56 research outputs found
Assessing Bias in Population Size Estimates Among Hidden Populations When Using the Service Multiplier Method Combined With Respondent-Driven Sampling Surveys: Survey Study.
BACKGROUND: Population size estimates (PSEs) for hidden populations at increased risk of HIV, including female sex workers (FSWs), are important to inform public health policy and resource allocation. The service multiplier method (SMM) is commonly used to estimate the sizes of hidden populations. We used this method to obtain PSEs for FSWs at 9 sites in Zimbabwe and explored methods for assessing potential biases that could arise in using this approach. OBJECTIVE: This study aimed to guide the assessment of biases that arise when estimating the population sizes of hidden populations using the SMM combined with respondent-driven sampling (RDS) surveys. METHODS: We conducted RDS surveys at 9 sites in late 2013, where the Sisters with a Voice program (the program), which collects program visit data of FSWs, was also present. Using the SMM, we obtained PSEs for FSWs at each site by dividing the number of FSWs who attended the program, based on program records, by the RDS-II weighted proportion of FSWs who reported attending this program in the previous 6 months in the RDS surveys. Both the RDS weighting and SMM make a number of assumptions, potentially leading to biases if the assumptions are not met. To test these assumptions, we used convergence and bottleneck plots to assess seed dependence of RDS-II proportion estimates, chi-square tests to assess if there was an association between the characteristics of FSWs and their knowledge of program existence, and logistic regression to compare the characteristics of FSWs attending the program with those recruited to RDS surveys. RESULTS: The PSEs ranged from 194 (95% CI 62-325) to 805 (95% CI 456-1142) across 9 sites from May to November 2013. The 95% CIs for the majority of sites were wide. In some sites, the RDS-II proportion of women who reported program use in the RDS surveys may have been influenced by the characteristics of selected seeds, and we also observed bottlenecks in some sites. There was no evidence of association between characteristics of FSWs and knowledge of program existence, and in the majority of sites, there was no evidence that the characteristics of the populations differed between RDS and program data. CONCLUSIONS: We used a series of rigorous methods to explore potential biases in our PSEs. We were able to identify the biases and their potential direction, but we could not determine the ultimate direction of these biases in our PSEs. We have evidence that the PSEs in most sites may be biased and a suggestion that the bias is toward underestimation, and this should be considered if the PSEs are to be used. These tests for bias should be included when undertaking population size estimation using the SMM combined with RDS surveys
Limited heat tolerance in a cold-adapted seabird: Implications of a warming Arctic
The Arctic is warming at approximately twice the global rate, with welldocumented indirect effects on wildlife. However, few studies have examined the direct effects of warming temperatures on Arctic wildlife, leaving the importance of heat stress unclear. Here, we assessed the direct effects of increasing air temperatures on the physiology of thick-billed murres (Uria lomvia), an Arctic seabird with reported mortalities due to heat stress while nesting on sun-exposed cliffs.We used flow-through respirometry to measure the response of body temperature, resting metabolic rate, evaporative water loss and evaporative cooling efficiency (the ratio of evaporative heat loss to metabolic heat production) in murres while experimentally increasing air temperature. Murres had limited heat tolerance, exhibiting: (1) a low maximum body temperature (43.3°C); (2) a moderate increase in resting metabolic rate relative that within their thermoneutral zone (1.57 times); (3) a small increase in evaporative water loss rate relative that within their thermoneutral zone (1.26 times); and (4) a low maximum evaporative cooling efficiency (0.33). Moreover, evaporative cooling efficiency decreased with increasing air temperature, suggesting murres were producing heat at a faster rate than they were dissipating it. Larger murres also had a higher rate of increase in resting metabolic rate and a lower rate of increase in evaporative water loss than smaller murres; therefore, evaporative cooling efficiency declined with increasing body mass. As a coldadapted bird, murres\u27 limited heat tolerance likely explains their mortality on warm days. Direct effects of overheating on Arctic wildlife may be an important but under-reported impact of climate change
Evaluating the impact of an intervention to increase uptake of modern contraceptives among adolescent girls (15-19 years) in Nigeria, Ethiopia and Tanzania: the Adolescents 360 quasi-experimental study protocol.
INTRODUCTION: Nigeria, Ethiopia and Tanzania have some of the highest teenage pregnancy rates and lowest rates of modern contraceptive use among adolescents. The transdisciplinary Adolescents 360 (A360) initiative being rolled out across these three countries uses human-centred design to create context-specific multicomponent interventions with the aim of increasing voluntary modern contraceptive use among girls aged 15-19 years. METHODS: The primary objective of the outcome evaluation is to assess the impact of A360 on the modern contraceptive prevalence rate (mCPR) among sexually active girls aged 15-19 years. A360 targets different subpopulations of adolescent girls in the three countries. In Northern Nigeria and Ethiopia, the study population is married girls aged 15-19 years. In Southern Nigeria, the study population is unmarried girls aged 15-19 years. In Tanzania, both married and unmarried girls aged 15-19 years will be included in the study. In all settings, we will use a prepopulation and postpopulation-based cross-sectional survey design. In Nigeria, the study design will also include a comparison group. A one-stage sampling design will be used in Nigeria and Ethiopia. A two-stage sampling design will be used in Tanzania. Questionnaires will be administered face-to-face by female interviewers aged between 18 and 26 years. Study outcomes will be assessed before the start of A360 implementation in late 2017 and approximately 24 months after implementation in late 2019. ETHICS AND DISSEMINATION: Findings of this study will be widely disseminated through workshops, conference presentations, reports, briefings, factsheets and academic publications
This needs to be a journey that we’re actually on together’—the introduction of integrated care systems for children and young people in England: a qualitative study of the views of local system stakeholders during winter 2021/22
Background: Integrated care has become a central feature of health system reform worldwide. In England, Integrated Care Systems (ICS) are intended to improve integration across public health, the National Health Service (NHS), education and social care. By April 2021, England had been divided into 42 geographical areas, each tasked with developing local ICS provision. However, it was not clear how ICSs would address the specific needs of children and young people (CYP). This study elicited the views of senior professional stakeholders in the first year of the ICS national roll out, to learn how integrated care for CYP was being implemented within the ICSs and future plans for service provision. Methods: A qualitative analysis of in-depth interviews with stakeholders, including healthcare professionals, NHS managers and local authority leaders (n = 25) selected from a diverse sample of ICSs (n = 7) across England, conducted during winter 2021/22. Reflexive thematic analysis involving a collaborative coding approach was used to analyse interview transcripts. Results: Four themes were identified, indicating challenges and opportunities for ICSs in relation to the health of CYP: 1) Best start in life (a more holistic approach to health afforded by integrated care); 2) Local and national contexts (tensions between local and national settings and priorities); 3) Funding and planning (instituting innovative, long-term plans using limited existing CYP funding streams); 4) Organisational complexities (integrating the work of diverse organisations). Conclusions: The views of stakeholders, provided at the beginning of the journey towards developing local ICS CYP provision, revealed a common aspiration to change focus from provision of acute, largely adult-orientated services towards one with a broader, population health remit, including prevention and early intervention. This would be delivered by integration of a range of local services, including health, education, housing and social care, to set CYP on a life-long path towards improved health and wellbeing. Yet there was an awareness that change would take place over time within existing national policy and funding frameworks, and would require overcoming organisational barriers through further developing local collaborations and partnerships. As ICSs mature, the experiences of stakeholders should continue to be canvassed to identify practical lessons for successful CYP integrated care
'This needs to be a journey that we're actually on together'—the introduction of integrated care systems for children and young people in England: a qualitative study of the views of local system stakeholders during winter 2021/22
Background: Integrated care has become a central feature of health system reform worldwide. In England, Integrated Care Systems (ICS) are intended to improve integration across public health, the National Health Service (NHS), education and social care. By April 2021, England had been divided into 42 geographical areas, each tasked with developing local ICS provision. However, it was not clear how ICSs would address the specific needs of children and young people (CYP). This study elicited the views of senior professional stakeholders in the first year of the ICS national roll out, to learn how integrated care for CYP was being implemented within the ICSs and future plans for service provision. /
Methods: A qualitative analysis of in-depth interviews with stakeholders, including healthcare professionals, NHS managers and local authority leaders (n = 25) selected from a diverse sample of ICSs (n = 7) across England, conducted during winter 2021/22. Reflexive thematic analysis involving a collaborative coding approach was used to analyse interview transcripts. /
Results: Four themes were identified, indicating challenges and opportunities for ICSs in relation to the health of CYP: 1) Best start in life (a more holistic approach to health afforded by integrated care); 2) Local and national contexts (tensions between local and national settings and priorities); 3) Funding and planning (instituting innovative, long-term plans using limited existing CYP funding streams); 4) Organisational complexities (integrating the work of diverse organisations). /
Conclusions: The views of stakeholders, provided at the beginning of the journey towards developing local ICS CYP provision, revealed a common aspiration to change focus from provision of acute, largely adult-orientated services towards one with a broader, population health remit, including prevention and early intervention. This would be delivered by integration of a range of local services, including health, education, housing and social care, to set CYP on a life-long path towards improved health and wellbeing. Yet there was an awareness that change would take place over time within existing national policy and funding frameworks, and would require overcoming organisational barriers through further developing local collaborations and partnerships. As ICSs mature, the experiences of stakeholders should continue to be canvassed to identify practical lessons for successful CYP integrated care
Limited heat tolerance in an Arctic passerine: Thermoregulatory implications for cold-specialized birds in a rapidly warming world
Arctic animals inhabit some of the coldest environments on the planet and have evolved physiological mechanisms for minimizing heat loss under extreme cold. However, the Arctic is warming faster than the global average and how well Arctic animals tolerate even moderately high air temperatures (Ta) is unknown. Using flow-through respirometry, we investigated the heat tolerance and evaporative cooling capacity of snow buntings (Plectrophenax nivalis; ≈31 g, N = 42), a cold specialist, Arctic songbird. We exposed buntings to increasing Ta and measured body temperature (Tb), resting metabolic rate (RMR), rates of evaporative water loss (EWL), and evaporative cooling efficiency (the ratio of evaporative heat loss to metabolic heat production). Buntings had an average (±SD) Tb of 41.3 ± 0.2°C at thermoneutral Ta and increased Tb to a maximum of 43.5 ± 0.3°C. Buntings started panting at Ta of 33.2 ± 1.7°C, with rapid increases in EWL starting at Ta = 34.6°C, meaning they experienced heat stress when air temperatures were well below their body temperature. Maximum rates of EWL were only 2.9× baseline rates at thermoneutral Ta, a markedly lower increase than seen in more heat-tolerant arid-zone species (e.g., ≥4.7× baseline rates). Heat-stressed buntings also had low evaporative cooling efficiencies, with 95% of individuals unable to evaporatively dissipate an amount of heat equivalent to their own metabolic heat production. Our results suggest that buntings’ well-developed cold tolerance may come at the cost of reduced heat tolerance. As the Arctic warms, and this and other species experience increased periods of heat stress, a limited capacity for evaporative cooling may force birds to increasingly rely on behavioral thermoregulation, such as minimizing activity, at the expense of diminished performance or reproductive investment
Associations between HIV stigma and health-related quality-of-life among people living with HIV: cross-sectional analysis of data from HPTN 071 (PopART)
People living with HIV (PLHIV) report lower health-related quality-of-life (HRQoL) than HIV-negative people. HIV stigma may contribute to this. We explored the association between HIV stigma and HRQoL among PLHIV. We used cross-sectional data from 3991 randomly selected PLHIV who were surveyed in 2017–2018 for HPTN 071 (PopART), a cluster randomised trial in Zambia and South Africa. Participants were 18–44 years, had laboratory-confirmed HIV infection, and knew their status. HRQoL was measured using the EuroQol-5-dimensions-5-levels (EQ-5D-5L) questionnaire. Stigma outcomes included: internalised stigma, stigma experienced in the community, and stigma experienced in healthcare settings. Associations were examined using logistic regression. Participants who had experienced community stigma (n = 693/3991) had higher odds of reporting problems in at least one HRQoL domain, compared to those who had not (adjusted odds ratio, aOR: 1.51, 95% confidence interval, 95% Cl: 1.16–1.98, p = 0.002). Having experienced internalised stigma was also associated with reporting problems in at least one HRQoL domain (n = 552/3991, aOR: 1.98, 95% CI: 1.54–2.54, p < 0.001). However, having experienced stigma in a healthcare setting was less common (n = 158/3991) and not associated with HRQoL (aOR: 1.04, 95% CI: 0.68–1.58, p = 0.850). A stronger focus on interventions for internalised stigma and stigma experienced in the community is required
Sexuality, fertility and family planning characteristics of married women aged 15 to 19 years in Ethiopia, Nigeria and Tanzania: a comparative analysis of cross-sectional data.
BACKGROUND: Adolescents 360 (A360) is an initiative being rolled out across Ethiopia, Nigeria and Tanzania with the aim of increasing uptake of voluntary modern contraception among sexually active women aged 15 to 19 years. Using evaluation baseline survey data, we described key sexuality, fertility and contraceptive use characteristics of married women aged 15 to 19 years living in three sub-national settings. METHODS: Cross-sectional baseline surveys of married women aged 15 to 19 years were conducted in Oromia (Ethiopia), Nasarawa (Northern Nigeria), and Mwanza (Tanzania) between August 2017 and February 2018. We also interviewed the husbands of a sub-group of married respondents to measure spousal acceptance and support for adolescent women to use modern contraception. A clustered sampling design was used in all three countries. We produced descriptive statistics on the socio-demographic and sexual and reproductive health characteristics of married women aged 15 to 19 years by study setting. RESULTS: In Oromia, Nasarawa and Mwanza, 31.4% (327/1198), 27.4% (1321/4816) and 7.5% (15/201) of married women surveyed had no education, and 68.3, 81.3 and 83.1% had ever been pregnant, respectively. Unmet need for modern contraception was 20.5, 21.9 and 32.0% in married women in Oromia, Nasarawa and Mwanza, made up almost entirely of unmet need for spacing. The vast majority of married women surveyed in Oromia (89.1%) and Mwanza (90.1%) had seen or heard about contraception in the last 12 months, compared to 30.1% of those surveyed in Nasarawa. Modern contraceptive prevalence (mCPR) was highest in married women aged 15 to 19 years in Oromia (47.2%), followed by Mwanza (19.4%) and Nasarawa (8.7%). Of those using a modern method of contraception in Oromia, 93.4% were using injectables or long-acting methods, compared to 49.4% in Nasarawa and 69.6% in Mwanza. CONCLUSIONS: Overall, unmet need for modern contraception is high among married women aged 15 to 19 years across the three settings. mCPR for married women aged 15 to 19 years is low in Nasarawa and Mwanza. Ultimately, no single intervention will suit all situations, but improving the quality, analyses and utilisation of subnational data can help decision-makers design more context specific interventions
Allogeneic Ex Vivo Expanded Corneal Epithelial Stem Cell Transplantation: A Randomized Controlled Clinical Trial:Allogeneic Limbal Stem Cell Therapy
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