250 research outputs found

    Citation classics in systematic reviews and meta-analyses : who wrote the top 100 most cited articles?

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    Background: Systematic reviews of the literature occupy the highest position in currently proposed hierarchies of evidence. The aims of this study were to assess whether citation classics exist in published systematic review and meta-analysis (SRM), examine the characteristics of the most frequently cited SRM articles, and evaluate the contribution of different world regions. Methods: The 100 most cited SRM were identified in October 2012 using the Science Citation Index database of the Institute for Scientific Information. Data were extracted by one author. Spearman’s correlation was used to assess the association between years since publication, numbers of authors, article length, journal impact factor, and average citations per year. Results: Among the 100 citation classics, published between 1977 and 2008, the most cited article received 7308 citations and the least-cited 675 citations. The average citations per year ranged from 27.8 to 401.6. First authors from the USA produced the highest number of citation classics (n=46), followed by the UK (n=28) and Canada (n=15). The 100 articles were published in 42 journals led by the Journal of the American Medical Association (n=18), followed by the British Medical Journal (n=14) and The Lancet (n=13). There was a statistically significant positive correlation between number of authors (Spearman’s rho=0.320, p=0.001), journal impact factor (rho=0.240, p=0.016) and average citations per year. There was a statistically significant negative correlation between average citations per year and year since publication (rho = -0.636, p=0.0001). The most cited papers identified seminal contributions and originators of landmark methodological aspects of SRM and reflect major advances in the management of and predisposing factors for chronic diseases. Conclusions: Since the late 1970s, the USA, UK, and Canada have taken leadership in the production of citation classic papers. No first author from low or middle-income countries (LMIC) led one of the most cited 100 SRM

    The impact of mass media interventions on tuberculosis awareness, health-seeking behaviour and health service utilisation : a systematic review protocol

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    Introduction: Tuberculosis (TB) is a serious public health problem in many parts of the world. Strategies to curb the spread of TB must match the multifaceted nature of the epidemic. The use of mass media is one of the important strategies in communicating behavioural change in relation to TB prevention and the treatment. However, the benefits of this intervention are unclear. We, therefore, plan to conduct a systematic review on the effects of mass media interventions on TB awareness, health-seeking behaviour and health service utilisation. Methods and analysis: We will preferably include randomised controlled trials (RCTs) in this systematic review. However, non-randomised studies will be included if there is an inadequate number of RCTs. We will perform electronic searches in PubMed, Scopus and other databases, along with manual searches. Articles written (or translated) in English and French and published between 1 January 1980 and 31 October 2013 will be eligible for inclusion in this review. The primary outcomes will be TB knowledge, attitudes and awareness, healthcare-seeking behaviour and service utilisation. The secondary outcomes will include stigma and discrimination against people with TB and the costs of the interventions. We will investigate clinical and statistical heterogeneity and pool studies judged to be clinically and statistically homogeneous. Relative risks will be calculated for dichotomous outcomes and mean differences for continuous outcomes, both with their corresponding 95% CIs. Ethics and dissemination: The systematic review will use data that is not linked to individuals. The review findings may have implications for clinical practice and future research, and will be disseminated electronically and in print through peer-reviewed publications

    Randomised trials of COVID-19 vaccines in Africa – charting the path forward.

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    Vaccines have played a critical role in controlling disease outbreaks, hence the proliferation of the development and testing of multiple vaccine candidates during the COVID-19 pandemic. Randomised trials are gold standards for evaluating the safety and efficacy of pharmaceutical interventions such as COVID-19 vaccines. However, contextual differences may attenuate effects of COVID-19 vaccines. Thus, the need to conduct COVID-19 vaccine trials in all settings, including in Africa. We conducted a crosssectional analysis of planned, ongoing, and completed COVID-19 vaccine trials in Africa. We searched the South African National Clinical Trials Register, Pan African Clinical Trials Registry, and International Clinical Trials Registry Platform (ICTRP) on 12 January and 30 April 2022; and complemented this with a search of ClinicalTrials.gov on 17 May 2022. We screened the search output and included randomised trials with at least one recruitment site in Africa. We identified only 108 eligible trials: 90 (83%) evaluating candidate COVID-19 vaccines, 11 (10%) assessing if existing vaccines could prevent SARS-CoV-2 infection, and 7 (7%) evaluating interventions for improving COVID-19 vaccination coverage. South Africa had the highest number of trials at 58 (54%). Beyond South Africa, countries with more than 10 trial sites include Kenya, Ghana, Egypt, Uganda, and Zimbabwe. Among the trials, 14 (13%) do not have principal investigators based in Africa, 39 (30%) are funded by industry, and 91 (84%) are funded by institutions based outside the host country. COVID-19 vaccine trials with recruitment sites in Africa represented only 7% of the 1453 COVID-19 vaccine trials in the ICTRP. The paucity of COVID-19 vaccine trials conducted on the African continent is a cause for concern. This has implications for the role that Africa may play in future pandemics.Significance:• There are generally very few vaccine trials conducted in Africa, relative to the rest of the world.• The limited vaccine trials in Africa could be attributed to limited expertise and resources, both human and material, as well as lack of perceived market.• It is reassuring that many COVID-19 vaccines are planned, being conducted, or have been conducted in multiple African countries; but there is a need for more African public sector funding for vaccine trials on the continent

    The Cochrane Corner in the SAMJ: Summaries of Cochrane systematic reviews for evidence-informed practice

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    This editorial introduces a regular contribution from Cochrane South Africa (http://www.mrc.ac.za/cochrane/cochrane.htm) to the South African Medical Journal, which will be called the ‘Cochrane Corner’. Our contribution takes the form of technical summaries of Cochrane systematic reviews handpicked for their relevance to South Africa and the African region. Our goal is to help ensure that the high-quality evidence in Cochrane reviews reaches a wider audience.

    Mobile phone text messaging for promoting adherence to anti-tuberculosis treatment: a systematic review protocol

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    BACKGROUND: In 2010, there were approximately 8.8 million incident cases of tuberculosis (TB) worldwide. The treatment of TB is at least six months long and may be complicated by a high pill burden. In addition, TB patients often do not take their medication on schedule simply because they forget. Mobile phone text messaging has the potential to help promote TB treatment adherence. We, therefore, propose to conduct a review of current best evidence for the use of mobile phone text messaging to promote patient adherence to TB treatment. METHODS: This is a systematic review of the literature. We will preferably include randomized controlled trials (RCTs). However, non-randomized studies (NRS) will be considered if there is an inadequate number of RCTs.We will search PubMed, EMBASE, CINAHL, CENTRAL, Science Citation Index, Africa-Wide Information, and WHOLIS electronic databases for eligible studies available by 30 November 2012 regardless of language or publication status. We will also check reference lists for additional studies, identify abstracts from conference proceedings and communicate with authors for any relevant material.At least two authors will independently screen search outputs, select studies, extract data and assess the risk of bias (using separate criteria for RCTs and NRS); resolving discrepancies by discussion and consensus. We will assess clinical heterogeneity by examining the types of participants, interventions and outcomes in each study and pool studies judged to be clinically homogenous. We will also assess statistical heterogeneity using the chi-square test of homogeneity and quantify it using the I-square statistic. If study results are found to be statistically homogeneous (that is heterogeneity P > 0.1), we will pool them using the fixed-effect meta-analysis. Otherwise, we will use random-effects meta-analysis. We will calculate risk ratios and their corresponding 95% confidence intervals for dichotomous outcomes, and mean differences for continuous outcomes. For other outcomes without quantitative data, a descriptive analysis will be used.DISCUSSION:Our results can be used by researchers and policy-makers to help inform them of the efficacy of mobile phone text messaging interventions to promote patient adherence to TB treatment

    Trends in the types and quality of childhood immunisations research output from Africa 1970–2010: mapping the evidence base

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    Abstract Background Over the past four decades, extraordinary progress has been made in establishing and improving childhood immunization programmes around Africa. In order to ensure effective and sustainable positive growth of these childhood immunisations programmes, the development, adaptation and implementation of all interventions (programme activities, new vaccines, new strategies and policies) should be informed by the best available local evidence. Methods An assessment of the peer-reviewed literature on childhood immunization research published in English from 1970 to 2010 was conducted in PubMed and Africa-Wide databases. All study types were eligible for inclusion. A standard form was used to extract information from all studies identified as relevant and entered into a Microsoft Access database for analysis. Results Our initial search yielded 5436 articles from the two databases, from which 848 full text articles were identified as relevant. Among studies classified as clinical research (417), 40% were clinical trials, 24% were burden of disease/epidemiology and 36% were other clinical studies. Among studies classified as operational research (431), 77% related to programme management, 18% were policy related and 5% were related to vaccine financing. Studies were conducted in 48 African countries with six countries (South Africa, The Gambia, Nigeria, Senegal, Guinea-Bissau and Kenya) accounting for 56% of the total research output. Studies were published in 152 different journals with impact factors ranging from 0.192 to 53.29; with a median impact factor of 3.572. Conclusion A similar proportion of clinical versus operational research output was found. However, an uneven distribution across Africa was observed with only six countries accounting for over half of the research output. The research conducted was of moderate to high quality, with 62% being published in journals with 2010 impact factors greater than two. Urgent attention should be given to the development of research capacity in low performing countries around Africa, with increased focus on the process of turning immunisations programme research evidence into policy and practice, as well as increased focus on issues relating to vaccine financing and sustainability in Africa

    Strengthening the expanded programme on immunization in Africa: looking beyond 2015

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    Shingai Machingaidze and colleagues reflect on the successes and shortfalls of the Expanded Programme on Immunization (EPI) in Africa, and the considerable challenges that must now be addressed to improve immunization systems

    Global health: the importance of evidence-based medicine

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    Global health is a varied field that comprises research, evaluation and policy that, by its definition, also occurs in disparate locations across the world. This forum article is introduced by our guest editor of the Medicine for Global Health article collection, Gretchen Birbeck. Here, experts based across different settings describe their personal experiences of global health, discussing how evidence-based medicine in resource-limited settings can be translated into improved health outcomes

    COVID-19 and routine childhood immunization in Africa : leveraging systems thinking and implementation science to improve immunization system performance

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    CITATION: Adamu, A. A. et al. 2020. COVID-19 and routine childhood immunization in Africa: Leveraging systems thinking and implementation science to improve immunization system performance. International journal of infectious diseases, 98:161–165. doi:10.1016/j.ijid.2020.06.072The original publication is available at https://www.journals.elsevier.com/international-journal-of-infectious-diseasesOne of the routine health services that is being disrupted by coronavirus disease 2019 (COVID-19) in Africa is childhood immunization. This is because the immunization system relies on functioning health facilities and stable communities to be effective. Its disruption increases the risk of epidemics of vaccine-preventable diseases, which could increase child mortality. Therefore, policymakers must quickly identify robust and context-specific strategies to rapidly scale-up routine immunization in order to mitigate the impact of COVID-19 on their national immunization performance. To achieve this, we propose a paradigm shift towards systems thinking and use of implementation science in immunization decision-making. Systems thinking can inform a more nuanced and holistic understanding of the interrelationship between COVID-19, its control strategies, and childhood immunization. Tools like causal loop diagrams can be used to explicitly illustrate the systems structure by identifying feedback loops. Once mapped and leverage points for interventions have been identified, implementation science can be used to guide the rapid uptake and utilization of multifaceted evidence-based innovations in complex practice settings. As Africa re-strategizes for the post-2020 era, these emerging fields could contribute significantly in accelerating progress towards universal access to vaccines for all children on the continent despite COVID-19.https://www.clinicalkey.com/#!/content/playContent/1-s2.0-S1201971220305075?returnurl=https:%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS1201971220305075%3Fshowall%3Dtrue&referrer=Publishers versio

    A review of adherence and predictors of adherence to the CONSORT Statement in the reporting of tuberculosis vaccine trials

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    CITATION: Ngah, V. D. et al. 2020. A review of adherence and predictors of adherence to the CONSORT Statement in the reporting of tuberculosis vaccine trials. Vaccines, 8(4):770, doi:10.3390/vaccines8040770.The original publication is available at https://www.mdpi.comThe statement on Consolidated Standards of Reporting Trials (CONSORT) ensures transparency in the reporting of randomized trials. However, it is unclear if the statement has led to improvement in the quality of reporting of tuberculosis (TB) vaccine trials. We explored the quality of reporting of TB vaccine trials according to the latest version of the CONSORT statement, released in 2010. We searched PubMed and the Cochrane Central Register of Controlled Trials in August 2019. We conducted screening, study selection, and data extraction in duplicate; and resolved differences through discussion. We assessed reporting to be adequate if trials reported at least 75% of the CONSORT 2010 items. We conducted a trend analysis to assess if there was improvement in reporting over time. We also used logistic regression to assess factors associated with adequate reporting. We included 124 trials in the analyses. The mean proportion of adherence was 67.3% (95% confidence interval 64.4% to 70.1%), with only 46 (37%) trials having adequate reporting. There was a significant improvement in the quality of reporting over time (p < 0.0001). Trials published in journals with impact factors between 10 and 20 were more likely to have adequate reporting (odds ratio 9.4; 95% confidence interval 1.30 to 67.8), compared to lower-impact-factor journals. Despite advances over time, the reporting of TB vaccine trials is still inadequate and requires improvement.https://www.mdpi.com/2076-393X/8/4/770Publisher's versio
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