Epidemiology Biostatistics and Public Health最新文献_第6页

Two-stage re-estimation adaptive design: a simulation study 两阶段重估自适应设计的仿真研究

Epidemiology Biostatistics and Public Health Pub Date : 2022-06-30 DOI: 10.2427/8862

F. Galli, L. Mariani

{"title":"Two-stage re-estimation adaptive design: a simulation study","authors":"F. Galli, L. Mariani","doi":"10.2427/8862","DOIUrl":"https://doi.org/10.2427/8862","url":null,"abstract":" \u0000 \u0000 \u0000Background: adaptive clinical trial design has been proposed as a promising new approach to improve the drug discovery process. Among the many options available, adaptive sample size re-estimation is of great interest mainly because of its ability to avoid a large ‘up-front’ commitment of resources. In this simulation study, we investigate the statistical properties of two-stage sample size re-estimation designs in terms of type I error control, study power and sample size, in comparison with the fixed-sample study. \u0000Methods: we simulated a balanced two-arm trial aimed at comparing two means of normally distributed data, using the inverse normal method to combine the results of each stage, and considering scenarios jointly defined by the following factors: the sample size re-estimation method, the information fraction, the type of group sequential boundaries and the use of futility stopping. Calculations were performed using the statistical software SAS™ (version 9.2). \u0000Results: under the null hypothesis, any type of adaptive design considered maintained the prefixed type I error rate, but futility stopping was required to avoid the unwanted increase in sample size. When deviating from the null hypothesis, the gain in power usually achieved with the adaptive design and its performance in terms of sample size were influenced by the specific design options considered. \u0000Conclusions: we show that adaptive designs incorporating futility stopping, a sufficiently high information fraction (50-70%) and the conditional power method for sample size re-estimation have good statistical properties, which include a gain in power when trial results are less favourable than anticipated. \u0000 \u0000","PeriodicalId":45811,"journal":{"name":"Epidemiology Biostatistics and Public Health","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73914798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Description of survival data extended to the case of competing risks: a teaching approach based on frequency tables 生存数据的描述扩展到竞争风险的情况:基于频率表的教学方法

Epidemiology Biostatistics and Public Health Pub Date : 2022-06-30 DOI: 10.2427/8874

D. Bernasconi, L. Antolini

{"title":"Description of survival data extended to the case of competing risks: a teaching approach based on frequency tables","authors":"D. Bernasconi, L. Antolini","doi":"10.2427/8874","DOIUrl":"https://doi.org/10.2427/8874","url":null,"abstract":"Survival analysis is a powerful statistical tool to study failure-time data. In introductory courses students learn how to describe right-censored survival time data using the product-limit estimator of the survival function on a given end-point relying on a product of conditional survival probabilities. In the case of a composite end-point, the next step is to account for the presence of competing risks. The complement to one of the survival function is decomposed into the sum of cause-specific incidences, which are obtained as sum of unconditional probabilities due to the single competing risk. However, this algebraic decomposition is not straightforward, given the difference between the structure of the involved estimators. In addition, one is tempted to use the Kaplan-Meier estimator, leading to an erroneous decomposition of the overall incidence. Here we discuss a simple reinterpretation of the Kaplan-Meier formula in terms of sum of non-conditional probabilities of developing the end-point in time, adjusted for the presence of censoring. This approach could be used for describing survival data through simple frequency tables which are directly generalized to the case of competing risks. In addition, it makes clear how the estimation of the single cause-specific incidence through the Kaplan-Meier estimator, simply considering the occurrence of competing events as censored data, leads to an overestimation of the cause-specific incidence. Two examples are provided to support the explanation: the first one, could help to clarify the procedure described by the formulas; the second one, simulates real data in order to present graphically the results.","PeriodicalId":45811,"journal":{"name":"Epidemiology Biostatistics and Public Health","volume":"28 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81636005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Integrating clinicians’ opinion in the Bayesian meta-analysis of observational studies: the case of risk factors for falls in community-dwelling older people 在观察性研究的贝叶斯荟萃分析中整合临床医生的意见:社区居住老年人跌倒的危险因素的案例

Epidemiology Biostatistics and Public Health Pub Date : 2022-06-30 DOI: 10.2427/8909

S. Deandrea, E. Negri, F. Ruggeri

{"title":"Integrating clinicians’ opinion in the Bayesian meta-analysis of observational studies: the case of risk factors for falls in community-dwelling older people","authors":"S. Deandrea, E. Negri, F. Ruggeri","doi":"10.2427/8909","DOIUrl":"https://doi.org/10.2427/8909","url":null,"abstract":"\u0000Background: despite the widespread application of Bayesian methods in meta-analysis, the incorporation of clinical informative priors based upon expert opinion is rare. \u0000Methods: a questionnaire to elicit beliefs about five risk factors for falls in older people was administered to a sample of geriatricians and general practitioners (GPs). The experts were asked to provide a point estimate and upper and lower limits of each relative risk. The elicited opinions were translated into different prior distributions and included in a Bayesian meta-analysis of prospective studies. Frequentist, Bayesian non-informative and fully Bayesian approaches were compared. \u0000Results: almost all the clinicians provided the requested information. In most cases, the variability across published studies was greater or similar to that across clinicians. Geriatricians provided more consistent estimates than GPs. When fewer studies were available, the use of the informative prior provided by geriatricians reduced the width of the credibility interval with respect to the frequentist or Bayesian non-informative approaches. Enthusiastic and skeptical priors led to results strongly driven by the prior distribution. \u0000Conclusions: this study presents a feasible method for belief elicitation and Bayesian priors’ assessment. The inclusion of external information showed to be useful when only few and/or heterogeneous studies were available from the literature. \u0000","PeriodicalId":45811,"journal":{"name":"Epidemiology Biostatistics and Public Health","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86500200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluating the effect of organization and context on technical efficiency: a second-stage DEA analysis of Italian hospitals 评价组织和环境对技术效率的影响:意大利医院的第二阶段DEA分析

Epidemiology Biostatistics and Public Health Pub Date : 2022-06-30 DOI: 10.2427/8785

D. Matranga, F. Bono, A. Casuccio, A. Firenze, Laura Marsala, R. Giaimo, F. Sapienza, F. Vitale

{"title":"Evaluating the effect of organization and context on technical efficiency: a second-stage DEA analysis of Italian hospitals","authors":"D. Matranga, F. Bono, A. Casuccio, A. Firenze, Laura Marsala, R. Giaimo, F. Sapienza, F. Vitale","doi":"10.2427/8785","DOIUrl":"https://doi.org/10.2427/8785","url":null,"abstract":"Objective: the purpose of this study was to compare the technical efficiency of Italian hospitals at a regional level and to examine if differences could be explained by organisational and contextual factors. Technical efficiency was defined as the ability of the operating units evaluated to use optimal resource levels for their level of output. \u0000Methods: the effect of external factors was explored through a second stage Data Envelopment Analysis (DEA). Efficiency scores were calculated for each hospital using the DEA method (Stage I). Through Tobit regression analysis, the estimated efficiency scores were regressed against a set of organisational and contextual characteristics beyond managerial control, which reflected differences in the population demographics and regional health expenditure (Stage II). Stage I and Stage II efficiency scores were compared in order to indirectly assess managerial contribution in relation to hospital efficiency. \u0000Results: the highest efficiency (M±SD) was observed in hospitals in the North-West (75.7±15.1), followed by those in the North-East (75.5±15.1), Central Italy (73.9±16.4) and then Southern Italy (70.6±17.9). Hospital Trusts (HTs) were shown to be more technically efficient than Local Public Hospitals (LPHs). Organisational and contextual indicators were statistically significantly different at Tobit regression analysis for HTs and LPHs. Emilia Romagna and Lombardia were the regions whose management contributed to increased efficiency. \u0000Conclusions: in our study, the distribution of regions according to technical efficiency only partly reflected the North-South gradient shown by other studies regarding the gap of expenditure. The important role of organisation and environment in establishing efficiency differences among hospitals was demonstrated.","PeriodicalId":45811,"journal":{"name":"Epidemiology Biostatistics and Public Health","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77817884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

Nutritional status among the children living in predominantly tribal block of Jhadol in district Udaipur, Rajasthan, India: A cross sectional study 印度拉贾斯坦邦乌代普尔地区贾多尔主要部落街区儿童的营养状况:一项横断面研究

Epidemiology Biostatistics and Public Health Pub Date : 2022-06-16 DOI: 10.2427/8893

Shahnawaz, J. Singh

{"title":"Nutritional status among the children living in predominantly tribal block of Jhadol in district Udaipur, Rajasthan, India: A cross sectional study","authors":"Shahnawaz, J. Singh","doi":"10.2427/8893","DOIUrl":"https://doi.org/10.2427/8893","url":null,"abstract":"\u0000Background: India has achieved remarkable economic progress in last couple of decades but the fruit of progress has failed to assure the better nutritional status to our children. The child nutritional situation remains grim for most of the states, especially in the tribal region. This paper is an attempt to measure the extent of under nutrition in terms of Height/Length-for-age (stunting), Weight-for-height/Length (wasting), and Weight-for-age (underweight) for children less than five year old in predominantly tribal block Jhadol of district Udaipur, Rajasthan, India. \u0000 \u0000Methods: World Health Organization (WHO) child growth standard has been used as reference population to measure the percentage prevalence of stunting, wasting and underweight from its median. Total of 1286 children (623male and 663female) have been considered for this study. WHO Anthro software has been used for analysis and interpretation of results. \u0000Results: The results showing the severe undernourishment among the children in this part of Rajasthan. 63% children are moderate to severely stunted (short for age), 46% has been found out to acutely malnourished and the composite index weight-for-age showing that 69% children is moderate to severely underweight. Against the popular facts that girls are more malnourished, boys of Jhadol block reported to be more undernourished. \u0000Conclusion: The high prevalence of chronic malnourishment in this part of Rajasthan is a matter of grave concern. This paper calls for a region specific policy based on holistic approach of better healthcare, ensuring food security, access to drinking water, sanitation. \u0000","PeriodicalId":45811,"journal":{"name":"Epidemiology Biostatistics and Public Health","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81716227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Luigi Mangiagalli

Epidemiology Biostatistics and Public Health Pub Date : 2022-06-16 DOI: 10.1159/000306030

P. Crosignani, C. La Vecchia

引用次数: 0

Prenatal genetic counselling: issues and perspectives for pre-conceptional health care in Emilia Romagna (Northern Italy) 产前遗传咨询:艾米利亚罗马涅(意大利北部)孕前保健的问题和观点

Epidemiology Biostatistics and Public Health Pub Date : 2022-06-16 DOI: 10.2427/8870

M. Lucci, G. Astolfi, S. Bigoni, A. Baroncini, O. Calabrese, A. Ferlini, G. Parmeggiani, E. Pompili, M. Seri, E. Calzolari

{"title":"Prenatal genetic counselling: issues and perspectives for pre-conceptional health care in Emilia Romagna (Northern Italy)","authors":"M. Lucci, G. Astolfi, S. Bigoni, A. Baroncini, O. Calabrese, A. Ferlini, G. Parmeggiani, E. Pompili, M. Seri, E. Calzolari","doi":"10.2427/8870","DOIUrl":"https://doi.org/10.2427/8870","url":null,"abstract":"\u0000Background: there are many reasons why a couple may seek specialist genetic counselling about foetal risk. The referral for prenatal genetic counselling of women with a known risk factor during pregnancy has many disadvantages. Despite this, 10-20% of women seek counselling when already pregnant. \u0000Methods: data on 804 pregnant women out of 2 158 (37.3%) referred for genetic counselling in 2010 to three Clinical Genetic Services were retrospectively analysed. Patients referred only for advanced maternal age were analysed in a separate study. \u0000Results: the 804 pregnant women were referred for 932 counselling issues. 325 issues (34.9%) were identified during pregnancy and 607 (65.1%) were pre-existing. 81.2% of Italians compared to 41.8% of the non-Italians (P<0.01) had access to counselling before 13 weeks of gestation for risk factors present before pregnancy. An accurate genetic diagnosis was available in 25.0% of cases. In 21.7% of the cases an elevated a priori risk of >10% for the unborn child was established. \u0000Conclusions: genetic services provide 37.3% of counselling to pregnant women. Referral for genetic counselling during pregnancy can require considerable resources and pose significant ethical and organizational challenges. New models of pregnancy care in the community need to be developed. General practitioners and gynaecologists have an important role in the referral and in the defence of equity of access and a more structured approach to the participation of medical geneticists to primary practice should be considered. \u0000","PeriodicalId":45811,"journal":{"name":"Epidemiology Biostatistics and Public Health","volume":"122 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75684183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Validation of a questionnaire for young women to assess knowledge, attitudes and behaviors towards cervical screening and vaccination against HPV: survey among an Italian sample 一份评估年轻妇女对子宫颈筛查和HPV疫苗接种的知识、态度和行为的问卷的验证:意大利样本调查

Epidemiology Biostatistics and Public Health Pub Date : 2022-06-16 DOI: 10.2427/8913

R. Saulle, S. Miccoli, B. Unim, L. Semyonov, G. Giraldi, E. Vito, M. G. Ficarra, A. Firenze, P. Gregorio, A. Boccia, G. Torre

{"title":"Validation of a questionnaire for young women to assess knowledge, attitudes and behaviors towards cervical screening and vaccination against HPV: survey among an Italian sample","authors":"R. Saulle, S. Miccoli, B. Unim, L. Semyonov, G. Giraldi, E. Vito, M. G. Ficarra, A. Firenze, P. Gregorio, A. Boccia, G. Torre","doi":"10.2427/8913","DOIUrl":"https://doi.org/10.2427/8913","url":null,"abstract":"\u0000Background: The aim of this pilot study was to assess the reliability and validity of the questionnaire in young women ≥18 years as tool to examine knowledge, attitudes and behaviors towards screening and vaccination against HPV and reliable source of information. \u0000Methods: Reliability analysis was tested and content validity was evaluated using Cronbach's alpha to check internal consistency with the intention to obtain no misunderstanding results. The questionnaire - composed by n. 3 section for a total of n. 69 items- was administered to 30 girls. The study was conducted in 4 Italian cities: Ferrara, Rome, Cassino and Palermo and data were collected in the month of October 2010. Statistical analysis was performed through SPSS 19.0, statistical software for Windows. \u0000Results: The higher value of Cronbach’s alpha resulted on 24 items (alpha= 0,774). The addition just one at time of also only one more of the others items got worse the alpha. Cronbach’s alpha on all the III section together (n. 69 items) resulted in a value of 0, 059. Young women generally known HPV can cause cervical cancer (93.3%) and genital warts (16.7%) and 76.7% of them recognize pap test as a screening tool. The main sources of information about HPV vaccination, are represented by magazines / books (33.3%), TV (26.7%), gynecologists (23.3%). \u0000Conclusion: This pilot study demonstrated that a reduced version of the questionnaire showed a very good reliability properties in the study and this needs to be taken into account for future studies. \u0000","PeriodicalId":45811,"journal":{"name":"Epidemiology Biostatistics and Public Health","volume":"91 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83983807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

New indicators of illegal drug use to compare drug user populations for policy evaluation 新的非法药物使用指标，以比较药物使用者人口，以便进行政策评价

Epidemiology Biostatistics and Public Health Pub Date : 2022-06-16 DOI: 10.2427/8891

F. Fabi, A. Mammone, C. Rossi

{"title":"New indicators of illegal drug use to compare drug user populations for policy evaluation","authors":"F. Fabi, A. Mammone, C. Rossi","doi":"10.2427/8891","DOIUrl":"https://doi.org/10.2427/8891","url":null,"abstract":"\u0000Background: New trends in drug consumption show a trend towards higher poly-use. Epidemiological indicators presently used are mostly based on the prevalence of users of the “main” substances and the ranking of harm caused by drug use is based on a single substance analysis. \u0000Methods: In this paper new indicators are proposed; the approach consider the segmentation of the population with respect to the frequency of use in the last 30 days and the harm score of the various substances used by a poly-user. Scoring is based on single substance score table reported in recent papers and principal component analysis is applied to reduce dimensionality. Any user ischaracterized by the two new scores: frequency of use score and poly-use score. \u0000Results: The method is applied to the drug user populations interviewed in Communities and Low Threshold Services within the Problem Drug Use 2012 survey in four different European countries. The comparison of the poly-use score cumulative distributions gives insight about behavioural trends of drug use and also evaluate the efficacy of the intervention services. Furthermore, the application of this method to School Population Survey 2011 data allows a definition of the expected behaviour of the poly-drug score for the General Population Survey to be representative. \u0000Conclusions: In general, the method is simply and intuitive, and could be applied to surveys containing questions about drug use. A possible limitations could be that the median is chosen for calculating the frequency of use score in questionnaires containing the frequency of drug use in classes. \u0000","PeriodicalId":45811,"journal":{"name":"Epidemiology Biostatistics and Public Health","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77595447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

The association between self-efficacy and sick-leave among men and women: a cross-sectional study of the general working population in Sweden 男性和女性的自我效能感与病假之间的关系:瑞典一般工作人口的横断面研究

Epidemiology Biostatistics and Public Health Pub Date : 2022-06-16 DOI: 10.2427/9006

K. Holmgren, A. Mårdby

{"title":"The association between self-efficacy and sick-leave among men and women: a cross-sectional study of the general working population in Sweden","authors":"K. Holmgren, A. Mårdby","doi":"10.2427/9006","DOIUrl":"https://doi.org/10.2427/9006","url":null,"abstract":"\u0000Background: The aim of this study was to investigate if low self-efficacy was associated with increased risk for sickness absence, in a general population of employed women and men. The aim was also to analyse differences in self-efficacy concerning age, education, income, and socio-economic position. \u0000Methods: This cross-sectional study was based on data collected in western Sweden, 2008. The study population consisted of 2,900 employed sick-listed individuals (E-SL) and 2,649 random working population individuals (R-WP). Both mailed questionnaire, including the General Self-Efficacy Scale (GSE) and register data on age, education, income and socio-economic position were used. A continuous mean score of the total GSE was calculated for each individual. A low GSE-score indicated low general self-efficacy. \u0000Results: Lower general self-efficacy had an increased odds ratio (OR) of belonging to a sick-listed general working population among both men (OR=1.60; 95% CI 1.32–1.94) and women (OR=1.26; 95% CI 1.08–1.47). The OR remained significant after adjustments for socio-demographic variables. Yet, men in the R-WP and women in both the R-WP and E-SL with lower education, income or socio-economic position had lower general self-efficacy compared with those in each cohort with higher education, income or socio-economic position. \u0000Conclusions: Low self-efficacy was associated with increased probability to belong to a sick-listed general working population. Although more research is needed, it seems highly relevant to take both self-efficacy and socio-economic factors into account, in preventive and rehabilitation work targeting persons on sickness absence. \u0000","PeriodicalId":45811,"journal":{"name":"Epidemiology Biostatistics and Public Health","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88571484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1