Reducing Marketplace Interference Bias Via Shadow Prices

Marketplace companies rely heavily on experimentation when making changes to the design or operation of their platforms. The workhorse of experimentation is the randomized controlled trial (RCT), or A/B test, in which users are randomly assigned to treatment or control groups. However, marketplace interference causes the Stable Unit Treatment Value Assumption (SUTVA) to be violated, leading to bias in the standard RCT metric. In this work, we propose techniques for platforms to run standard RCTs and still obtain meaningful estimates despite the presence of marketplace interference. We specifically consider a generalized matching setting, in which the platform explicitly matches supply with demand via a linear programming algorithm. Our first proposal is for the platform to estimate the value of global treatment and global control via optimization. We prove that this approach is unbiased in the fluid limit. Our second proposal is to compare the average shadow price of the treatment and control groups rather than the total value accrued by each group. We prove that this technique corresponds to the correct first-order approximation (in a Taylor series sense) of the value function of interest even in a finite-size system. We then use this result to prove that, under reasonable assumptions, our estimator is less biased than the RCT estimator. At the heart of our result is the idea that it is relatively easy to model interference in matching-driven marketplaces since, in such markets, the platform intermediates the spillover.Comment: v3: new results on additional estimator (Two-LP), asymmetric experiments, and generalized settin

Ergonomics and Occupational Health Issues in Diagnostic Imaging: A Survey of the Situation at the Korle-Bu Teaching Hospital

The practice of Radiology requires the performance of many labour-intensive tasks relating to the delivery of quality patient care. Poor working conditions could lead to increased adverse effects on the professional which, in turn may have deleterious effects on the work performance; hence the need to ensure effective working conditions. The study sought to assess the ergonomic situation of the various imaging units at the Korle-Bu Teaching Hospital (KBTH). The subjects were final year student radiographers, qualified diagnostic Radiographers, and Radiologists at the KBTH. A quantitative research design, using a descriptive survey, was conducted as the researcher sough to obtain information about what existed with respect to the conditions within the imaging departments. A response rate of 95% was achieved.  The majority of the respondents (87.3%) lacked training on workplace ergonomics.  Additionally, there were ergonomic injuries that existed among the participants and these affected their health. The ergonomic situations at most imaging units within KBTH were not up to standard and these affect the productivity and health of the professional in the form of musculoskeletal disorders, thus requiring attention. Key words: Ergonomics, Radiographers, Radiologists, Sonographers, Musculoskeletal injurie

Influence of Parental Involvement and Academic Motivation on Mathematical Achievement: The Role of Students’ Mathematics Interest

The study examines the influence of parental involvement and academic motivation on students' mathematics performance, mediated by students' interest in mathematics. The current study adopts a descriptive-correlational research design. The study population comprises all first-year and second-year senior high students in the Central Region of Ghana. A sample of 290 students was randomly selected from four senior high schools in the Central Region of Ghana. The researcher used stratified sampling techniques to categorize the students into the various courses offered in the schools and employed simple random sampling techniques to select respondents from each stratum for the study. A structured questionnaire was used as a research instrument to collect data from the target population. Analysis of Moment Structures (Amos) version 23 and IBM SPSS version 23 were used as analysis tools for data analysis. The analysis results show that parental involvement, academic motivation, and students' interest in mathematics have a significant positive effect on mathematics achievement. Furthermore, students' interest in mathematics partially mediates the link between parental involvement and mathematics achievement. Finally, students' interest in mathematics partially mediates the connection between mathematics motivation and mathematics achievement. The study recommends that parents must be fully involved in their children's education, especially in their mathematics learning, by providing students with the necessary support to improve their mathematics learning and performance

Antenatal care attendance and low birth weight of institutional births in sub-Saharan Africa

Background: Low birth weight (LBW) remains a major health problem that affects newborns worldwide. However, there has been growing evidence that antenatal care (ANC) is associated with LBW. Yet, there is a dearth of research investigating the association between ANC attendance and LBW in sub-Saharan Africa (SSA). This study examined the association between the number of ANC visits and LBW using data from 10 sub-Saharan African countries. Methods: This study pooled data from the recent Demographic and Health Survey (DHS) of 10 sub-Saharan African countries conducted from 2018 to 2020. A total of 33,585 women aged 15–49 who had live births in the five years preceding the survey were included in this study. Bivariable and multivariable multilevel regression models were fitted to show the association between the number of ANC visits and LBW. Crude odds ratio (cOR) and adjusted odds ratio (aOR) at 95% confidence intervals (CIs) were used in presenting the results of the regression analysis. Results: The pooled prevalence of LBW was 5.7%. The highest prevalence of LBW was recorded in Gambia (7.2%) with the lowest found in Sierra Leone (2.9%). In terms of eight or more ANC visits, the overall prevalence was 14.5%. Nigeria had the highest prevalence of eight or more ANC visits (43.5%) with the lowest in Rwanda (0.2%). We found a statistically significant association between the number of ANC visits and LBW. Mothers who had eight or more ANC visits were less likely to have LBW children compared to mothers who had less than eight ANC visits [cOR = 0.66; CI = 0.55 – 0.79] and this persisted after controlling for the covariates [aOR = 0.68; CI = 0.56 – 0.82]. Covariates associated with LBW were maternal age, marital status, level of education, age of child, and wealth index. Conclusion: This study has shown a statistically significant association between ANC and LBW in SSA, with women who had eight or more ANC visits being at lower risks of giving birth to children with LBW. We found that eight or more ANC attendance was a protective factor against LBW in SSA. Therefore, it is important for sub-Saharan African countries with low prevalence of eight or more ANC attendance and high LBW prevalence to channel their efforts towards promoting more ANC attendance. © 2022, The Author(s)

Ending violence against women: Help-seeking behaviour of women exposed to intimate partner violence in sub-Saharan Africa

Introduction: Intimate partner violence is a serious public health problem that transcends cultural boundaries in sub-Saharan Africa. Studies have reported that violence characteristics and perception are strong predictors of help-seeking among women. We assessed the prevalence and factors associated with help-seeking among female survivors of intimate partner violence in sub-Saharan Africa. Methods: We pooled data from the most recent Demographic and Health Surveys (DHS) of eighteen sub-Saharan African countries. The data were extracted from the women’s files in countries with datasets from 2014 to 2021. A weighted sample of 33,837 women in sexual relationships: married or cohabiting who had ever experienced intimate partner violence within the five years preceding the survey were included in the analysis. Percentages with 95% confidence interval (CI) were used to present the results of the prevalence of help-seeking for intimate partner violence. We used a multilevel binary logistic regression analysis to examine the factors associated with help-seeking among survivors of intimate partner violence. The results were presented using adjusted odds ratio (AOR) with their respective 95% CI. Statistical significance was set at p<0.05. Results: Out of the 33,837 women who had ever experienced intimate partner violence in sub-Saharan Africa, only 38.77% (95% CI = 38.26–39.28) of them sought help. Ethiopia had the lowest prevalence of women who sought help after experiencing intimate partner violence (19.75%; 95% CI = 17.58–21.92) and Tanzania had the highest prevalence (57.56%; 95% CI = 55.86–59.26). Marital status, educational level, current working status, parity, exposure to interparental violence, women’s autonomy in household decision-making, mass media exposure, intimate partner violence justification, wealth index, and place of residence were associated with help-seeking behaviour of intimate partner violence survivors. Conclusion: The low prevalence of help seeking among women who have experienced intimate partner violence in sub-Saharan Africa calls for the intensification of formal and informal sources of assistance. Education can play a critical role in empowering girls, which may increase future help-seeking rates. Through media efforts aimed at parental awareness, the long-term benefits of females enrolling in school could be achieved. However, concentrating solely on individual measures to strengthen women’s empowerment may not bring a significant rise in help-seeking as far as patriarchal attitudes that permit violence continue to exist. Consequently, it is critical to address intimate partner violence from the dimensions of both the individual and violence-related norms and attitudes. Based on the findings, there should be public awareness creation on the consequences of intimate partner violence. Respective governments must increase their coverage of formal support services to intimate partner violence survivors especially those in rural communities

Self-reported sexually transmitted infections among adolescent girls and young women in sub-Saharan Africa

Background: Sexually transmitted infections (STIs) affect individuals of all ages, but adolescent girls and young women are disproportionately affected. We examined the prevalence and factors associated with self-reported STIs (SR-STIs) among adolescent girls and young women in sub-Saharan Africa (SSA). Methods: Demographic and Health Survey data of 27 sub-Saharan African countries were used for the study. The sample size comprised 68944 adolescent girls and young women (15–24 y of age). The outcome variable was SR-STIs. Multilevel binary logistic regression analysis was performed to identify factors associated with SR-STIs. Results: On average, the prevalence of SR-STIs among adolescent girls and young women in SSA was 6.92%. The likelihood of SR-STIs was higher among young women aged 20–24 y (adjusted odds ratio [aOR] 1.36 [confidence interval {CI} 1.27 to 1.46]), those not married (aOR 1.64 [CI 1.51 to 1.79]), those working (aOR 1.20 [CI 1.12 to 1.27]), those whose age at first sex was ≤19 y (aOR 1.99 [CI 1.80 to 2.20]), those with two or more sex partners (aOR 1.56 [CI 1.35 to 1.80]), those who listened to radio (aOR 1.26 [CI 1.17 to 1.35]), those in urban areas (aOR 1.42 [CI 1.30 to 1.51]) and those with a wealth index of rich (aOR 1.28 [CI 1.17 to 1.40]) compared with their counterparts. In contrast, those with a primary (aOR 0.86 [CI 0.78 to 0.94]) or secondary/higher level of education (aOR 0.83 [CI 0.75 to 0.92]) compared with those with no formal education and those who were exposed to television (aOR 0.90 [CI 0.84 to 0.98]) compared with those who were not exposed were less likely to report STIs. Conclusions: Our findings demonstrate the need for countries in SSA to commit towards reducing the incidence of STIs. Community-based health educational programs are required to intensify the awareness of STIs and their prevention in various sub-Saharan African countries considering the factors that expose adolescent girls and young women to STIs

Intimate partner violence against married and cohabiting women in sub-Saharan Africa: does sexual autonomy matter?

Background: Literature shows that women’s sexual autonomy, which refers to women’s capacity to refuse sex and ask a partner to use condom, has significant implications on the sexual and reproductive health outcomes and sexual-and-gender based violence. Nevertheless, there is scarcity of empirical evidence to support the association between women’s sexual autonomy and intimate partner violence (IPV) in sub-Saharan Africa. Methods: Data for the study were extracted from the recent Demographic and Health Surveys in 24 countries in sub-Saharan Africa between 2010 and 2019. Bivariable and multivariable binary logistic regression analyses were performed to examine the association between sexual autonomy and IPV in all the studied countries. Statistical significance was set at p < 0.05. Results: The pooled prevalence of IPV and sexual autonomy in the 24 countries were 38.5% and 73.0% respectively. Overall, the odds of exposure to IPV were higher among women with sexual autonomy, compared to those without sexual autonomy even after controlling for covariates (age, level of education, marital status, current working status, place of residence, wealth quintile and media exposure). At the country-level, women from Angola, Cameroon, Chad, Gabon, Cote d’lvoire, Gambia, Mali, Nigeria, Kenya, Comoros, Zambia, and South Africa who had sexual autonomy were more likely to experience IPV whilst those in Burundi were less likely to experience IPV. The study showed that sexual autonomy increases women’s exposure to IPV and this occurred in many countries except Burundi where women with sexual autonomy were less likely to experience IPV. Conclusion: The findings highlight the need for serious programs and policies to fight against IPV in the sub-region. Additionally, laws need to be passed and implemented, with law enforcement agencies provided with the necessary resources to reduce intimate partner violence among women with sexual autonomy

Assessment of knowledge, practices, and barriers to pharmacovigilance among nurses at a teaching hospital, Ghana: a cross-sectional study.

Background: Pharmacovigilance may be defined as the continuous monitoring of the reaction between a drug agent or combination of drugs a patient took and steps taken to prevent any associated risk. Clinical trials conducted before drug approval cannot uncover every aspect of the health hazards of approved drugs. People with carefully selected characteristics are monitored for the safety and efficacy of the drug; hence, common adverse drug reactions (ADRs) following proper use of the medication can be detected. This calls for continuous monitoring of drugs to report any undocumented ADRs during the clinical trial. The study aimed to assess the knowledge, practice, and barriers to pharmacovigilance among nurses at a teaching hospital. Methods: The study was a descriptive cross-sectional study, and a stratified sampling technique was used to select 125 nurses within the three units: medical, surgical, and pediatric wards. A structured questionnaire was developed and used for data collection based on the study's objectives and reviewed literature. Results: The majority (67.2%) of the respondents were females, and 32.8% were males. Most (71.2%) of the nurses had low knowledge of ADR reporting procedures. Also, 84.8% of the nurses knew the purpose of reporting ADRs. The purpose of ADR reporting, as perceived by respondents, was to identify safe drugs (80.8%) and calculate the incidence of ADR (75.2%). Additionally, among the nurses who reported having nursed a patient with ADRs, 52.54% stated they reported the case, while 47.46% did not report it. The most cited reason for not reporting ADRs was that nurses considered the reaction normal and commonly associated with that medicine (35.7%). In comparison, 28.5% of the nurses said they did not know they were supposed to report the adverse drug reaction. There was no statistically significant difference between ranks of nurses, ward, attending in-service training, and pharmacovigilance practice. Conclusion: In conclusion, nurses in this study had inadequate knowledge of pharmacovigilance and its reporting procedure. The study found that most nurses fear that reporting ADRs may be wrong because most of the nurses in the study did not have any form of pharmacovigilance training

Assessment of knowledge, practices, and barriers to pharmacovigilance among nurses at a teaching hospital, Ghana : a cross‑sectional study

Acknowledgements We would like to thank all the nurses at the various units who participated in the study. Funding The authors did not receive any specific funding for the study. The study was funded by the researchers.Peer reviewedPublisher PD

Disaster Management in High Risk Regions : A Case Study of the Indian Himalayas Region

The occurrence of several cases of natural disaster and its impact on high-risk regions remains an issue that continues to attract continued research, most especially from a global perspective. Despite the devastating impact of several known natural phenomenon such as flooding, tsunamis, earthquakes, glaciers and tornadoes, there seem not to be well-structured disaster management approach from stakeholders in high-risk disaster-prone regions to cope with eventual disaster cases. The Indian Himalayan region under review within this research article has been conducted investigated, and a review on how the build of poorly constructed residences have impacted the lives of people living within this region. This article addresses this problem in a line with well-structured thematic sections that examines community resilience, effective stakeholder communication and community preparedness can result in effective disaster management approach