Gates Open Research最新文献

{"title":"Developing a framework for understanding policy decision-making behaviors in the transition of an HIV prevention program towards sustainability: a case study from Zambia's voluntary medical male circumcision program.","authors":"Nishan Gantayat, James Baer, Alok Gangaramany, Steve Kretschmer, Rasi Surana, Alick Samona, Njekwa Mukamba, Bright Jere, Tina Chinsenga, Ram Prasad, Stephen Goetschius, Saransh Sharma","doi":"10.12688/gatesopenres.15189.2","DOIUrl":"10.12688/gatesopenres.15189.2","url":null,"abstract":"<p><p>Faced with declining donor funding for HIV, low- and middle-income countries must identify efficient and cost-effective ways to integrate HIV prevention programs into public health systems for long-term sustainability. In Zambia, donor support to the voluntary medical male circumcision (VMMC) program, which previously funded non-governmental organizations as implementing partners, is increasingly being directed through government structures instead. We developed a framework to understand how the behaviors of individual decision-makers within the government could be barriers to this transition. We interviewed key stakeholders from the national, provincial, and district levels of the Ministry of Health, and from donors and partners funding and implementing Zambia's VMMC program, exploring the decisions required to attain a sustainable VMMC program and the behavioral dynamics involved at personal and institutional levels. Using pattern identification and theme matching to analyze the content of the responses, we derived three core decision-making phases in the transition to a sustainable VMMC program: 1) developing an alternative funding strategy, 2) developing a policy for early-infant (0-2 months) and early-adolescent (15-17 years) male circumcision, which is crucial to sustainable HIV prevention; and 3) identifying integrated and efficient implementation models. We formulated a framework showing how, in each phase, a range of behavioral dynamics can form barriers that hinder effective decision-making among stakeholders at the same level (e.g., national ministries and donors) or across levels (e.g., national, provincial and district). Our research methodology and the resulting framework offer a systematic approach for in-depth investigations into organizational decision-making in public health programs, as well as development programs beyond VMMC and HIV prevention. It provides the insights necessary to map organizational development and policy-making transition plans to sustainability, by explaining tangible factors such as organizational processes and systems, as well as intangibles such as the behaviors of policymakers and institutional actors.</p>","PeriodicalId":12593,"journal":{"name":"Gates Open Research","volume":"8 ","pages":"18"},"PeriodicalIF":0.0,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11421490/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142344903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Knowledge and uptake of contraceptive and other sexual reproductive health services among in-school adolescents in three South African townships: Baseline findings from the Girls Achieve Power (GAP Year) Trial.","authors":"Melanie Pleaner, Alison Kutywayo, Mags Beksinska, Khuthala Mabetha, Nicolette Naidoo, Saiqa Mullick","doi":"10.12688/gatesopenres.13636.2","DOIUrl":"10.12688/gatesopenres.13636.2","url":null,"abstract":"<p><strong>Background: </strong>South African adolescents experience barriers to sexual and reproductive health (SRH) knowledge and uptake. This study provides insight into contraceptive and other SRH service knowledge, perceptions, and uptake among adolescents in high HIV prevalence settings.</p><p><strong>Methods: </strong>A baseline cross sectional survey was conducted among 3432 grade 8s enrolled into the Girls Achieve Power (GAP Year) trial from 26 public high schools across three South African townships (Soweto, Thembisa and Khayelitsha) (2017 - 2018). An interviewer-led survey collected information on SRH knowledge and perceptions; an audio computer-assisted self-interviewing technique gathered SRH service uptake. Descriptive analysis indicates frequency distribution of socio-demographics and knowledge, uptake and perceptions of SRH services. Chi-square test tested for associations between age and sex and selected variables that measure SRH knowledge and uptake.</p><p><strong>Results: </strong>In total, 2383 participants completed both survey components. Of these, 63.1% (n=1504) were female and 81.4% (n=1938) aged 12-14. Almost a fifth (18.3%, n=436) had ever had sex and less than 1% had accessed SRH services in the last year. Of the 157 females who had ever had sex, 50.9% had ever used contraception. Of those who had sex in the last three months, 59.0% reported using a contraceptive method. Condom use was inconsistent: almost all females said they had not used or could not remember if a condom was used at last sex.</p><p><strong>Conclusion: </strong>This paper contributes to the evidence strengthening learner SRH education, including the national Integrated School Health Programme. Key themes include the need for age-appropriate, differentiated comprehensive sexuality education (CSE) for the range of ages found in the same grade in South African schools. Education on different contraceptive methods, informed decision-making, and emergency contraception is key. School-based interventions should embrace integrated HIV, STI, and pregnancy prevention messages. Closer links with health services need to be constantly fostered and reinforced.</p>","PeriodicalId":12593,"journal":{"name":"Gates Open Research","volume":"6 ","pages":"67"},"PeriodicalIF":0.0,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10213203/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9546461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using models and maps to inform Target Product Profiles and Preferred Product Characteristics: the example of <i>Wolbachia</i> replacement.","authors":"Katie Tiley, Julian Entwistle, Bruce Thomas, Laith Yakob, Oliver Brady","doi":"10.12688/gatesopenres.14300.3","DOIUrl":"https://doi.org/10.12688/gatesopenres.14300.3","url":null,"abstract":"<p><strong>Background: </strong>The global prevalence of diseases transmitted by <i>Aedes aegypti</i> mosquitoes, such as dengue, Zika and Yellow Fever, is increasing, but development of promising new mosquito control technologies could reverse this trend. Target Product Profiles (TPPs) and Preferred Product Characteristics (PPCs) documents issued by the World Health Organization can guide the research and development pathways of new products and product combinations transitioning from proof of concept to operational use.</p><p><strong>Methods: </strong>We used high resolution global maps of the case and economic burden of dengue to derive programmatic cost targets to support a TPP for <i>Wolbachia</i> replacement. A compartmental entomological model was used to explore how release size, spacing and timing affect replacement speed and acceptability. To support a PPC for a hybrid suppress-then-replace approach we tested whether <i>Wolbachia</i> replacement could be achieved faster, more acceptably or at a lower cost if preceded by a mosquito suppression programme.</p><p><strong>Results: </strong>We show how models can reveal trade-offs, identify quantitative thresholds and prioritise areas and intervention strategies for further development. We estimate that for <i>Wolbachia</i> replacement to be deployable in enough areas to make major contributions to reducing global dengue burden by 25% (in line with 2030 WHO targets), it must have the potential for cost to be reduced to between $7.63 and $0.24 (USD) per person protected or less. Suppression can reduce the number of <i>Wolbachia</i> mosquitoes necessary to achieve replacement fixation by up to 80%. A hybrid approach can also achieve fixation faster and potentially improve acceptability, but may not justify their cost if they require major new investments in suppression technologies.</p><p><strong>Conclusions: </strong>Here we demonstrate the value dedicated modelling can provide for interdisciplinary groups of experts when developing TPPs and PPCs. These models could be used by product developers to prioritise and shape development decisions for new <i>Wolbachia</i> replacement products.</p>","PeriodicalId":12593,"journal":{"name":"Gates Open Research","volume":"7 ","pages":"68"},"PeriodicalIF":0.0,"publicationDate":"2024-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11549085/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142618159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vaccine decision-making among pregnant women: a protocol for a cross-sectional mixed-method study in Brazil, Ghana, Kenya and Pakistan.","authors":"Jessica L Schue, Prachi Singh, Berhaun Fesshaye, Emily S Miller, Shanelle Quinn, Ruth A Karron, Renato T Souza, Maria Laura Costa, Jose Guilherme Cecatti, Kwasi Torpey, Caroline Dinam Badzi, Emefa Modey, Chris Guure, Ferdinand Okwaro, Marleen Temmerman, Saleem Jessani, Sarah Saleem, Muhammad Asim, Sidrah Nausheen, Haleema Yasmeen, Grace Belayneh, Vanessa Brizuela, Sami Gottlieb, Rupali J Limaye","doi":"10.12688/gatesopenres.16280.1","DOIUrl":"10.12688/gatesopenres.16280.1","url":null,"abstract":"<p><p>Maternal immunization is a critical strategy to prevent both maternal and infant morbidity and mortality from several infectious diseases. When the first COVID-19 vaccines became available during the pandemic, there was mixed messaging and confusion amongst the broader public and among those associated with health care systems about the recommendations for COVID-19 vaccinations in pregnancy in many countries. A multi-country, mixed-methods study is being undertaken to describe how vaccine decision-making occurs amongst pregnant and postpartum women, with a focus on COVID-19 vaccines. The study is being conducted in Brazil, Ghana, Kenya, and Pakistan. In each country, participants are being recruited from either 2 or 3 maternity hospitals and/or clinics that represent a diverse population in terms of socio-economic and urban/rural status. Data collection includes cross-sectional surveys in pregnant women and semi-structured in-depth interviews with both pregnant and postpartum women. The instruments were designed to identify attitudinal, behavioral, and social correlates of vaccine uptake during and after pregnancy, including the decision-making process related to COVID-19 vaccines, and constructs such as risk perception, self-efficacy, vaccine intentions, and social norms. The aim is to recruit 400 participants for the survey and 50 for the interviews in each country. Qualitative data will be analyzed using a grounded theory approach. Quantitative data will be analyzed using descriptive statistics, latent variable analysis, and prediction modelling. Both the quantitative and qualitative data will be used to explore differences in attitudes and behaviors around maternal immunization across pregnancy trimesters and the postpartum period among and within countries. Each country has planned dissemination activities to share the study findings with relevant stakeholders in the communities from which the data is collected and to conduct country-specific secondary analyses.</p>","PeriodicalId":12593,"journal":{"name":"Gates Open Research","volume":"8 ","pages":"94"},"PeriodicalIF":0.0,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11489405/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142462816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulated data for census-scale entity resolution research without privacy restrictions: a large-scale dataset generated by individual-based modeling.","authors":"Beatrix Haddock, Alix Pletcher, Nathaniel Blair-Stahn, Os Keyes, Matt Kappel, Steve Bachmeier, Syl Lutze, James Albright, Alison Bowman, Caroline Kinuthia, Zeb Burke-Conte, Rajan Mudambi, Abraham Flaxman","doi":"10.12688/gatesopenres.15418.2","DOIUrl":"https://doi.org/10.12688/gatesopenres.15418.2","url":null,"abstract":"<p><strong>Background: </strong>Entity resolution (ER) is the process of identifying and linking records that refer to the same real-world entity. ER is a fundamental challenge in data science, and a common barrier to ER research and development is that the data fields used for this fuzzy matching are personally identifiable information, such as name, address, and date of birth. The necessary restrictions on accessing and sharing these authentic data have slowed the work in developing, testing, and adopting new methods and software for ER. We recently released <i>pseudopeople</i>, a Python package that allows users to generate simulated datasets with configurable noise approaching the scale and complexity of the data on which large organizations and federal agencies, like the US Census Bureau regularly perform ER. With pseudopeople, researchers can develop new algorithms and software for ER of US population data without needing access to personal and confidential information.</p><p><strong>Methods: </strong>We created the simulated population data available for noising with pseudopeople using our Vivarium simulation platform. Our model simulates individuals and their families, households, and employment dynamics over time, which we observe through simulated censuses, surveys, and administrative data collection systems.</p><p><strong>Results: </strong>Our simulation process produced over 900 gigabytes of simulated censuses, surveys, and administrative data for pseudopeople, representing hundreds of millions of simulants. A sample simulated population of thousands of simulants is now openly available to all users of the pseudopeople package, and large-scale simulated populations of millions and hundreds of millions of simulants are also available by online request through GitHub. These simulated population data are structured for use by the pseudopeople package, which includes additional affordances to add various kinds of noise to the data to provide realistic, sharable challenges for ER researchers.</p>","PeriodicalId":12593,"journal":{"name":"Gates Open Research","volume":"8 ","pages":"36"},"PeriodicalIF":0.0,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11518969/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142544960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stories of women's marriage and fertility experiences: Qualitative research on urban and rural cases in Bali, Indonesia.","authors":"Anastasia Septya Titisari, Luh Kadek Ratih Swandewi, Carol Warren, Anja Reid","doi":"10.12688/gatesopenres.14781.2","DOIUrl":"https://doi.org/10.12688/gatesopenres.14781.2","url":null,"abstract":"<p><p>As a Hindu-majority province in Indonesia, Bali presents a unique and distinctive culture. Patrilocal ( <i>purusa</i>) marriage and patrilineal inheritance as a continuation of the patriarchal system puts a male in the key role of family representative and successor. Having a son is a priority for a married couple in Balinese society. As a consequence, Balinese women experience several constraints related to their economic productive, reproductive, and <i>adat</i> (ritual) roles. When a family does not have a male heir, their daughter is pressed to find a spouse willing to accept <i>sentana</i> (daughter succession) marriage. This secondary form of marriage brings another complication for Balinese-Hindu women and does not necessarily relieve their submissive position. This study analyzes Balinese-Hindu women's perspectives on their marriage experiences and fertility decisions in patrilineal society in changing rural and urban conditions. The data was collected in two areas representing rural (Gianyar) and urban (Denpasar) locations in Bali Province, Indonesia from November 2019 to February 2020. Primary data was based on in-depth interviews of six rural and six urban married Balinese-Hindu women. This qualitative inquiry into Balinese women's experience of the marriage system and fertility options in urban and rural Bali revealed varying degrees of social expectation to provide male descendants for their families. At the same time, economic burdens still haunted them in this development era and manifested conflicting implications for family size. Their stories of <i>purusa</i> and <i>sentana</i> marriage were complex because it has strongly associated with customary law ( <i>adat</i>) in traditional society. Paradoxically, this study found that it was predominantly rural women who opted for the <i>sentana</i> arrangement and expressed a preference for smaller family sizes. This study explores women's fertility aspirations, notably regarding son precedence. It problematizes the <i>sentana</i> marriage alternative as a potential solution to alleviate the expectations and burdens placed on women.</p>","PeriodicalId":12593,"journal":{"name":"Gates Open Research","volume":"7 ","pages":"124"},"PeriodicalIF":0.0,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11480341/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142462758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Health care-seeking behavior for childhood illnesses in western Kenya: Qualitative findings from the Child Health and Mortality Prevention Surveillance (CHAMPS) Study.","authors":"Sarah Ngere, Maria Maixenchs, Sammy Khagayi, Peter Otieno, Kennedy Ochola, Kelvin Akoth, Aggrey Igunza, Benard Ochieng, Dickens Onyango, Victor Akelo, John Blevins, Beth A Tippett Barr","doi":"10.12688/gatesopenres.14866.2","DOIUrl":"10.12688/gatesopenres.14866.2","url":null,"abstract":"<p><strong>Background: </strong>Child mortality in Kenya is 41 per 1,000 live births, despite extensive investment in maternal, newborn, and child health interventions. Caregivers' health-seeking for childhood illness is an important determinant of child survival, and delayed healthcare is associated with high child mortality. We explore determinants of health-seeking decisions for childhood illnesses among caregivers in western Kenya.</p><p><strong>Methods: </strong>We conducted a qualitative study of 88 community members between April 2017 and February 2018 using purposive sampling in an informal urban settlement in Kisumu County, and in rural Siaya County. Key informant interviews, semi-structured interviews and focus group discussions were performed. We adopted the Partners for Applied Social Sciences model focusing on factors that influence the decision-making process to seek healthcare for sick infants and children. The discussions were audio-recorded and transcribed. Data management was completed on <i>Nvivo®</i> software. Iterative analysis process was utilized and themes were identified and collated.</p><p><strong>Results: </strong>Our findings reveal four thematic areas: Illness interpretation, the role of social relationship on illness recognition and response, medical pluralism and healthcare access. Participants reported some illnesses are caused by supernatural powers and some by biological factors, and that the illness etiology would determine the health-seeking pathway. It was common to seek consensus from respected community members on the diagnosis and therefore presumed cause and necessary treatment for a child's illness. Medical pluralism was commonly practiced and caregivers would alternate between biomedicine and traditional medicine. Accessibility of healthcare may determine the health seeking pathway. Caregivers unable to afford biomedical care may choose traditional medicine as a cheaper alternative.</p><p><strong>Conclusion: </strong>Health seeking behavior was driven by illness interpretation, financial cost associated with healthcare and advice from extended family and community. These findings enrich the perspectives of health education programs to develop health messages that address factors that hinder prompt health care seeking.</p>","PeriodicalId":12593,"journal":{"name":"Gates Open Research","volume":"8 ","pages":"31"},"PeriodicalIF":0.0,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11413273/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142283950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Child Health and Mortality Prevention Surveillance (CHAMPS): Manhiça site description, Mozambique.","authors":"Charfudin Sacoor, Pio Vitorino, Ariel Nhacolo, Khátia Munguambe, Rita Mabunda, Marcelino Garrine, Edgar Jamisse, Amílcar Magaço, Elísio Xerinda, António Sitoe, Fabíola Fernandes, Carla Carrilho, Maria Maixenchs, Percina Chirinda, Tacilta Nhampossa, Bento Nhancale, Natalia Rakislova, Justina Bramugy, Arsénio Nhacolo, Sara Ajanovic, Marta Valente, Arsénia Massinga, Rosauro Varo, Clara Menéndez, Jaume Ordi, Inácio Mandomando, Quique Bassat","doi":"10.12688/gatesopenres.13931.1","DOIUrl":"10.12688/gatesopenres.13931.1","url":null,"abstract":"<p><p>The Manhiça Health Research Centre (Manhiça HDSS) was established in 1996 in Manhiça, a rural district at Maputo Province in the southern part of Mozambique with approximately 49,000 inhabited households, a total population of 209.000 individuals, and an annual estimated birth cohort of about 5000 babies. Since 2016, Manhiça HDSS is implementing the Child Health and Mortality Prevention Surveillance (CHAMPS) program aiming to investigate causes of death (CoD) in stillbirths and children under the age of 5 years using an innovative post-mortem technique known as Minimally Invasive Tissue sampling (MITS), comprehensive pathogen screening using molecular methods, clinical record abstraction and verbal autopsy. Both in-hospital and community pediatric deaths are investigated using MITS. For this, community-wide socio-demographic approaches (notification of community deaths by key informants, formative research involving several segments of the community, availability of free phone lines for notification of medical emergencies and deaths, etc.) are conducted alongside to foster community awareness, involvement and adherence as well as to compute mortality estimates and collect relevant information of health and mortality determinants. The main objective of this paper is to describe the Manhiça Health and Demographic Surveillance System (HDSS) site and the CHAMPS research environment in place including the local capacities among its reference hospital, laboratories, data center and other relevant areas involved in this ambitious surveillance and research project, whose ultimate aim is to improve child survival through public health actions derived from credible estimates and understanding of the major causes of childhood mortality in Mozambique.</p>","PeriodicalId":12593,"journal":{"name":"Gates Open Research","volume":" ","pages":"4"},"PeriodicalIF":0.0,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11374382/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47401234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimating the impact of vaccination: lessons learned in the first phase of the Vaccine Impact Modelling Consortium.","authors":"Katy A M Gaythorpe, Xiang Li, Hannah Clapham, Emily Dansereau, Rich Fitzjohn, Wes Hinsley, Daniel Hogan, Mark Jit, Tewodaj Mengistu, T Alex Perkins, Allison Portnoy, Emilia Vynnycky, Kim Woodruff, Neil M Ferguson, Caroline L Trotter","doi":"10.12688/gatesopenres.15556.1","DOIUrl":"https://doi.org/10.12688/gatesopenres.15556.1","url":null,"abstract":"<p><p>Estimates of the global health impact of immunisation are important for quantifying historical benefits as well as planning future investments and strategy. The Vaccine Impact Modelling Consortium (VIMC) was established in 2016 to provide reliable estimates of the health impact of immunisation. In this article we examine the consortium in its first five-year phase. We detail how vaccine impact was defined and the methods used to estimate it as well as the technical infrastructure required to underpin robust reproducibility of the outputs. We highlight some of the applications of estimates to date, how these were communicated and what their effect were. Finally, we explore some of the lessons learnt and remaining challenges for estimating the impact of vaccines and forming effective modelling consortia then discuss how this may be addressed in the second phase of VIMC. Modelled estimates are not a replacement for surveillance; however, they can examine theoretical counterfactuals and highlight data gaps to complement other activities. VIMC has implemented strategies to produce robust, standardised estimates of immunisation impact. But through the first phase of the consortium, critical lessons have been learnt both on the technical infrastructure and the effective engagement with modellers and stakeholders. To be successful, a productive dialogue with estimate consumers, producers and stakeholders needs to be underpinned by a rigorous and transparent analytical framework as well as an approach for building expertise in the short and long term.</p>","PeriodicalId":12593,"journal":{"name":"Gates Open Research","volume":"8 ","pages":"97"},"PeriodicalIF":0.0,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11467163/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142462759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Power calculation for mosquito bioassays: Quantifying variability in the WHO tube bioassay and developing sample size guidance for the PBO synergism assay using a Shiny application.","authors":"Frank Mechan, Giorgio Praulins, Jack Gillespie, Katherine Gleave, Annabel Murphy-Fegan, Daniel P McDermott, David Weetman, Rosemary Susan Lees","doi":"10.12688/gatesopenres.16123.1","DOIUrl":"10.12688/gatesopenres.16123.1","url":null,"abstract":"<p><strong>Background: </strong>The WHO tube bioassay is a method for exposing mosquitos to determine susceptibility to insecticides, with mortality to discriminating doses <98% indicating possible resistance and <90% confirming resistance. This bioassay is also used for synergism testing to assess if susceptibility is restored by pre-exposure to the synergist piperonyl butoxide.</p><p><strong>Methods: </strong>Here we perform testing with pyrethroid-susceptible and pyrethroid-resistant <i>An. gambiae</i> to quantify the variability of the WHO tube bioassay and identify its sources. These estimates of within and between day variability are then used to evaluate the power of the bioassay to detect a mortality difference between pyrethroid-only and pyrethroid-PBO.</p><p><strong>Results: </strong>We show that approximately two-thirds of variation occurs between days, with the pyrethroid-susceptible strain twice as variable as the pyrethroid-resistant strain. The total number of mosquitoes in the tube and their bodyweight contributes to approximately 10% of this variability. Changes in temperature and humidity, within a climate-controlled insectary, didn't impact mortality. Using a simulation-based framework, we show that the current synergism guidelines, using a 4x4 design, can reliably detect a difference between 90% and 100% mortality (>90% power). However, as the mortality of either group gets closer to 50%, a 10% difference between groups is more difficult to reliably detect. In the worst-case scenario where the mortality of either group is 50%, the mortality difference must be >22.5% to be detected with 80% power. We provide an R shiny application to assess power for other comparisons.</p><p><strong>Conclusions: </strong>Our findings indicate that detecting synergism with the WHO tube assay is more difficult than assumed by the current WHO guidelines. Additionally, we demonstrate the value of using a Shiny application to make the outputs of simulation-based power analysis readily available to end-users, allowing them to determine the number of tubes needed to detect a given mortality difference.</p>","PeriodicalId":12593,"journal":{"name":"Gates Open Research","volume":"8 ","pages":"96"},"PeriodicalIF":0.0,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11576473/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142681490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}