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101.
Jeffrey David Connor Irvine Guerman Rolzing Kylie Doyle Nicholas Martel Tamara Tsang Vivian R. Ramsden 《Canadian family physician Médecin de famille canadien》2022,68(6):446
ObjectiveTo explore the perspectives and preferences of pregnant women receiving prenatal care in a rural community regarding delivery location.DesignExploratory qualitative research project.SettingThe La Ronge Medical Clinic in northern Saskatchewan.ParticipantsPregnant women of any parity aged 18 years or older who attended the clinic for prenatal care from March 1, 2018, to March 31, 2019, were invited to participate. The closest obstetric and surgical services are 240 km away.MethodsThis project was undertaken using semistructured interviews. The interviews were audiorecorded, transcribed, and analyzed using an inductive thematic analysis, taking into consideration both saturation and analyst triangulation. The investigators and researchers on this project were family medicine residents and faculty in a remote medical clinic.Main findingsThe factors that played a substantial role in influencing the patients’ decisions regarding delivery location included access to medical services, proximity to home community, perceptions of medical care providers, and some unique features of local hospitals. The participants largely believed they maintained their autonomy in selecting their preferred delivery location while seeking input from their prenatal care providers and families.ConclusionPregnant women in this rural community consider many factors when deciding on their delivery location. These findings can be taken into consideration by physicians when discussing with their rural patients the risks and benefits of delivery in both rural and urban centres. Barriers to local delivery should be addressed, while maintaining a woman’s autonomy to choose where she gives birth. 相似文献
102.
Jessica M. Franklin Wesley Eddings Peter C. Austin Elizabeth A. Stuart Sebastian Schneeweiss 《Statistics in medicine》2017,36(12):1946-1963
Nonrandomized studies of treatments from electronic healthcare databases are critical for producing the evidence necessary to making informed treatment decisions, but often rely on comparing rates of events observed in a small number of patients. In addition, studies constructed from electronic healthcare databases, for example, administrative claims data, often adjust for many, possibly hundreds, of potential confounders. Despite the importance of maximizing efficiency when there are many confounders and few observed outcome events, there has been relatively little research on the relative performance of different propensity score methods in this context. In this paper, we compare a wide variety of propensity‐based estimators of the marginal relative risk. In contrast to prior research that has focused on specific statistical methods in isolation of other analytic choices, we instead consider a method to be defined by the complete multistep process from propensity score modeling to final treatment effect estimation. Propensity score model estimation methods considered include ordinary logistic regression, Bayesian logistic regression, lasso, and boosted regression trees. Methods for utilizing the propensity score include pair matching, full matching, decile strata, fine strata, regression adjustment using one or two nonlinear splines, inverse propensity weighting, and matching weights. We evaluate methods via a ‘plasmode’ simulation study, which creates simulated datasets on the basis of a real cohort study of two treatments constructed from administrative claims data. Our results suggest that regression adjustment and matching weights, regardless of the propensity score model estimation method, provide lower bias and mean squared error in the context of rare binary outcomes. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
103.
Protectiveness of species sensitivity distribution hazard concentrations for acute toxicity used in endangered species risk assessment 总被引:2,自引:0,他引:2
Raimondo S Vivian DN Delos C Barron MG 《Environmental toxicology and chemistry / SETAC》2008,27(12):2599-2607
A primary objective of threatened and endangered species conservation is to ensure that chemical contaminants and other stressors do not adversely affect listed species. Assessments of the ecological risks of chemical exposures to listed species often rely on the use of surrogate species, safety factors, and species sensitivity distributions (SSDs) of chemical toxicity; however, the protectiveness of these approaches can be uncertain. We comprehensively evaluated the protectiveness of SSD first and fifth percentile hazard concentrations (HC1, HC5) relative to the application of safety factors using 68 SSDs generated from 1,482 acute (lethal concentration of 50%, or LC50) toxicity records for 291 species, including 24 endangered species (20 fish, four mussels). The SSD HC5s and HCls were lower than 97 and 99.5% of all endangered species mean acute LC50s, respectively. The HC5s were significantly less than the concentrations derived from applying safety factors of 5 and 10 to rainbow trout (Oncorhynchus mykiss) toxicity data, and the HCls were generally lower than the concentrations derived from a safety factor of 100 applied to rainbow trout toxicity values. Comparison of relative sensitivity (SSD percentiles) of broad taxonomic groups showed that crustaceans were generally the most sensitive taxa and taxa sensitivity was related to chemical mechanism of action. Comparison of relative sensitivity of narrow fish taxonomic groups showed that standard test fish species were generally less sensitive than salmonids and listed fish. We recommend the use of SSDs as a distribution-based risk assessment approach that is generally protective of listed species. 相似文献
104.
Amy C. Morrison Robert C. Reiner Jr. William H. Elson Helvio Astete Carolina Guevara Clara del Aguila Isabel Bazan Crystyan Siles Patricia Barrera Anna B. Kawiecki Christopher M. Barker Gissella M. Vasquez Karin Escobedo-Vargas Carmen Flores-Mendoza Alfredo A. Huaman Mariana Leguia Maria E. Silva Sarah A. Jenkins Wesley R. Campbell Eugenio J. Abente Robert D. Hontz Valerie A. Paz-Soldan John P. Grieco Neil F. Lobo Thomas W. Scott Nicole L. Achee 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(26)
Over half the world’s population is at risk for viruses transmitted by Aedes mosquitoes, such as dengue and Zika. The primary vector, Aedes aegypti, thrives in urban environments. Despite decades of effort, cases and geographic range of Aedes-borne viruses (ABVs) continue to expand. Rigorously proven vector control interventions that measure protective efficacy against ABV diseases are limited to Wolbachia in a single trial in Indonesia and do not include any chemical intervention. Spatial repellents, a new option for efficient deployment, are designed to decrease human exposure to ABVs by releasing active ingredients into the air that disrupt mosquito–human contact. A parallel, cluster-randomized controlled trial was conducted in Iquitos, Peru, to quantify the impact of a transfluthrin-based spatial repellent on human ABV infection. From 2,907 households across 26 clusters (13 per arm), 1,578 participants were assessed for seroconversion (primary endpoint) by survival analysis. Incidence of acute disease was calculated among 16,683 participants (secondary endpoint). Adult mosquito collections were conducted to compare Ae. aegypti abundance, blood-fed rate, and parity status through mixed-effect difference-in-difference analyses. The spatial repellent significantly reduced ABV infection by 34.1% (one-sided 95% CI lower limit, 6.9%; one-sided P value = 0.0236, z = 1.98). Aedes aegypti abundance and blood-fed rates were significantly reduced by 28.6 (95% CI 24.1%, ∞); z = −9.11) and 12.4% (95% CI 4.2%, ∞); z = −2.43), respectively. Our trial provides conclusive statistical evidence from an appropriately powered, preplanned cluster-randomized controlled clinical trial of the impact of a chemical intervention, in this case a spatial repellent, to reduce the risk of ABV transmission compared to a placebo.Aedes-borne viral diseases (ABVDs) [e.g., dengue (DENV), chikungunya, Zika (ZIKV), and yellow fever] are devastating, expanding global public health threats that disproportionally affect low- and middle-income countries. DENV, one of the most rapidly increasing vector-borne infectious diseases, results in ∼400 million infections each year (1, 2), with 4 billion people at risk for infection annually (3). Currently, the primary means for ABVD prevention is controlling the primary mosquito vector, Aedes aegypti. Existing vector control interventions, however, have failed to prevent ABV transmission and epidemics (4–6).There is an urgent need to develop evidence-based guidance for the use of new and existing ABV vector control tools. The evidence base for vector control against ABVs is weak, despite considerable government investments in World Health Organization (WHO)-recommended control of larval habitats (larviciding, container removal) and ultra-low-volume insecticide spraying (4, 5, 7–9). These strategies continue to be implemented despite the lack of rigorously generated data from controlled clinical trials demonstrating they reduce ABV infection or disease (6). The only ABV intervention with a proven epidemiological impact in a cluster-randomized control trial (cRCT) assessed community mobilization to reduce mosquito larval habitats (10). A recent test-negative trial with Wolbachia-infected mosquitoes reported a significant reduction of DENV illness in Indonesia (11).Spatial repellents (SRs) are devices that contain volatile active ingredients that disperse in air. The active ingredients can repel mosquitoes from entering a treated space, inhibit attraction to human host cues, or disrupt mosquito biting and blood-feeding behavior and, thus, interfere with mosquito–human contact (12–14). Any of these outcomes reduce the probability of pathogen transmission. Pyrethroid-based SRs have shown efficacy in reducing malaria infections in China (15) and Indonesia (16). There have, however, been no clinical trials evaluating the protective efficacy (PE) of SRs against ABV infection or disease.To generate evidence for public health consideration, we conducted a double-blinded, parallel cRCT to demonstrate and quantify the PE of a transfluthrin-based SR to reduce ABV infection incidence over 2 y in a human cohort in Iquitos, Peru. 相似文献
105.
Lisa Shea Jacqueline Pesa Gabrielle Geonnotti Valerie Powell Caryl Kahn Wesley Peters 《Health expectations》2022,25(4):1979
IntroductionThe lack of racial/ethnic diversity in research potentially limits the generalizability of findings to a broader population, highlighting the need for greater diversity and inclusion in clinical research. Qualitative research (i.e., focus groups) was conducted to identify (i) the potential motivators and barriers to study participation across different races and ethnicities; (ii) preferred delivery of education and information to support healthcare decision‐making and the role of the community.MethodsPatient focus groups were conducted with 26 participants from the sponsor''s Patient Engagement Research Councils selected through subjective sampling. Recruitment prioritized adequate representation across different race/ethnic groups. Participation was voluntary and participants underwent a confidential interview process before selection. Narrative analysis was used to identify themes and draw insights from interactions. Experienced research specialists identified emerging concepts, and these were tested against new observations. The frequency of each concept was examined to understand its importance.ResultsBased on self‐selected race/ethnicity, participants were divided into five focus groups (Groups: African American/Black: 2; Hispanic/Latino, Asian American, and white: 1 each) and were asked to share their experiences/opinions regarding the stated objectives. Barriers to study participation included: limited awareness of opportunities to participate in research, fears about changes in standard therapy, breaking cultural norms/stigma, religion‐related concerns and mistrust of clinical research. Participants identified the importance of transparency by pharmaceutical companies and other entities to build trust and partnership and cited key roles that communities can play. The perceptions of the African American group regarding diversity/inclusion in research studies appeared to be different from other groups; a lack of trust in healthcare providers, concerns about historical instances of research abuse and the importance of prayer were cited.ConclusionThis study provided insights into barriers to study participation, and also highlighted the need for pharmaceutical companies and other entities to authentically engage in strategies that build trust within communities to enhance recruitment among diverse populations.Patient or Public ContributionThe data collected in the present study was provided by the participants in the focus groups. 相似文献
106.
107.
Eric KamPui Lee Paul Poon ChunPong Yu Vivian WingYan Lee Vincent ChiHo Chung Samuel YeungShan Wong 《Journal of clinical hypertension (Greenwich, Conn.)》2022,24(5):529
Oral melatonin is a potential alternative treatment for hypertension and nocturnal hypertension. However, high‐quality and relevant meta‐analyses are lacking. This meta‐analysis aimed to investigate whether oral melatonin supplementation reduces daytime/asleep blood pressure and cardiovascular risk, improves sleep quality, and is well‐tolerated compared with placebo. Relevant articles were searched in multiple databases, including MEDLINE, EMBASE, CINAHL Complete, and the Cochrane Library, from their inception to June 2021. The included studies were randomized controlled trials recruiting patients with hypertension, using oral melatonin as the sole intervention, and investigating its effect on blood pressure. The mean out‐of‐office (including 24‐h, daytime, and asleep) systolic and diastolic blood pressures, sleep quality, and side effects were compared between the melatonin and placebo arms using pairwise random‐effect meta‐analyses. A risk of bias assessment was performed using the Cochrane risk‐of‐bias tool. Four studies were included in the analysis and only one study was considered to have a low risk of bias. No study reported on cardiovascular risk or outcomes. Only controlled‐release melatonin (not an immediate‐release preparation) reduced asleep systolic blood pressure by 3.57 mm Hg (95% confidence interval: –7.88 to .73; I2 = 0%). It also reduced asleep and awake diastolic blood pressure, but these differences were not statistically significant. Melatonin improves sleep efficacy and total sleep time and is safe and well‐tolerated. Due to the limited number of high‐quality trials, the quality of evidence was low to very low. Therefore, adequately powered randomized controlled trials on melatonin are warranted. 相似文献
108.
Flávia Giolo De Carvalho Flávia Troncon Rosa Vivian Marques Miguel Suen Ellen Cristini Freitas Gilberto José Padovan Julio Sérgio Marchini 《Nutrition (Burbank, Los Angeles County, Calif.)》2012,28(11-12):1127-1131
ObjectiveThe aim of this study was to assess the nutritional zinc (Zn) status of elite swimmers during different training periods.MethodsA longitudinal paired study was performed at the University of Sao Paulo in eight male swimmers 18 to 25 y old who had been swimming competitively at the state and national levels for at least 5 y. The swimmers were evaluated over a total period of 14 wk: before the basic and specific preparatory period (BSPP-baseline), at the end of the basic and specific preparatory period (post-BSPP), and at the end of the polishing period (PP). Levels of Zn were determined in the plasma, erythrocyte, urine, and saliva by atomic absorption spectrophotometry. Anthropometric measurements and a 3-d food record were also evaluated.ResultsThe median plasma Zn concentration was below the reference value in all training periods (BSPP-baseline 59 μg/dL, post-BSPP 55.9 μg/dL, after PP 58.8 μg/dL, P > 0.05), as were threshold values for erythrocytes (BSPP-baseline 36.5 μg of Zn/g of hemoglobin, post-BSPP 42 μg of Zn/g of hemoglobin, after PP 40.7 μg of Zn/g of hemoglobin, P > 0.05), urinary Zn (BSPP-baseline 280 μg/24 h, post-BSPP 337 μg/24 h, after PP 284 μg/24 h, P > 0.05), and salivary Zn (BSPP-baseline 66.1 μg/L, post-BSPP 54.1 μg/L, after PP 79.7 μg/L, P > 0.05). Salivary Zn did not correlate with plasma and erythrocyte Zn levels.ConclusionThe results suggest that the elite swimmers studied presented a possible Zn deficiency and that salivary Zn was not adequate to evaluate the Zn nutritional status. 相似文献
109.
Emily A. Rauscher Stephanie L. Young Wesley T. Durham Joshua B. Barbour 《Health communication》2017,32(5):550-559
This study investigates how young women of egg-donating age perceive egg donation. Using institutional theory, this study demonstrates how participants frame a health care decision, such as egg donation, utilizing familial ideals. Results revealed that women expressed the importance of ownership over their genetic material and that familial ideals encourage an ideal way to create a family, which egg donation only fits as a last resort. Results show that familial ideals reach past the institution of family into broader decision making, such as that of health care. Further, results show that as more families are constructed through assisted reproductive technologies, attempts should be made to gradually alter the familial ideal to encompass novel medical technologies such as egg donation. 相似文献
110.
Vivian H. Y. Ip MBChB Mark C. Rockley BScH Ban C. H. Tsui MD 《Journal canadien d'anesthésie》2013,60(12):1272-1273