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Objective: To investigate whether ovarian fragmentation for follicular activation (OFFA) improves ovarian reserve markers and in vitro fertilization (IVF) outcomes in women with poor ovarian response (POR).Design: Randomized, controlled trial, with parallel assignment.Setting: University hospital.Patient(s): Thirty-four women with POR according to the European Society of Human Reproduction and Embryology criteria.Intervention(s): Women with POR were randomly allocated to receive ovarian fragmentation in 1 ovary or to no intervention (control group). Ovarian reserve markers were followed at 2-week intervals for 6 months. In vitro fertilization cycles were initiated when the antral follicle count (AFC) doubled or at the end of follow-up.Main Outcome Measure(s): The primary outcome was the number of metaphase II (MII) oocytes obtained. Antral follicle count, antimüllerian hormone level, and reproductive outcomes were recorded as secondary outcomes. Exploratory outcomes included surgical results and analysis of protein and gene expression.Result(s): Ovarian fragmentation for follicular activation resulted in an increase in AFC in the intervention ovary compared with the control ovary and an increase in total AFC in the OFFA group compared with controls. Serum antimüllerian hormone and follicle-stimulating-hormone levels did not improve in the OFFA group throughout the follow-up period. Fifteen patients from each arm underwent IVF. In the control group, 33 MII oocytes were retrieved and 18 embryo transfers were performed, with a 20% pregnancy rate and an 18.7% live birth rate per cycle. In the OFFA group, 23 MII oocytes were retrieved and 11 embryo transfers were performed, with a 13.3% pregnancy rate and a 6.7% live birth rate per cycle. Reproductive outcomes did not significantly differ between the groups. Hippo pathway inhibition was confirmed by an 18.8% reduction in the phospho-YAP/YAP (Yes-associated protein 1) ratio and BIRC and CCN overexpression after fragmentation.Conclusion(s): Ovarian fragmentation for follicular activation in women with POR resulted in an increase in AFC but did not modify IVF outcomes when compared with controls.Clinical Trial Registration Number: NCT02354963. [ABSTRACT FROM AUTHOR]

Getting correct answers to sensitive questions from the respondents and estimating the population parameters on variables that are sensitive in nature is prevailing problem in survey sampling. In the present research paper, the problem of estimation of the population proportion of sensitive characteristics has been studied. For this, an improved randomized response device has been developed by taking the two cases of the unrelated question, case-I: 'when the proportion of unrelated characteristic is known' and other case-II: 'when the proportion of unrelated characteristic is not known'. Two estimators of the population proportion of a sensitive characteristic have been proposed, one for a known value of unrelated characteristic π y and the other for an unknown value, which were found to be unbiased. The expression for variances and unbiased estimates for the variances of the proposed estimators have been obtained. The optimum value of sample sizes has been worked out for which the minimum variance for the proposed estimators has also been obtained. An empirical study has been conducted and concluded graphically that proposed estimators are better than the estimators of Mangat (1992) and Tiwari and Mehta (2016). [ABSTRACT FROM AUTHOR]

A new randomized response technique for estimating the population total, or the population mean of a quantitative variable is proposed. It provides a high degree of protection to the respondents because they never report their data. Therefore, it may be favorably perceived by them and increase their willingness to cooperate. Instead of revealing the true value of the characteristic under investigation, the respondent only states whether the value is greater (or smaller) than a number which is selected by him/her at random and is unknown to the interviewer. For each respondent, this number, a sort of individual threshold, is generated as a pseudorandom number. Furthermore, two modifications of the proposed technique are presented. The first modification assumes that the interviewer also knows the generated random number. The second modification deals with the issue that, for certain variables, such as income, it may be embarrassing for the respondents to report either high or low values. Thus, depending on the value of the fixed threshold (unknown to the respondent), the respondent is asked different questions to avoid being embarrassed. The suggested approach is applied in detail to the simple random sampling without replacement, but it can be, after a straightforward modification, applied to many sampling schemes, including cluster sampling, two-stage sampling, or stratified sampling. The results of the simulations illustrate the behavior of the proposed technique. [ABSTRACT FROM AUTHOR]

Generally, stratification gives a small error and greater precision than the simple random sampling method in estimating the sample for the study. This paper aims to formulate the sampling problem as a multi-choice programming problem for determining the optimum allocation in the presence of non-response and considering a two-stage stratified Warner's randomized response model with cost constraint. But, mostly in real-life situations, the cost is not certain. Therefore, in cost constraint, the right-hand side parameter, i.e. total available budget, has been considered as multi-choice in nature. Multiple choices may exist for the fixed cost in the constraint, out of which exactly one has to be selected. The selection should make so that the combination of each choice should provide the best compromise optimum solution. The problem has been formulated as a multi-choice integer nonlinear programming problem, and an illustrative numerical example has been presented to demonstrate the proposed model. [ABSTRACT FROM AUTHOR]

Abstract: Large placebo responses often negatively affect randomized controlled trials within the pain area. Understanding different possible factors that influence the placebo response is therefore important. In this retrospective analysis, we hypothesized that a large variability in baseline pain score would predict a greater placebo response and analyzed the impact of the coefficient of variation, SD, and difference between the highest and lowest numeric rating scale (NRS) score at baseline on the placebo response. A total of 160 observations on placebo response from 3 controlled clinical trials with a crossover design were included in this study. In general, the placebo response was low with a mean reduction in pain intensity of 0.5 points (range -5 to 7) measured on a 0 to 10 point NRS, and only 15% were placebo responders as defined by more than 30% reduction in NRS pain score from baseline to the end of the placebo treatment period. We found no significant impact of baseline pain coefficient of variation, SD, or the difference between lowest and highest baseline pain score on the placebo response. Placebo response in one trial did not predict placebo response in another trial. A large placebo response was not associated with a large treatment response. In conclusion, in this retrospective data analysis, there was no impact of baseline pain variability on the placebo response in controlled clinical trials with a crossover design in patients with peripheral neuropathic pain. [ABSTRACT FROM AUTHOR]

Background: Eliminating hepatitis C virus (HCV) will require effective treatment delivery to persons with substance use disorders (SUDs). We evaluated the relationship between ledipasvir/sofosbuvir treatment persistence (receiving 84 tablets), adherence, and sustained virologic response (SVR) in persons with human immunodeficiency virus (HIV)/HCV coinfection.Methods: Of the 144 participants with HIV/HCV and SUDs, 110 initiated a 12-week treatment course under 1 of 3 conditions (usual care, peer mentors, and cash incentives). We used self-report, pharmacy pill counts, and expected date of refill to examine adherence. Persistent participants were categorized as high adherence (taking ≥90% of doses) or low adherence (taking <90% of doses).Results: Most participants persisted on treatment after initiation (n = 105), with 95% (n = 100) achieving SVR. One third (34%) of participants had moderate/heavy alcohol use by the biomarker phosphatidylethanol ([Peth] ≥50 ng/mL), and 44% had urine toxicology positive for cocaine or heroin at enrollment. The proportion of persons with high adherence was 72% (n = 76), and the proportion of persons with low adherence was 28%. Although low adherence was associated with moderate/heavy alcohol use by PEth (relative risk = 2.77; 95% confidence interval, 1.50-5.12), SVR did not vary according to adherence (P = .702), and most participants (97%) with low adherence achieved SVR.Conclusions: Treatment persistence led to high SVR rates among persons with HIV/HCV, despite imperfect adherence and SUDs. [ABSTRACT FROM AUTHOR]

We study the differentially private multi-group aggregation (PMGA) problem. This setting involves a single server and $n$ users. Each user belongs to one of $k$ distinct groups and holds a discrete value. The goal is to design schemes that allow the server to find the aggregate (sum) of the values in each group (with high accuracy) under communication and local differential privacy constraints. The privacy constraint guarantees that the user’s group remains private. This is motivated by applications where a user’s group can reveal sensitive information, such as his religious and political beliefs, health condition, or race. We propose a novel scheme, dubbed Query and Aggregate (Q&A) for PMGA. The novelty of Q&A is that it is an interactive aggregation scheme. In Q&A, each user is assigned a random query matrix, to which he sends the server an answer based on his group and value. We characterize the Q&A scheme’s performance in terms of accuracy (MSE), privacy, and communication. We compare Q&A to the Randomized Group (RG) scheme, which is non-interactive and adapts existing randomized response schemes to the PMGA setting. We observe that typically Q&A outperforms RG, in terms of privacy vs. utility, in the high privacy regime. [ABSTRACT FROM AUTHOR]

Prevalence of research misconduct, questionable research practices (QRPs) and their associations with a range of explanatory factors has not been studied sufficiently among academic researchers. The National Survey on Research Integrity targeted all disciplinary fields and academic ranks in the Netherlands. It included questions about engagement in fabrication, falsification and 11 QRPs over the previous three years, and 12 explanatory factor scales. We ensured strict identity protection and used the randomized response method for questions on research misconduct. 6,813 respondents completed the survey. Prevalence of fabrication was 4.3% (95% CI: 2.9, 5.7) and of falsification 4.2% (95% CI: 2.8, 5.6). Prevalence of QRPs ranged from 0.6% (95% CI: 0.5, 0.9) to 17.5% (95% CI: 16.4, 18.7) with 51.3% (95% CI: 50.1, 52.5) of respondents engaging frequently in at least one QRP. Being a PhD candidate or junior researcher increased the odds of frequently engaging in at least one QRP, as did being male. Scientific norm subscription (odds ratio (OR) 0.79; 95% CI: 0.63, 1.00) and perceived likelihood of detection by reviewers (OR 0.62, 95% CI: 0.44, 0.88) were associated with engaging in less research misconduct. Publication pressure was associated with more often engaging in one or more QRPs frequently (OR 1.22, 95% CI: 1.14, 1.30). We found higher prevalence of misconduct than earlier surveys. Our results suggest that greater emphasis on scientific norm subscription, strengthening reviewers in their role as gatekeepers of research quality and curbing the "publish or perish" incentive system promotes research integrity. [ABSTRACT FROM AUTHOR]

Surveys of income are complicated by the sensitive nature of the topic. The problem researchers face is how to encourage participants to respond and to provide truthful responses in surveys. To correct biases induced by nonresponse or underreporting, we propose a two-stage multilevel randomized response (MRR) technique to investigate the true level of income and to protect personal privacy. For a wide range of applications, we present a proportional odds model for two-stage MRR data and apply inverse probability weighting and multiple imputation methods to deal with covariates on some subjects that are missing at random. A simulation study is conducted to investigate the effects of missing covariates and to evaluate the performance of the proposed methods. The practicality of the proposed methods is illustrated with the regular monthly income data collected in the Taiwan Social Change Survey. Furthermore, we provide an estimate of personal regular monthly mean income. [ABSTRACT FROM AUTHOR]

In survey sampling an investigator may be unable to get the complete and correct information at the same time. So non-response and measurement error occur simultaneously and consequently may effect the estimator. Considering this problem, a generalized class of estimators is proposed for estimating the finite population mean for sensitive variable in the presence of measurement error and non-response under stratified random sampling. We conducted a study based on real data set at Quaid-i-Azam University, Islamabad. Simulation and real life data sets are used to observe the performances of the estimators. Bias and MSE values are given for the comparison of estimators.

Importance: Single-blind placebo run-in (PRI) periods are common in randomized clinical trials (RCTs) of treatment for depression. They aim to increase sensitivity to detect drug effects; however, the association of PRI periods with study outcomes remains unclear. This is concerning given the costs of PRI periods to patients and investigators.Objective: To examine the association of the use of PRI periods with the placebo response, drug response, and drug-placebo difference among RCTs of antidepressants.Data Sources: MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, and PsycINFO, as well as repositories of unpublished studies, were systematically searched up to July 2021.Study Selection: Included studies were double-blind, placebo-controlled RCTs of antidepressant medication among adults with depressive disorders.Data Extraction and Synthesis: Data were extracted into a coding sheet, including the characteristics of studies, the characteristics of PRI periods, and the outcomes of studies.Main Outcomes and Measures: Study outcomes were the primary depression symptom measure reported by the RCT. These outcomes were used to calculate effect sizes (Hedges g) of the within-group drug response and placebo response as well as the drug-placebo difference. Random-effects meta-analysis was used to calculate effect sizes, and subgroup analyses were used to compare outcomes depending on use of PRI periods.Results: A total of 347 trials (representing 89 183 participants) were included; 174 studies (50%) reported using a single-blind PRI period. Response outcome data were available for 189 studies. Studies using PRI periods reported a smaller placebo response (g = 1.05 [95% CI, 0.98-1.11]; I2 = 82%) than studies that did not use a PRI period (g = 1.15 [95% CI, 1.09-1.21]; I2 = 81%; P = .02). Subgroup analysis showed a larger drug response size among studies that did not use a PRI period (g = 1.55 [95% CI, 1.49-1.61]; I2 = 85%) than those that did use a PRI period (g = 1.42 [95% CI, 1.36-1.48]; I2 = 81%; P = .001). The drug-placebo difference did not differ by use of PRI periods (g = 0.33 [95% CI, 0.29-0.38]; I2 = 47% for use of a PRI period vs g = 0.34 [95% CI, 0.30-0.38]; I2 = 54% for no use of PRI periods; P = .92). The likelihood of response to drug vs placebo also did not differ between studies that used a PRI period (odds ratio, 1.89 [95% CI, 1.76-2.03]) and those that did not use a PRI period (odds ratio, 1.77 [95% CI, 1.65-1.89]; P = .18).Conclusions and Relevance: This study suggests that RCTs using PRI periods yield smaller within-group changes across both placebo and drug groups compared with RCTs without PRI periods. The reduction in effect size across groups was equivalent in magnitude. Consequently, PRI studies do not observe larger drug-placebo differences, suggesting that they do not increase trial sensitivity. As such, given the resources and probable deception required and risk to external validity, the practice of using PRI periods in RCTs of antidepressants should be ended. [ABSTRACT FROM AUTHOR]

Deceptive self-presentation on social-media platforms appears to be common. However, its prevalence and determinants are still largely unknown, partly because admitting such behavior is socially sensitive and hard to study. We investigated deceptive self-presentation from the perspective of mating theories in two key domains: physical attractiveness and personal achievement. A truth-telling technique was used to measure deceptive self-presentation in a survey of 12,257 adults (51% female) across 25 countries. As hypothesized, men and women reported more deceptive self-presentation in the domain traditionally most relevant for their gender in a mating context. However, contrary to lay beliefs (N = 790), results showed larger gender differences in deceptive self-presentation in countries with higher gender equality because there is less gender-atypical (relative to gender-typical) deceptive self-presentation in these countries. Higher gender equality was also associated with less deceptive self-presentation for men and women worldwide. [ABSTRACT FROM AUTHOR]

Randomized response (RR) designs are used to collect response data about sensitive behaviors (e.g., criminal behavior, sexual desires). The modeling of RR data is more complex since it requires a description of the RR process. For the class of generalized linear mixed models (GLMMs), the RR process can be represented by an adjusted link function, which relates the expected RR to the linear predictor for most common RR designs. The package GLMMRR includes modified link functions for four different cumulative distributions (i.e., logistic, cumulative normal, Gumbel, Cauchy) for GLMs and GLMMs, where the package lme4 facilitates ML and REML estimation. The mixed modeling framework in GLMMRR can be used to jointly analyze data collected under different designs (e.g., dual questioning, multilevel, mixed mode, repeated measurements designs, multiple-group designs). Model-fit tests, tools for residual analyses, and plot functions to give support to a profound RR data analysis are added to the well-known features of the GLM and GLMM software (package lme4). Data of Höglinger and Jann (2018) and Höglinger, Jann, and Diekmann (2014) are used to illustrate the methodology and software. [ABSTRACT FROM AUTHOR]

In sample surveys, when we need information regarding rare sensitive issues which people often do not prefer to share with others. In such situations this is also awkward for interviewers to ask the direct questions related to confidential and private matters of interviewees. An approach towards the open queries about sensitive issues generally results in the high non-response rates or misleading answers. The aim of this paper is to develop an effective randomized response model to overcome with these types of challenges arising due to sensitive nature of characteristic under study. In this paper we have proposed three-stage randomized response model for estimating mean number of individuals who possessed rare sensitive attribute which makes use of Poisson distribution. The properties of the proposed estimation procedures have been deeply examined when the parameter of a rare unrelated attribute is known as well as unknown. Privacy protection of respondents is also an equally important matter of concern. So measure of privacy protection for the proposed randomized response model has also been examined. Empirical studies are performed to support the theoretical results, which show the dominance of the proposed estimators over well-known contemporary estimators. From the findings of this study we may conclude that proposed randomized response model is rewarding in terms of percent relative efficiencies and privacy protection and may be recommended to survey practitioners for real life applications. [ABSTRACT FROM AUTHOR]

We investigate the association of a sensitive characteristic or latent variable with observed binary random variables by the randomized response (RR) technique of Warner in his publication (Warner, S.L. J. Am. Stat. Assoc.1965, 60, 63–69) and a latent class model. First, an expectation-maximization (EM) algorithm is provided to easily estimate the parameters of the null and alternative/full models for the association between a sensitive characteristic and an observed categorical random variable under the RR design of Warner’s paper above. The likelihood ratio test (LRT) is utilized to identify observed categorical random variables that are significantly related to the sensitive trait. Another EM algorithm is then presented to estimate the parameters of a latent class model constructed through the sensitive attribute and the observed binary random variables that are obtained from dichotomizing observed categorical random variables selected from the above LRT. Finally, two classification criteria are conducted to predict an individual in the sensitive or non-sensitive group. The practicality of the proposed methodology is illustrated with an actual data set from a survey study of the sexuality of first-year students, except international students, at Feng Chia University in Taiwan in 2016.

In recent years, marketing researchers have become increasingly interested in under- and overreporting. However, there are few suitable approaches to operationalize deviations from the truth, particularly in behavioral domains in which self-reports are usually the only viable method of choice to measure behavior or attitudes. An especially difficult situation arises if some people underreport while others overreport. This article proposes a Bayesian item response theory model to quantify under- and overreporting in surveys. The method utilizes within-person differences between answers obtained under direct questioning (no privacy protection) and randomized-response questioning (which ensures item-level privacy protection). This method has the important features of incorporating behavioral response-mode effects (e.g., privacy loss when switching from direct to randomized-response questioning, response-mode inertia effects) and allowing the direction of bias to differ across respondents. The authors provide an empirical application for excessive alcohol consumption involving 1,408 respondents from a commercial web panel. The results show that respondents are averse to decreases in privacy and that randomized response is less effective if respondents provide biased responses to earlier direct questions. [ABSTRACT FROM AUTHOR]

Introduction: ND0612 is a continuous, subcutaneous levodopa/carbidopa delivery system under development for patients with Parkinson's disease (PD) and motor fluctuations.Methods: This was a randomized, placebo-controlled, double-blind, 2-period study evaluating the safety and pharmacokinetics of ND0612 in PD patients on an optimized oral levodopa regimen and experiencing ≥2 h/day of OFF time. During Period-1, patients received their current standard of care (SoC) levodopa/carbidopa and were randomized (2:1) to 14 days treatment with adjunct ND0612 (daily levodopa/carbidopa dose of 270/63 mg) or placebo infusion +SoC. During Period-2, 16 patients were randomized to receive 7 days treatment with ND0612 or ND0612 plus oral entacapone. Reduction in OFF time was analyzed as an exploratory measure using a futility design with a predefined margin of 1.6 h.Results: ND0612 was well-tolerated; most patients experienced infusion site nodules (95% vs. 56% with placebo), which all resolved without sequelae. Patients treated with adjunct ND0612 during Period-1 avoided deep troughs in levodopa plasma levels and had a decreased fluctuation index versus placebo (1.6 ± 0.5 vs 3.1 ± 1.6 at end of Period-1, respectively). In Period-2, the coadministration of entacapone with continuous ND0612 SC infusion translated to an increase in mean levodopa AUC0-10h compared to baseline. Exploratory efficacy analysis of Period 1 showed mean ± SD OFF time reductions of -2.13 ± 2.24 [90%CI: -2.8, ∞] hours (p = 0.84 using H0 of μ0 ≤-1.6).Conclusion: Levodopa/carbidopa infusion with ND0612 was generally well-tolerated and resulted in reduced fluctuations in plasma levodopa concentrations when given with SoC oral levodopa. ND0612 met the efficacy endpoint for the futility design. [ABSTRACT FROM AUTHOR]

The illegal use of natural resources, manifested in activities like illegal logging, poaching, and illegal wildlife trade, poses a global threat to biodiversity. Addressing them will require an understanding of the magnitude of and factors influencing these activities. However, assessing such behaviors is challenging because of their illegal nature, making participants less willing to admit engaging in them. We compared how indirect (randomized response technique) and direct questioning techniques performed when assessing non‐sensitive (fish consumption, used as negative control) and sensitive (illegal consumption of wild animals) behaviors across an urban gradient (small towns, large towns, and the large city of Manaus) in the Brazilian Amazon. We conducted 1,366 surveys of randomly selected households to assess the magnitude of consumption of meat from wild animals (i.e., wild meat) and its socioeconomic drivers, which included years the head of household lived in urban areas, age of the head of household, household size, presence of children, and poverty. The indirect method revealed higher rates of wildlife consumption in larger towns than did the direct method. Results for small towns were similar between the two methods. The indirect method also revealed socioeconomic factors influencing wild meat consumption that were not detected with direct methods. For instance, the indirect method showed that wild meat consumption increased with age of the head of household, and decreased with poverty and years the head of household lived in urban areas. Simultaneously, when responding to direct questioning, households with characteristics associated with higher wild meat consumption, as estimated from indirect questioning, tended to underreport consumption to a larger degree than households with lower wild meat consumption. Results for fish consumption, used as negative control, were similar for both methods. Our findings suggest that people edit their answers to varying degrees when responding to direct questioning, potentially biasing conclusions, and indirect methods can improve researchers' ability to identify patterns of illegal activities when the sensitivity of such activities varies across spatial (e.g., urban gradient) or social (e.g., as a function of age) contexts. This work is broadly applicable to other geographical regions and disciplines that deal with sensitive human behaviors. [ABSTRACT FROM AUTHOR]

Surveying human behaviors, especially in demographic, social, medical and public health research, often involves sensitive issues. Posing direct inquiries about stigmatizing or threatening topics may lead survey participants to refuse to answer or to give untruthful responses. Nonresponse and misreporting denote measurement errors that are difficult to treat and are likely to yield unreliable analyses of the surveyed topics. This problem can be mitigated by adopting survey methods that enhance anonymity and respondent cooperation. One possibility is to create a trustful and confidential relationship between the interviewer and the survey participants. Alternatively, it is possible to fully protect privacy by adopting indirect questioning procedures that elicit information without posing sensitive questions directly. We consider both above-mentioned possibilities showing the results of a real study which explores the effectiveness of the randomized response crossed model proposed by Lee et al. (2013) to produce prevalence estimates for two sensitive traits, cannabis use and its legalization. [ABSTRACT FROM AUTHOR]

The randomized response technique (RRT) is an effective method designed to obtain the sensitive information from respondents while assuring the privacy. Narjis and Shabbir [Narjis, G., and J. Shabbir. 2018. Estimation of population proportion and sensitivity level using optional unrelated question randomized response techniques. Communications in Statistics – Simulation and Computation 0 (0):1–15] proposed three binary optional unrelated question RRT models for estimating the proportion of population that possess a sensitive characteristic (π) and the sensitivity level (ω) of the question. In this study, we have developed the Bayes estimators of two parameters (π , ω) for optional unrelated question RRT model along with their corresponding minimal Bayes posterior expected losses (BPEL) under squared error loss function (SELF) using beta prior. Relative losses, mean squared error (MSE) and absolute bias are also examined to compare the performances of the Bayes estimates with those of the classical estimates obtained by Narjis and Shabbir (2018). A real survey data are provided for practical utilizations. [ABSTRACT FROM AUTHOR]

The study is investigated on an alternative method for the construction of strata using sensitivity level when the samples are selected with simple random sampling with replacement (SRSWR) and the data are collected by scrambled optional randomization technique on the sensitive characters. Thus, the optional randomized response model Z=Y.Sk, where k is a random variable having value 1 if the response is scrambled and 0 otherwise, was considered for finding out Approximate Optimum Strata Boundaries by minimizing the variance of the estimator ̄yst. The cum. ... was proposed for finding out Approximate Optimum Strata Boundary in Neyman allocation for the optional scrambled response. This is applicable for wider classes of sampling design and estimators in stratification. The proposed rule on optional scrambled randomized response is efficient and can be used effectively for the construction of optimum strata boundary via Rectangular, Right triangular and Exponential distribution. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Deep learning models are widely being used to provide relevant recommendations in hybrid recommender systems. These hybrid systems combine the advantages of both content based and collaborative filtering approaches. However, these learning systems hamper the user privacy and disclose sensitive information. This paper proposes a privacy preserving deep learning based hybrid recommender system. In hybrid deep neural network, user's side information such as age, location, occupation, zip code along with user rating is embedded and provided as input. These embedding's pose a severe threat to individual privacy. In order to eliminate this breach of privacy, we have proposed a private embedding scheme that protects user privacy while ensuring that the nonlinear latent factors are also learnt. In this paper, we address the privacy in hybrid system using differential privacy, a rigorous mathematical privacy mechanism in statistical and machine learning systems. In the reduced feature set, the proposed adaptive perturbation mechanism is used to achieve higher accuracy. The performance is evaluated using three datasets with root mean square error (RMSE), mean absolute error (MAE), mean squared error (MSE), R squared, precision and recall. These evaluation metrics are compared with varying values of privacy parameter ϵ. The experimental results show that the proposed solution provides high user privacy with reasonable accuracy than the existing system. As the engine is generic, it can be used on any recommendation framework. [ABSTRACT FROM AUTHOR]

This study proposes optional Randomized Response Technique (RRT) models in a binary response situation. The application of the proposed optional RRT models under stratifcation is also explored. Gupta et al. [1] introduced an ingenious idea of optional RRT model in which a question may appear sensitive to one respondent while being not sensitive to another. This study focuses on estimating the prevalence of sensitive attribute, π, the sensitivity level of the underlying sensitive question when the proportion of unrelated innocuous attribute is unknown. A new multi-question approach is proposed for estimation of parameters (π). A comparison between the proposed optional RRT models and the corresponding full RRT models is carried out numerically under simple and stratified random sampling. [ABSTRACT FROM AUTHOR]

This document is a response to a comment on a randomized clinical trial comparing two surgical techniques for gastrectomy in cancer patients. The authors provide evidence for the effectiveness of D2 lymphadenectomy plus complete mesogastric excision (CME) in reducing surgical risk and improving oncological outcomes. They address concerns about surgeon proficiency, potential bias in the study, and the role of neoadjuvant chemotherapy. The authors conclude that D2 + CME shows potential benefits but acknowledge the need for further evaluation, particularly in patients receiving neoadjuvant chemotherapy. [Extracted from the article]

For the study of privacy-utility trade-off in local differential privacy,the utility optimization models of binary generalized random response mechanism for the case of differential privacy and approximate differential privacy were established.By graphic method,optimality proof,software solution and extreme point method,the exact expression of the optimal utility with privacy budget and the distribution of input data was obtained,and the corresponding optimal randomized response mechanism was given.The results show that both the optimal utility and optimal mechanism are related to privacy budget and input data distribution.Moreover,the discussion for multivariate randomized response mechanism shows that the method of extreme points of local differential privacy is feasible to the solution.

Tools for reliable assessment of socially sensitive or transgressive behavior warrant constant development. Among them, the Crosswise Model (CM) has gained considerable attention. We systematically reviewed and meta-analyzed empirical applications of CM and addressed a gap for quality assessment of indirect estimation models. Guided by the PRISMA protocol, we identified 45 empirical studies from electronic database and reference searches. Thirty of these were comparative validation studies (CVS) comparing CM and direct question (DQ) estimates. Six prevalence studies exclusively used CM. One was a qualitative study. Behavior investigated were substance use and misuse (k = 13), academic misconduct (k = 8), and corruption, tax evasion, and theft (k = 7) among others. Majority of studies (k = 39) applied the “more is better” hypothesis. Thirty-five studies relied on birthday distribution and 22 of these used P = 0.25 for the non-sensitive item. Overall, 11 studies were assessed as high-, 31 as moderate-, and two as low quality (excluding the qualitative study). The effect of non-compliance was assessed in eight studies. From mixed CVS results, the meta-analysis indicates that CM outperforms DQ on the “more is better” validation criterion, and increasingly so with higher behavior sensitivity. However, little difference was observed between DQ and CM estimates for items with DQ prevalence estimate around 50%. Based on empirical evidence available to date, our study provides support for the superiority of CM to DQ in assessing sensitive/transgressive behavior. Despite some limitations, CM is a valuable and promising tool for population level investigation.

Background: Contextual effects (i.e., placebo response) refer to all health changes resulting from administering an apparently inactive treatment. In a randomized clinical trial (RCT), the overall treatment effect (i.e., the post-treatment effect in the intervention group) can be regarded as the true effect of the intervention plus the impact of contextual effects. This meta-research was conducted to examine the average proportion of the overall treatment effect attributable to contextual effects in RCTs across clinical conditions and treatments and explore whether it varies with trial contextual factors.Methods: Data was extracted from trials included in the main meta-analysis from the latest update of the Cochrane review on "Placebo interventions for all clinical conditions" (searched from 1966 to March 2008). Only RCTs reported in English having an experimental intervention group, a placebo comparator group, and a no-treatment control group were eligible.Results: In total, 186 trials (16,655 patients) were included. On average, 54% (0.54, 95%CI 0.46 to 0.64) of the overall treatment effect was attributable to contextual effects. The contextual effects were higher for trials with blinded outcome assessor and concealed allocation. The contextual effects appeared to increase proportional to the placebo effect, lower mean age, and proportion of females.Conclusion: Approximately half of the overall treatment effect in RCTs seems attributable to contextual effects rather than to the specific effect of treatments. As the study did not include all important contextual factors (e.g., patient-provider interaction), the true proportion of contextual effects could differ from the study's results. However, contextual effects should be considered when assessing treatment effects in clinical practice.Trial Registration: PROSPERO CRD42019130257 . Registered on April 19, 2019. [ABSTRACT FROM AUTHOR]

We proposed a generalized two stage optional randomized response model by single sample approach and developed a generalized exponential type estimator for the mean of sensitive variable using information from a non-sensitive auxiliary variable. Privacy protection and some special cases for the suggested model has also been discussed. Simulation and numerical study are carried out to assess the performance of the suggested estimator. We compare the proposed model with some existing estimators and conclude that our proposed model is more efficient under certain conditions. [ABSTRACT FROM AUTHOR]

Purpose: This study compared the therapeutic effects of transdermal testosterone gel (TTG) application at 4 and 6 weeks before controlled ovarian hyperstimulation (COH) in women with poor ovarian response (POR). Methods: In this randomized control trial, infertile women with POR who underwent in vitro fertilization (IVF) were recruited and randomly classified into 4 week (n = 42) and 6 week (n = 38) TTG treatment groups and control group (n = 42). The primary outcome was total number of retrieved mature oocytes. The secondary outcomes were the biochemical pregnancy rate, clinical pregnancy rate, and ongoing pregnancy rate. Results: No significant differences were observed in the number of oocytes retrieved, mature oocytes and embryos between all groups. Human chorionic gonadotropin (hCG) positive, clinical, and ongoing pregnancy rates were significantly higher in the TTG pretreatment groups than in the control group but no differences were observed between the 4‐ and 6 week groups. Conclusions: Applying TTG in infertile women with POR may ameliorate the outcomes of IVF. The extended application of TTG to 6 weeks did not improve the response to ovarian stimulation regarding the number of retrieved oocytes nor pregnancy outcomes compared to the 4 week pretreatment. [ABSTRACT FROM AUTHOR]

Previous studies have identified catechol-O-methyltransferase (COMT), as a key enzyme influencing sympathetic function. Although the COMT SNP rs4680 and rs4818, are well-studied, little is known about their influence on cancer-related fatigue (CrF) and placebo response. In this study, we examined whether genetic variation in COMT , at the functional SNP rs4680 and linked rs4818, influenced open-label placebo (OLP) responses found in cancer survivors reporting moderate to severe CrF. We randomized cancer survivors (N = 74) reporting moderate-to-severe CrF to receive OLP or to treatment-as-usual (TAU) and assessed if rs4680 and rs4818 were associated with changes in fatigue severity and fatigue-distressed quality of life. At the end of the initial 21 days, the treatments were crossed over and both groups were re-assessed. Participants with the rs4680 high-activity G-allele (G/G or G/A) or rs4818 C/G genotypes reported significant decreases in fatigue severity and improvements in fatigue-distressed quality of life. The COMT rs4818 findings replicated findings in a similar study of OLP in cancer fatigue. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT02522988. [ABSTRACT FROM AUTHOR]

Tools for reliable assessment of socially sensitive or transgressive behavior warrant constant development. Among them, the Crosswise Model (CM) has gained considerable attention. We systematically reviewed and meta-analyzed empirical applications of CM and addressed a gap for quality assessment of indirect estimation models. Guided by the PRISMA protocol, we identified 45 empirical studies from electronic database and reference searches. Thirty of these were comparative validation studies (CVS) comparing CM and direct question (DQ) estimates. Six prevalence studies exclusively used CM. One was a qualitative study. Behavior investigated were substance use and misuse (k = 13), academic misconduct (k = 8), and corruption, tax evasion, and theft (k = 7) among others. Majority of studies (k = 39) applied the "more is better" hypothesis. Thirty-five studies relied on birthday distribution and 22 of these used P = 0.25 for the non-sensitive item. Overall, 11 studies were assessed as high-, 31 as moderate-, and two as low quality (excluding the qualitative study). The effect of non-compliance was assessed in eight studies. From mixed CVS results, the meta-analysis indicates that CM outperforms DQ on the "more is better" validation criterion, and increasingly so with higher behavior sensitivity. However, little difference was observed between DQ and CM estimates for items with DQ prevalence estimate around 50%. Based on empirical evidence available to date, our study provides support for the superiority of CM to DQ in assessing sensitive/transgressive behavior. Despite some limitations, CM is a valuable and promising tool for population level investigation. [ABSTRACT FROM AUTHOR]

In this study we propose an improved mean estimator for a sensitive variable under simple random sampling using Optional RRT models when measurement errors are present. We discuss two scrambling options and compare the mean square error (MSE) of the proposed estimator with some of the commonly used estimators. Both theoretical and empirical results show the superiority of the proposed estimator over existing estimators. Models are evaluated both with respect to efficiency and respondent privacy. [ABSTRACT FROM AUTHOR]

Introduction: In biometric sample surveys, our objective is to get ready-made information for future planning and policy implementations related to the subject matters of highly sensitive issues. In such situations, we apply randomized response/scrambled response techniques. There are many highly sensitive issues which need to be examined over time as they may have a tendency to change. To get rid of these types of practical cases we need a scrambled response technique on successive occasions. Methods: Using an additive and multiplicative technique, we proposed new effective scrambled response models to estimate the population mean of quantitative sensitive characteristics. Degree of privacy protection and unified measure approaches are used to examine the efficacy of the proposed models. Efficiency of the proposed models has been checked using MATLAB software. The utility of the proposed models under two occasions of successive sampling has been also explored using exponential-type estimators. Empirical and simulation studies are carried out to justify the proposition of the proposed estimators using MATLAB software. Results: The percent relative efficiencies of the proposed models are always greater than 100 with respect to the well-known Bar-Lev et al model. In terms of degree of privacy protection, most of the values are greater than 0.5 and closer to 1. Similarly, the values of the proposed models are smaller with respect to the Bar-Lev et al model in terms of a unified measure approach. When the proposed scrambled response models are used on successive occasions, the percent relative efficiency is always found greater than 100 for all cases over its competitors. Discussion: In this study, after deeply examining the properties of the proposed models, we found that the proposed models performed better over the well-known existing model. The proposed models may be used in human survey when we deal with highly sensitive issues. The proposed models also performed better when we utilized them in successive sampling. Hence, if sensitive characteristics change with time, the proposed estimators may be the best alternative to deal with these types of situations. Mathematics Subject Classification: 62D05. [ABSTRACT FROM AUTHOR]

This paper suggests a new randomized response model useful for gathering information on quantitative sensitive variable such as drug usage, tax evasion and induced abortions etc. The resultant estimator has been found to more efficient than the estimator of the Saha (2007) under some realistic conditions. We have illustrated results numerically. [ABSTRACT FROM AUTHOR]

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In surveys, proportions of individuals self-reporting as bisexual and homosexual are likely to suffer from misreports or refusal to answer when directly questioned. For more reliable information, the randomized response technique is often used. Therefore, to reduce social desirability bias, a multi-level randomized response technique has been used in Taiwan to collect self-reported sexual identity. Using the Taiwan Social Change Survey as a case study, we estimate proportions of individuals aged 18–54 years self-reporting as bisexual and homosexual. Empirical results show individual determinants of truthful response differ across data collection modes and estimation methods. Moreover, estimated proportions of non-heterosexuals in small samples obtained by the maximum likelihood method are less meaningful and accurate than Bayes ones. [ABSTRACT FROM AUTHOR]

In recent decades, the randomized response technique has attracted researchers due to its usefulness in sensitive surveys. The randomized response procedure is used for the collection of responses on sensitive issues such as cheating in examination, income earned through illegal sources, expenditure on luxury items, and amount of tax paid, etc. This study introduces a new variant of quantitative randomized response models for use with sample surveys where the variable of interest is quantitative. The properties of a mean estimator based on the new technique have been studied. Further, the combined and separate evaluation metrics for efficiency and privacy level have also been derived and compared with those of the existing methods. Further, a simulation study has been conducted to prove the improvement in the degree of privacy protection and efficiency. The findings reveal that the suggested randomized response technique is not only more efficient than the existing techniques, but also improves the joint measure of efficiency and respondents' privacy, making it preferable over the existing techniques. A real-world example of a sample survey through the suggested model is also presented which illustrates its usefulness in practical surveys on sensitive issues., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Privacy security issues under the classic randomized response (RR) model proposed by Warner and its extended K-RR model are studied. First, in order to provide references for the accuracy of the private distribution estimation problem under RR mechanism, the lower bounds of the differential privacy parameter and the number of participates are deduced for an accuracy objective of (α, δ)-accurate in statistics. Second, when the prior distribution is nonuniform, the data utility has a ceiling effect in the high privacy region by taking the prior into account. In this case, the average distortion, which is defined as the expected Hamming distance between the input and output data, is no longer feasible to measure the data utility. Motivated by this, the error probability is proposed as a measure of data utility for unifying different privacy metrics, where the error probability is defined to be the expected Hamming distance between the input and reconstructed data based on maximum a posteriori estimation. Third, under a unified privacy-preserving framework using RR mechanism based on error probability criterion, the relationship among differential privacy, identifiability privacy, and mutual information privacy is established. Given a maximum allowable error probability PEmax, the optimal privacy parameters of these three privacy notions are derived with the full consideration of the prior distribution. Then, a Bayes-based utility function, which corresponds to the converse of the Bayes risk, is constructed to measure the degree of privacy leakage. Given a maximum allowable correct probability PCmax, the accuracy objective of the statistical estimate is considered to derive the range of local differential privacy parameter from the perspective of security. Fourth, all the research results above are further extended to K-RR mechanism too. Finally, the correctness and effectiveness are further verified by simulation experiments. The results reveal that the error probability can be applied to any prior distribution case, while the average distortion criterion is only a special case with uniform distribution. Therefore, the error probability proposed in the paper is more reasonable to be used as a common criterion to measure the data utility for the RR model so as to unify different privacy metrics.

The randomized response (RR) technique was developed to improve the validity of measures assessing attitudes, behaviors, and attributes threatened by social desirability bias. The RR removes any direct link between individual responses and the sensitive attribute to maximize the anonymity of respondents and, in turn, to elicit more honest responding. Since multivariate analyses are no longer feasible using standard methods, we present the R package RRreg that allows for multivariate analyses of RR data in a user-friendly way. We show how to compute bivariate correlations, how to predict an RR variable in an adapted logistic regression framework (with or without random effects), and how to use RR predictors in a modified linear regression. In addition, the package allows for power analysis and robustness simulations. To facilitate the application of these methods, we illustrate the benefits of multivariate methods for RR variables using an empirical example.

Background: Neoadjuvant chemotherapy (NACT) is the prime approach to the management of locally advanced breast cancer (LABC). Influenced by different factors such as pathologic tumor characteristics, hormone receptor status, HER2 and proliferation marker expressions, response to therapy cannot be easily predicted. Pathologic complete response (pCR) has been considered as an endpoint to NACT; however, pCR rates have been unsatisfactory in such patients. In this randomized trial, we studied the efficacy of carboplatin/gemcitabine as second-line NACT while evaluating the impact of different factors affecting response.Methods: In this randomized controlled trial, 52 clinically non-responsive (confirmed by palpation and/or ultrasonography) LABC patients to 4 cycles of doxorubicin/cyclophosphamide followed by 4 cycles of paclitaxel ± trastuzumab were randomly allocated to two groups. "Control" group underwent breast surgery and were further evaluated for pCR (ypT0/is ypN0). "Intervention" group received 2 cycles of carboplatin/gemcitabine and patients were further evaluated for pCR following surgery.Results: In a total of 52 patients, pCR rate was 30.7%. pCR and response rate in lymph nodes were higher in carboplatin/gemcitabine recipients (32% vs 29.7 and 44% vs 40.7% respectively), however differences were insignificant. In both the "intervention" group and total study population, most pCR cases were of the hormone receptor (HR)+/HER2+ subtype (87.5% and 75% respectively). HER2 positivity, ki67 expression, lower extent of ER positivity, higher tumor grade and tumor-infiltrating lymphocyte (TIL) lead to higher pCR rates. Adverse events following addition of carboplatin/gemcitabine were mostly hematologic and none required hospitalization. Anemia was the most common grade 3 adverse event observed. No grade 4 toxicity was evident.Conclusion: Although the proposed carboplatin/gemcitabine combination could not improve pCR rates as expected, probability of immune activation following use of carboplatin in achieving response to NACT may be considered. Accounting for the highest number of pCR cases in the "intervention" group, the HR+/HER2+ subtype with high TILs may be considered as most responsive to the proposed regimen in this study. It is noteworthy that the proposed combination imposed minimal toxicity.Trial Registration: This trial was prospectively registered in IRCT.ir ( IRCT2017100136491N1 ). Date of registration: 19 November 2017. [ABSTRACT FROM AUTHOR]

We consider a setup in which condential i.i.d. samples X1; Xn from an unknown nite-support distribution p are passed through n copies of a discrete privatization channel (a.k.a. mechanism) producing outputs Y1;: ::; Yn. The channel law guarantees a local dierential privacy of ffl. Subject to a prescribed privacy level ffl, the optimal channel should be designed such that an estimate of the source distribution based on the channel outputs Y1;: ::; Yn converges as fast as possible to the exact value p. For this purpose we study the convergence to zero of three distribution distance metrics: f-divergence, meansquared error and total variation. We derive the respective normalized rst-order terms of convergence (as n ! 1), which for a given target privacy ffl represent a rule-of-thumb factor by which the sample size must be augmented so as to achieve the same estimation accuracy as that of a non-randomizing channel. We formulate the privacy-delity trade-o problem as being that of minimizing said rst-order term under a privacy constraint ffl. We further identify a scalar quantity that captures the essence of this trade-o, and prove bounds and data-processing inequalities on this quantity. For some specic instances of the privacy-delity trade-o problem, we derive inner and outer bounds on the optimal trade-o curve. [ABSTRACT FROM AUTHOR]

The operating characteristics (OCs) of a subset ranking and selection procedure are derived for a randomized response model for continuous data. In this article the operating characteristics for the subset selection procedure are considered for two parameter configurations, the slippage configuration and the equi-spaced configuration, and tables are provided for each case for some specific choices of problems parameters. [ABSTRACT FROM AUTHOR]