence in 5-ALA-derived fluorescence-guided resection of malignant glioma is poorly understood and not always may fluorescence represent tumor infiltration. A larger scale prospective sampling study with molecular analyses is currently ongoing and will hopefully provide further insight into pathophysiology and clinical implications of ependymal fluorescence.

Infestation index of Drosophila suzukii (Diptera: Drosophilidae) in small fruit in southern Brazil / Índice de infestação de Drosophila suzukii (Diptera: Drosophilidae) em pequenas frutas no sul do Brasil

The spotted-wing drosophila, Drosophila suzukii Matsumura, is considered the main insect pest of small fruit in the world. Identifying susceptible hosts is essential to develop management strategies. The aim of this study was to verify the level of D. suzukii infestation in blackberry, blueberry, strawberry, cattley guava and Surinam cherry fruits cultivated in the southern region in Brazil, and to determine the infestation index (II) per fruit. The studies were carried out during two harvests (2015/16 and 2016/17) in three areas with organic cultivation of small fruit. The highest level of D. suzukii natural infestation was observed in blackberry (40 to 65% infestation), and strawberry (approximately 30% infestation) fruits. In contrast, blueberries were less preferred (< 7% infestation). For native fruit of the region (cattley guava and Surinam cherry), it was also verified infestation of the fly, demonstrating they are hosts for multiplication in the off-season periods of the other crops. In relation to II, blackberry and Surinam cherry provided a higher average number of insects per gram of fruit (≈ 1.6 adults of D. suzukii). In contrast, blueberries and cattley guava had the lowest insect ratio per gram of fruit (≈ 0.7 adults per gram). The period between late spring to mid-autumn was considered ideal for the pest occurrence in the field. The knowledge of natural infestation levels is essential for understanding the behavior of the pest in the field, which will assist in the design of management strategies.(AU)

A drosófila-da-asa-manchada, Drosophila suzukii Matsumura, é considerada o principal inseto-praga de pequenos frutos no mundo. A identificação de hospedeiros suscetíveis é essencial para o desenvolvimento de estratégias de manejo. O objetivo deste estudo foi verificar o nível de infestação de D. suzukii em frutos de amoreira-preta, mirtileiro, morangueiro, araçazeiro e pitangueira cultivados na região no sul do Brasil e determinar os índices de infestação (II) por fruto. Os estudos foram realizados durante duas safras (2015/16 e 2016/17) em três áreas com cultivo orgânico de pequenas frutas. O maior nível de infestação natural de D. suzukii foi observado em amora-preta (40 a 65% de infestação) e morango (aproximadamente 30% de infestação). Em contraste, o mirtilo foi menos preferido (< 7% de infestação). Para as frutas nativas da região (araçá e pitanga), também ocorreu infestação da mosca, demonstrando serem hospedeiros potenciais para a multiplicação da praga nos períodos de entressafras. Em relação ao II, amoras e pitangas proporcionaram um maior número médio de insetos por grama de fruto (≈ 1,6 adultos de D. suzukii). Por outro lado, mirtilos e araçás apresentaram a menor relação de insetos emergidos por gramas de frutos (≈ 0,7 adultos por grama). O período entre final da primavera até meados do outono foi considerado ideal para a ocorrência da praga no campo. O conhecimento dos níveis de infestação natural é fundamental para o entendimento do comportamento da praga no campo, o que auxiliará no delineamento de estratégias de manejo.(AU)

Caracterização de mulheres trabalhadoras do sexo em capitais brasileiras, 2016 / Caracterización de las mujeres trabajadoras sexuales en las capitales brasileñas, 2016 / Characterization of female sex workers in Brazilian state capitals, 2016

Objetivo: Descrever as características das mulheres trabalhadoras do sexo (MTS) de 12 capitais brasileiras. Métodos: Estudo transversal de vigilância biológica e comportamental com MTS recrutadas por respondent-driven sampling (RDS), em 2016. Foram estimadas, por cidade, as prevalências de HIV, características sociodemográficas, comportamentais e da profissão. Utilizou-se o teste do Qui-Quadrado para comparar essas distribuições. Resultados: Entre 4.328 MTS, a prevalência da infecção pelo HIV foi de 5,3% (IC95% 4,5;6,3), variando de 0,2% (IC95% 0,0;1,2), em Campo Grande, a 18,2% (IC95%13,2;24,7) em Salvador. Em metade das cidades, a prevalência de HIV nas amostras foi >5,0%, enquanto Campo Grande, Brasília e Belo Horizonte apresentaram prevalências <1,0%. Diferenças significativas entre as cidades foram encontradas nas distribuições segundo escolaridade, renda, local de trabalho, idade de início do trabalho sexual, e uso de drogas ilícitas. Conclusão: As características das amostras em cada cidade foram distintas, e influenciaram a prevalência local de HIV.

Objetivos: Describir las características de las mujeres trabajadoras sexuales (MTS) de 12 ciudades brasileñas. Métodos: Estudio transversal de vigilancia biológica y conductual con MTS reclutadas por Respondent-Driven Sampling (RDS) 2016. La prevalencia del VIH, las características sociodemográficas, de comportamiento y relacionadas con la profesión se estimaron por ciudad. Se utilizó la prueba de Chi cuadrado para comparar esas distribuciones. Resultados: Entre 4,328 MTS, la prevalencia del VIH fue 5,3% (IC95%4,5; 6,3), variando de 0,2% (IC95% 0,0;1,2) en Campo Grande a 18,2% (IC95% 13,2; 24,7) en Salvador. En la mitad de las ciudades, la prevalencia del VIH fue >5,0%, mientras que Campo Grande, Brasíla y Belo Horizonte tuvieron prevalencia de, <1,0%. Se encontraron diferencias significativas entre las ciudades en las distribuciones, de acuerdo con la escolaridad, ingresos, lugar de trabajo, edad de inicio del trabajo sexual y uso de drogas ilícitas. Conclusión: Las características de las muestras locales fueron diferentes e influyeron en la prevalencia local del VIH.

Objective: To describe the characteristics of female sex workers (FSW) in 12 Brazilian cities. Methods: This was a cross-sectional biological and behavioral surveillance study with FSW recruited by respondent-driven sampling (RDS) in 2016. HIV prevalence, sociodemographic, behavioral and sex work profession variables were estimated by city. The chi-square test was used to compare these distributions. Results: Among 4,328 FSW, HIV prevalence was 5.3% (95%CI 4.5;6.3), ranging from 0.2% (95% CI 0.0;1.2), in Campo Grande, to 18.2 (95%CI 13.2;24.7) in Salvador. In half of the cities, HIV prevalence in the samples was >5.0%, while Campo Grande, Brasília and Belo Horizonte had prevalence rates <1.0%. Significant differences between cities were found in distributions according to educational level, income, workplace, age sex work started, and illicit drug use. Conclusion: The characteristics of the samples in each city were distinct and have influenced local HIV prevalence.

Reluctance and Willingness for Organ Donation After Death Among the Slovene General Population.

INTRODUCTION: The paper presents the findings of the first large-scale survey on post-mortem organ donation among the general Slovenian population. It focuses on the reported donation willingness, the barriers to joining the register of organ donors and the position towards consent to donate organs of deceased relatives. METHODS: A face-to-face survey was conducted on a probability sample of 1,076 Slovenian residents between October and December 2017. The performed analyses included estimations of means and proportions for target variables, an evaluation of between-group differences and a partial proportional odds model to study the relations between organ donation willingness and socio-demographic characteristics. RESULTS: The mean reported willingness to donate one's own organs after death was 3.77 on a 5-point scale, with less than a third of respondents claiming to be certainly willing. Only 6% of those at least tentatively willing to donate organs were certain to join the register of organ donors in the future. The most frequently reported barriers to registration were unfamiliarity with the procedure and a lack of considering it beforehand. The reported willingness to donate organs of a deceased relative strongly depended on the knowledge of the relative's wishes, yet 80% of the respondents did not discuss their wishes with any family members. CONCLUSIONS: The findings confirm the gap between the reported donation willingness and joining the register of donors. Future post-mortem organ donation strategies need to consider socio-demographic and attitudinal factors of donation willingness and help stimulate the communication about organ donation wishes between family members.

Using a HIV registry to develop accurate estimates for the HIV care cascade - the Singapore experience.

INTRODUCTION: Achieving UNAIDS 90-90-90 targets is a crucial step towards ending the AIDS epidemic. Many countries have published estimates of care cascades, although often with methodological limitations. We describe an approach that used the national HIV registry as a starting-point to determine the HIV care cascade and resulting UNAIDS 90-90-90 estimates for Singapore in 2014. METHODS: HIV is a legally notifiable disease in Singapore. The anonymized HIV registry data provided for a back-calculation model from the European Centre for Disease Prevention and Control to obtain 2014 estimates for the total number of persons living with HIV (PLHIV), and the count in the registry for proportions diagnosed with HIV and linked to care. Using additional data collected for a simple random sample from the registry, outcomes in 2015 and 2016 were ascertained retrospectively to derive proportions for those retained in care, on antiretroviral therapy, and achieved viral suppression. Findings were extrapolated to derive national estimates and UN90-90-90 estimates. Bootstrapped samples from the model and sample were used to derive 95% confidence intervals. RESULTS: An estimated 6900 (95% CI 6650, 7050) persons were living with HIV and AIDS in 2014. Of these, 4948 were diagnosed with HIV, and 4820 had been linked to care. The random sample of 500 persons was further analysed, and of these, 87.2% were retained in care, 84.6% on antiretroviral therapy, and 79.6% had suppressed viral loads. The proportions of HIV-infected individuals on antiretroviral therapy and achieving viral suppression were 60.7% (95% CI 58.4, 63.6) and 57.1% (95% CI 55.0, 60.5) respectively. The corresponding UNAIDS 90-90-90 estimates were 71.7% (95% CI 70.0, 74.2) of all persons diagnosed; 84.6% (95% CI 81.6, 87.4) of diagnosed persons being on antiretroviral therapy, and 94.1% (95% CI 91.6, 96.2) of persons on therapy having achieved viral suppression. CONCLUSIONS: A national HIV registry, alongside back-calculation and additional data from a sample, can be used to estimate attainment of UNAIDS 90-90-90 targets and identify system gaps. The registry had advantages of providing a well-established, comprehensive capture of diagnosed persons and easily accessible data. The same approach can be used elsewhere if similar data are available.

[Cause and control of non-sampling error in China National Human Biomonitoring Program].

The size of the non-sampling error is directly related to the accuracy and reliability of the sampling survey result. This paper studied the non-sampling errors generated during the sampling process of the China National Human Biomonitoring Program(CNBP), mainly including the sampling frame error, non-response error and measurement error. The program reduced the influence of the non-sampling error on the quality of the survey effectively by scientifically designing the sampling scheme and questionnaire, strengthening investigator trainings and standardizing the data review, which could be used to provide reference for the control of non-sampling errors in public health monitoring projects in China.

Population-based assessment of health, healthcare utilisation, and specific needs of Syrian migrants in Germany: what is the best sampling method?

BACKGROUND: Studies elucidating health-related information and special needs of Syrian migrants living in Germany are urgently required. However, data is scarce and finding appropriate sampling strategies to obtain representative results is challenging. In order to increase survey response in hard-to-reach populations, new methods were developed. One of them is respondent-driven sampling (RDS), a network sampling technique. We aimed to assess if respondent-driven sampling is a better approach to recruit Syrian migrants for health research than classical random sampling via the population registry. METHODS: A cross-sectional study was conducted in Munich between April and June 2017 inviting adults (18+ years) born in Syria to answer an online questionnaire asking for sociodemographic and health-related information. Recruitment of participants was done using a) random sampling via the population registry (PR) and b) RDS. The two study populations recruited via respondent-driven sampling and the population registry were compared to a sample drawn from the population registry with respect to gender and citizenship. In addition, the two study populations were compared to each other regarding self-reported health status, healthcare utilisation, lifestyle factors, social network size, and acculturation. RESULTS: Of 374 persons randomly drawn from the population registry, 49 individuals answered the questionnaire completely (response: 13.1%) while via RDS 195 participants were recruited by 16 seeds. More persons possessed German citizenship in the total sample (20.5, 95% CI: 16.6 to 24.8%) and in the PR study population (28.6, 95% CI: 16.6 to 43.3%) than in the study population (0.5, 95% CI: 0.1 to 1.5%). Participants recruited via the population registry were older, smoked less, reported more often to hold a university degree, and indicated a higher prevalence of chronic diseases, more frequent healthcare utilisation, higher scores of acculturation as well as a larger social network compared to the study population obtained via RDS. CONCLUSIONS: Response was very low in the PR sample. The number of participants recruited via RDS was larger and led to a study population with substantially different characteristics. Our study thus indicates that RDS is a useful way to gain access to specific subgroups that are hard to reach via traditional random sampling.

Sampling strategy of an epidemiological survey using a satellite image program

ABSTRACT OBJECTIVE To describe the sampling strategy of an epidemiological survey with the aid of satellite images, including details of the multistage probability sampling process. METHODS A probability sample of individuals living in the rural area of Rosário do Sul, state of Rio Grande do Sul, Brazil, aged 15 years old or more, was evaluated. Participants answered questionnaires (medical history, sociodemographic characteristics, habits, alcohol use, quality of life, stress, rumination, and self-perceived periodontal diseases), and were subjected to clinical oral examinations as well as anthropometric measurements (blood pressure, height, weight, abdominal and waist circumferences). Oral evaluation comprehended a complete periodontal exam at six sites per tooth, including the following assessments: furcation involvement; dental abrasion; tooth decay, including the indexing of missing and filled surfaces; O'Brien index; gingival abrasion; oral cavity and lip lesions; complete periapical radiographic exam, and use of prostheses. Besides this oral clinical approach, subgingival plaque, crevicular gingival fluid, saliva, and blood samples were collected. Examiners were trained and calibrated during previous evaluations. A pilot study allowed the logistic of the performed exams to be adjusted as needed. RESULTS Among 1,087 eligible individuals, 688 were examined (63.3%). Age, sex, and skin color data were compared to data from the last demographic census (2010) of the Brazilian Institute of Geography and Statistics, which served to validate the sampling strategy. CONCLUSIONS The careful methods used in this study, in which satellite images were used in the delimitation of epidemiological areas, ensure the quality of the estimates obtained and allow for these estimates to be used in oral health surveillance and health policies improvements.