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Objective: To estimate Covid19 seropositivity among contacts of cases and to compare the seropositivity among different types of contact for assessing the differential risk & transmission dynamics.Material and Methods: A large-scale population-based serosurvey was carried out among the general population of Ahmedabad during the second half of October 2020. The contacts of cases were selected based on the population proportion and enrolled as an additional category. The seropositivity among the contacts was estimated using the enzyme-linked immunosorbent assay and compared with different types of contact and available demographic factors.Results: As of October 2020, the seropositivity against Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV2) among contacts of cases in Ahmedabad was 26.0% [95% confidence interval 24.2–28.0]. The seropositivity among family contacts was significantly higher (28.8%) compared to other contacts (24.4%) (Z=2.19, p-value=0.028). This trend was seen across all age groups and both sexes. The seropositivity was higher among females (27.7%) compared to males (24.5%) but the difference was statistically not significant (Z=1.64, p-value=0.101). In terms of age groups, the positivity had an increasing trend up to 60 years but declined after that.Conclusion: A seropositivity of 26.0% among contacts indicates that a large proportion of contacts demonstrated Immunoglobulin-G antibodies. This highlights asymptomatic transmission and/or low sensitivity of the diagnostic tests. The current strategy for contact tracing and testing among contacts is justified based on the significantly higher seropositivity among family contacts.

Background: The high fertility rate leading to the rapid growth of country’s population is a major hindrance towards the development of a nation. Sub-Saharan Africa has the highest fertility rate in the world, which is further promoted by the low utilization of contraceptive methods. Yet, many communities claim to have natural methods of family planning that pre-date the introduction of modern contraceptives, implying that contraception is a culturally acceptable norm. Objective: To Evaluate the Knowledge, Attitude and Practice towards Natural family planning among reproductive age women of Jimma town, Oromia, Ethiopia. Methods: Across sectional community based quantitative study was done in Jimma town, among reproductive age group women from February to March; 2020. A total of3 99 sample size is calculated using single population proportion formula with a proportion (P) of 50 %.Systematic random sampling technique issued to draw the study participants among the target population. The data was collected using structured questionnaire adapted from similar and the tools modified to fit the local context. The collected data was tallied and analyzed by using scientific calculator. Results: From the total of 399 respondents who responded the questionnaire Majority, 90% of women in Jimma town had a good level of knowledge of natural family planning methods. A positive attitude towards natural family planning methods was seen in (68%) of the respondents. Conclusion: A fair level of knowledge of natural family planning methods is seen among reproductive women in Jimma town, yet differences in knowledge of specific natural family planning methods exist. Therefore, physicians and other health care providers‟ limited knowledge of and experience with Natural family planning methods inhibits broader use as reproductive age women reported getting information about NFFP methods from health providers and friends, therefore, their level of knowledge will depend largely on the information received.

Background. Hypertension prevalence is continuously rising and is projected to be 1.56 billion cases by the year 2025. Despite the great progress made in the treatment of hypertension, many patients still do not achieve optimal results and experience devastating complications due to uncontrolled high blood pressure. Objective. The aim of this study is to assess self-care practice and associated factors among hypertensive patients. Methods. An institution-based cross-sectional study was conducted at Debre Tabor Referral Hospital, Northwest Ethiopia, from October to November 2020. A single population proportion formula and systematic random sampling technique was used to recruit 392 study participants. The data were entered to Epi-Info software version 7.1 and then exported to SPSS version 23 for analysis. A descriptive statistic was expressed as percentage, frequency, and mean. Finally, multivariable logistic regression was used to identify factors associated with dependent variable using a p value of

We derive the maximum likelihood estimate (MLE) of a population proportion when it differs from the same of a second population by a known value. This constrained MLE (CMLE) has a closed form in li...

COVID-19 has disproportionately affected non-Hispanic Black or African American (Black) and Hispanic persons in the United States (1,2). In North Carolina during January-September 2020, deaths from COVID-19 were 1.6 times higher among Black persons than among non-Hispanic White persons (3), and the rate of COVID-19 cases among Hispanic persons was 2.3 times higher than that among non-Hispanic persons (4). During December 14, 2020-April 6, 2021, the North Carolina Department of Health and Human Services (NCDHHS) monitored the proportion of Black and Hispanic persons* aged ≥16 years who received COVID-19 vaccinations, relative to the population proportions of these groups. On January 14, 2021, NCDHHS implemented a multipronged strategy to prioritize COVID-19 vaccinations among Black and Hispanic persons. This included mapping communities with larger population proportions of persons aged ≥65 years among these groups, increasing vaccine allocations to providers serving these communities, setting expectations that the share of vaccines administered to Black and Hispanic persons matched or exceeded population proportions, and facilitating community partnerships. From December 14, 2020-January 3, 2021 to March 29-April 6, 2021, the proportion of vaccines administered to Black persons increased from 9.2% to 18.7%, and the proportion administered to Hispanic persons increased from 3.9% to 9.9%, approaching the population proportion aged ≥16 years of these groups (22.3% and 8.0%, respectively). Vaccinating communities most affected by COVID-19 is a national priority (5). Public health officials could use U.S. Census tract-level mapping to guide vaccine allocation, promote shared accountability for equitable distribution of COVID-19 vaccines with vaccine providers through data sharing, and facilitate community partnerships to support vaccine access and promote equity in vaccine uptake.

We predict the finite population proportion of a small area when individual-level data are available from a survey and more extensive household-level (not individual-level) data (covariates but not responses) are available from a census. The census and the survey consist of the same strata and primary sampling units (PSU, or wards) that are matched, but the households are not matched. There are some common covariates at the household level in the survey and the census and these covariates are used to link the households within wards. There are also covariates at the ward level, and the wards are the same in the survey and the census. Using a two-stage procedure, we study the multinomial counts in the sampled households within the wards and a projection method to infer about the non-sampled wards. This is accommodated by a multinomial-Dirichlet–Dirichlet model, a three-stage hierarchical Bayesian model for multinomial counts, as it is necessary to account for heterogeneity among the households. The key theoretical contribution of this paper is to develop a computational algorithm to sample the joint posterior density of the multinomial-Dirichlet–Dirichlet model. Specifically, we obtain samples from the distributions of the proportions for each multinomial cell. The second key contribution is to use two projection procedures (parametric based on the nested error regression model and non-parametric based on iterative re-weighted least squares), on these proportions to link the survey to the census, thereby providing a copy of the census counts. We compare the multinomial-Dirichlet–Dirichlet (heterogeneous) model and the multinomial-Dirichlet (homogeneous) model without household effects via these two projection methods. An example of the second Nepal Living Standards Survey is presented.

The finite population proportion of a sensitive characteristic is estimated indirectly by using Randomized Response (RR) Techniques (RRT’s) pioneered by Warner (1965) followed by several other RRT’...

This paper considers the concomitant based double ranked set sampling (CDRSS) for estimating the population proportion and compares with existing concomitant based ranked set sampling (CRSS) and si...

Systematic sampling is a popular probability sampling scheme for obtaining a sample from a population having a finite size. The diagonal systematic sampling design is a type of systematic sampling scheme which has been studied by many researchers during the last 2 decades. The existing literature on the study of diagonal systematic sampling and its various forms is limited to quantitative characteristics only. This paper aims to study the estimation of finite population proportion of units which possess a particular qualitative characteristic under diagonal systematic sampling scheme. It is found that for small sample sizes, the diagonal systematic sampling scheme provides more efficient estimates of finite population proportion as compared to simple random sampling and linear systematic sampling.

Unrelated characteristics model (URL) is a type of randomized response technique (RRT) used to estimate finite population proportion of individuals bearing such a sensitive characteristic whose com...

When a survey study is related to sensitive issues such as political orientation, sexual orientation, and income, respondents may not be willing to reply truthfully, which leads to bias results. To protect the respondents’ privacy and improve their willingness to provide true answers, Warner (J Am Stat Assoc 60:63–69, 1965) proposed the randomized response (RR) technique in which respondents select a question by means of a random device in order to ensure that they maintain privacy. Huang (Stat Neerl 58:75–82, 2004) extended the RR design of Warner (1965) to propose a two-stage RR design. Not only can this method be used to estimate the population proportion of persons with a sensitive characteristic, but also estimate the honest answer rate in the first stage. This work develops a covariate extension of the two-stage RR design of Huang (2004) by applying logistic regression to investigate the effects of covariates on a sensitive characteristic and an honest response. Simulation experiments are conducted to study the finite-sample performance of the maximum likelihood estimators of the logistic regression parameters. The proposed methodology is applied to analyze the survey data of sexuality of freshmen at Feng Chia University in Taiwan in 2016.

We develop two new approximate confidence interval methods for estimating a population proportion using balanced ranked-set sampling (RSS). Unlike existing RSS-based methods, the new methods control the coverage probability well not just under perfect rankings, but also under imperfect rankings. One method uses a Wilson-type interval, and the other is based on making a mid-P adjustment to a Clopper–Pearson-type interval. Both methods rely on a new maximum-likelihood-based method for estimating the proportions in the judgment strata when the overall proportion is given, and both can be computed even for large sample sizes.

Introduction: The objectives of the present survey are to estimate the seroprevalence and sero-conversion of SARS CoV2 among the health-care workers (HCWs) in health-care establishments and to analyze the various characteristics (risk factors) associated with SARS CoV-2 infection with the overall aim to generate evidence for planning and preventive measures in the Armed Forces. Methodology: Eight hospitals have been chosen based on the hospital admission rates of COVID-19 patients and local epidemiological situation of COVID-19 prevalent in the region. A total of 3800 HCWs would be enrolled in the cross-sectional survey. For longitudinal study, 1000 personnel would be followed up at 3 and 6 months. Population proportion to size would be used for enrolment at various stages. A validation study is inbuilt in the study. From each site, a nodal officer would be designated for facilitating. Real-time data monitoring and quality checks would be done. Sero-surveillance would be done using ELISA-based immunoglobulin antibody. Results: The present study would provide the estimates of seroprevalence and rate of seroconversion among the HCWs. The factors associated with seroprevalence and seroconversion would be delineated. Discussion: The protocol lays down the plan of action to implement the multi-centric serosurveillance project. The survey will provide an assessment of seroprevalence of COVID-19 infection among the health-care workers of hospitals of central ministry from the various parts of the country and its trend over a period of time.

We propose a model-based predictive estimator of the finite population proportion of a misclassified binary response, when information on the auxiliary variable(s) is available for all units in the population. Asymptotic properties of the misclassification-adjusted predictive estimator are also explored. We propose a computationally efficient bootstrap variance estimator that exhibits better performance compared to usual analytical variance estimator. The performance of the proposed estimator is compared with other commonly used design-based estimators through extensive simulation studies. The results are supplemented by an empirical study based on literacy data.

Background Ethiopia is one of the sub-Saharan African countries with high maternal mortality and morbidity, unsafe abortion and adolescent births. Despite different policy measures taken by the government to improve sexual and reproductive health among adolescents their success is not well studied in Ethiopia. The objective of this study is to explore emergency contraceptive related knowledge, practice and its determinants among secondary school students in southern Ethiopia. Methods An institution-based cross-sectional study was conducted in selected high schools of Wolkite town, Southern Ethiopia from December to November 2019. Single population proportion formula was used to calculate sample size. A total of 327 female students participated in the study with a total response rate of 97%. Data were collected using a self-administered, structured questionnaire and cleaned, entered and analyzed using Statistical package for social science software version 21. Result 153 (54.8%) of the study participants had good knowledge about emergency contraceptives and only (40.5%) of sexually active participates used emergency contraceptives after unprotected sex. Type of admission and grade level of participants and discussion of reproductive health related issues with parents were significantly associated with good knowledge of Emergency contraceptive. Having partner and grade level of students were among the significant determinants of emergency contraceptive utilization. Conclusion The study showed an acceptable level of emergency contraceptive knowledge but only less than half of sexually active respondents used emergency contraceptives. To prevent unintended pregnancy among secondary school students sexual and reproductive health education should be given to students starting from their enrollment. Furthermore, parents should be encouraged to freely discuss sexual and reproductive health matters with their children.

New Zealand Governments have longstanding policy commitments to equal employment practices. Little attention has been paid to ethnic pay disparities in recent years. Informed by a series of official information act requests, we were interested to find out what extent, ethnic pay disparities existed within the core public sector and district health boards (DHBs). We examined the population proportions of Māori, Pasifika and Other ethnicities earning over $NZ100,000 over five year intervals between 2001 to 2016, using linear regression analysis. The analyses showed a statistically significant pattern of ethnic pay disparities across the public sector. There were fewer Māori and Pasifika staff employed in DHBs than their population proportion. The failure to promote Māori and Pasifika to the upper tiers of public sector is consistent with definitions of institutional racism. The authors call for more research to understand the dynamics of ethnic pay disparity and the drivers of this disparity.

Aim. To analyze the current state of the sanatoriums-health resorts system of the Republic of Tatarstan and identify the demand by the population of sanatoriums-health resorts services for recreation and health promotion at the regional level. Methods. To analyze the functioning of the sanatoriums-health resorts of the republic, we used data from the official website of the Federal State Statistics Service (20022018). We calculated the long-term mean values, standard deviation, growth rate, linear regression, the approximation coefficient in comparing the Republic of Tatarstan, Volga Federal District and the Russian Federation. The population proportion, which used the sanatoriums-health resorts services, bed provision per 10,000 population and bed turnover were calculated to assess the provision of the population with sanatorium-resort services. The study of the demand for sanatorium services by the population was carried out using a sociological survey. Results. In the comparative analysis, it was found that the Republic of Tatarstan is the region with a developed, relatively stable sanatoriums-health resorts system. The increase in the number of beds in sanatoriums (from 23.86 beds per 10,000 population in 2002 to 24.94 in 2018) and bed turnover rate (from 12.84 in 2002 to 16.59 in 2018) during the studied period indicated the continuity between curative and restorative-rehabilitation medicine. An increase in the proportion (from 3.07% in 2002 to 4.15% in 2018) with an overall increase in the number of stayed people (1.39 times) indicated the interest of the population in rehabilitation treatment and recreation in regional sanatoriums-health resorts. As a result of the survey, a portrait of the modern consumer of sanatoriums-health resorts was drawn up, and priorities in sanatorium choosing were determined. Conclusion. The Republic of Tatarstan belongs to the regions with a developed system of sanatoriums-health resorts and significant potential to its development, which is confirmed by the presence of natural healing factors, improved provision of sanatoriums-health resorts care and increasing demand of the population for services for rehabilitation treatment and recreation in regional sanatoriums.

Background Antenatal care (ANC) is one of the most cost-effective and crucial components of maternal health care services. In developing countries where access to care, empowerment, and decision making power of women is low, ANC service is vital. The time at which first ANC visit was done has the utmost importance to ensure optimal health effects for both women and children. This study aimed to assess the proportion and factors associated with early antenatal care booking among pregnant women who were attending public health institutions in a remote area of Bule Hora district, Southern Ethiopia, from May to July, 2019. Methods Institutional-based cross-sectional study design was conducted at Bule Hora district public health facilities. Data were collected on systematically selected 377 pregnant women from 1st May to 30th July 2019. The sample size was determined by single population proportion formula and data were collected by using a standardized and pretested questionnaire and entered into Epidata 3.1 version, and then exported to Statistical Package for Social Science (SPSS) version 25 for analysis. The strength of association was measured by odds ratios with 95% confidence interval (CI) at a p-value of

Comparing two population proportions using confidence interval could be misleading in many cases, such as the sample size being small and the test being based on normal approximation. In this case, the only one option that we have is to collect a large sample. Unfortunately, the large sample might not be possible. One example is a person suffering from a rare disease. The main purpose of this journal is to derive a closed formula for the exact distribution of the difference between two independent sample proportions, and use it to perform related inferences such as a confidence interval, regardless of the sample sizes and compare with the existing Wald, Agresti-Caffo and Score. In this journal, we have derived a closed formula for the exact distribution of the difference between two independent sample proportions. This distribution doesn’t need any requirements, and can be used to perform inferences such as: a hypothesis test for two population proportions, regardless of the nature of the distribution and the sample sizes. We claim that exact distribution has the least confidence width among Wald, Agresti-Caffo and Score, so it is suitable for inferences of the difference between the population proportion regardless of sample size.