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Find video protocols related to scientific articles indexed in Pubmed.
Regression discontinuity designs in epidemiology: causal inference without randomized trials.
Epidemiology
PUBLISHED: 07-26-2014
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When patients receive an intervention based on whether they score below or above some threshold value on a continuously measured random variable, the intervention will be randomly assigned for patients close to the threshold. The regression discontinuity design exploits this fact to estimate causal treatment effects. In spite of its recent proliferation in economics, the regression discontinuity design has not been widely adopted in epidemiology. We describe regression discontinuity, its implementation, and the assumptions required for causal inference. We show that regression discontinuity is generalizable to the survival and nonlinear models that are mainstays of epidemiologic analysis. We then present an application of regression discontinuity to the much-debated epidemiologic question of when to start HIV patients on antiretroviral therapy. Using data from a large South African cohort (2007-2011), we estimate the causal effect of early versus deferred treatment eligibility on mortality. Patients whose first CD4 count was just below the 200 cells/?L CD4 count threshold had a 35% lower hazard of death (hazard ratio = 0.65 [95% confidence interval = 0.45-0.94]) than patients presenting with CD4 counts just above the threshold. We close by discussing the strengths and limitations of regression discontinuity designs for epidemiology.
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The changing face of the HIV epidemic in sub-Saharan Africa.
Trop. Med. Int. Health
PUBLISHED: 06-27-2014
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The widespread roll-out of antiretroviral therapy (ART) has substantially changed the face of human immunodeficiency virus (HIV). Timely initiation of ART in HIV-infected individuals dramatically reduces mortality and improves employment rates to levels prior to HIV infection. Recent findings from several studies have shown that ART reduces HIV transmission risk even with modest ART coverage of the HIV-infected population and imperfect ART adherence. While condoms are highly effective in the prevention of HIV acquisition, they are compromised by low and inconsistent usage; male medical circumcision substantially reduces HIV transmission but uptake remains relatively low; ART during pregnancy, delivery and breastfeeding can virtually eliminate mother-to-child transmission but implementation is challenging, especially in resource-limited settings. The current HIV prevention recommendations focus on a combination of preventions approach, including ART as treatment or pre- or post-exposure prophylaxis together with condoms, circumcision and sexual behaviour modification. Improved survival in HIV-infected individuals and reduced HIV transmission risk is beginning to result in limited HIV incidence decline at population level and substantial increases in HIV prevalence. However, achievements in HIV treatment and prevention are threatened by the challenges of lifelong adherence to preventive and therapeutic methods and by the ageing of the HIV-infected cohorts potentially complicating HIV management. Although current thinking suggests prevention of HIV transmission through early detection of infection immediately followed by ART could eventually result in elimination of the HIV epidemic, controversies remain as to whether we can treat our way out of the HIV epidemic.
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Disengagement from care in a decentralised primary health care antiretroviral treatment programme: cohort study in rural South Africa.
Trop. Med. Int. Health
PUBLISHED: 06-03-2013
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To determine rates of, and factors associated with, disengagement from care in a decentralised antiretroviral programme.
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Health, wellbeing, and disability among older people infected or affected by HIV in Uganda and South Africa.
Glob Health Action
PUBLISHED: 02-01-2013
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To describe and compare the health status, emotional wellbeing, and functional status of older people in Uganda and South Africa who are HIV infected or affected by HIV in their families.
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CD4 count slope and mortality in HIV-infected patients on antiretroviral therapy: multicohort analysis from South Africa.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 01-25-2013
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In many resource-limited settings monitoring of combination antiretroviral therapy (cART) is based on the current CD4 count, with limited access to HIV RNA tests or laboratory diagnostics. We examined whether the CD4 count slope over 6 months could provide additional prognostic information.
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Decreased chronic morbidity but elevated HIV associated cytokine levels in HIV-infected older adults receiving HIV treatment: benefit of enhanced access to care?
PLoS ONE
PUBLISHED: 01-01-2013
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The association of HIV with chronic morbidity and inflammatory markers (cytokines) in older adults (50+years) is potentially relevant for clinical care, but data from African populations is scarce.
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A missing piece in the puzzle: HIV in mature adults in sub-Saharan Africa.
Future Virol
PUBLISHED: 11-17-2011
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Healthcare and social needs for mature adults aged 50 years or older differ from those of younger adults due to stigma concerning HIV in older people, beliefs that engagement in sexual activity no longer applies, age driven comorbidities and responses to antiretroviral treatment, which complicate HIV diagnosis and management. In the face of a growing HIV epidemic in mature adults, mostly due to infected people aging with HIV, but also due to new infections in this age group, HIV services, which mostly cater for HIV in young adults and children, and HIV education messages and interventions, which mainly target young adults, leave the mature adult exposed and vulnerable to HIV transmission and to a lack of care and treatment thereafter.
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Poor long-term outcomes for cryptococcal meningitis in rural South Africa.
S. Afr. Med. J.
PUBLISHED: 07-27-2011
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To explore linkage to and retention in HIV care after an episode of cryptococcal meningitis (CM) in rural South Africa. Design. A retrospective case series of adult individuals (> or = 16 years old) with laboratory-confirmed CM from January - December 2007 at Hlabisa Hospital--a district hospital in northern KwaZulu-Natal.
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Association of age with mortality and virological and immunological response to antiretroviral therapy in rural South African adults.
PLoS ONE
PUBLISHED: 06-11-2011
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To assess whether treatment outcomes vary with age for adults receiving antiretroviral therapy (ART) in a large rural HIV treatment cohort.
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Retention in HIV care for individuals not yet eligible for antiretroviral therapy: rural KwaZulu-Natal, South Africa.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 04-05-2011
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To determine retention in HIV care for individuals not yet eligible for antiretroviral therapy (ART) and to explore factors associated with retention in a rural public health HIV program.
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Scale-up of a decentralized HIV treatment programme in rural KwaZulu-Natal, South Africa: does rapid expansion affect patient outcomes?
Bull. World Health Organ.
PUBLISHED: 05-10-2010
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To describe the scale-up of a decentralized HIV treatment programme delivered through the primary health care system in rural KwaZulu-Natal, South Africa, and to assess trends in baseline characteristics and outcomes in the study population.
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The tuberculosis challenge in a rural South African HIV programme.
BMC Infect. Dis.
PUBLISHED: 02-10-2010
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South Africa remains the country with the greatest burden of HIV-infected individuals and the second highest estimated TB incidence per capita worldwide. Within South Africa, KwaZulu-Natal has one of the highest rates of TB incidence and an emerging epidemic of drug-resistant tuberculosis.
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Treatment of cryptococcal meningitis in KwaZulu-Natal, South Africa.
PLoS ONE
PUBLISHED: 01-07-2010
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Cryptococcal meningitis (CM) remains a leading cause of death for HIV-infected individuals in sub-Saharan Africa. Improved treatment strategies are needed if individuals are to benefit from the increasing availability of antiretroviral therapy. We investigated the factors associated with mortality in routine care in KwaZulu-Natal, South Africa.
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An investigation of factors associated with the health and well-being of HIV-infected or HIV-affected older people in rural South Africa.
BMC Public Health
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Despite the severe impact of HIV in sub-Saharan Africa, the health of older people aged 50+ is often overlooked owing to the dearth of data on the direct and indirect effects of HIV on older peoples health status and well-being. The aim of this study was to examine correlates of health and well-being of HIV-infected older people relative to HIV-affected people in rural South Africa, defined as participants with an HIV-infected or death of an adult child due to HIV-related cause.
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Reduction in early mortality on antiretroviral therapy for adults in rural South Africa since change in CD4+ cell count eligibility criteria.
J. Acquir. Immune Defic. Syndr.
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OBJECTIVE:: To explore the impact of expanded eligibility criteria for antiretroviral therapy (ART) on median CD4+ cell count at ART initiation and early mortality on ART. METHODS:: Analyses included all adults (?16 years) initiated on first-line ART between August 2004 and July 2012. CD4+ cell count threshold 350 cells/µL for all adults was implemented in August 2011. Early mortality was defined as any death within 91 days of ART initiation. Trends in baseline CD4+ cell count and early mortality were examined by year (August-July) of ART initiation. Competing-risks analysis was used to examine early mortality. RESULTS:: A total of 19 080 adults (67.6% female) initiated ART. Median CD4+ cell count at ART initiation was 110-120 cells/µL over the first six years, increasing marginally to 145 cells/µL in 2010/11 and more significantly to 199 cells/µL in 2011/12. Overall, there were 875 deaths within 91 days of ART initiation; early mortality rate 19.4 per 100 person-years (95% confidence interval (CI) 18.2-20.7). After adjustment for sex, age, baseline CD4+ cell count and concurrent TB, there was a 46% decrease in early mortality for those who initiated ART in 2011/12 compared to the reference period 2008/9 (sub-hazard ratio 0.54, 95% CI 0.41-0.71). CONCLUSIONS:: Since the expansion of eligibility criteria, there is evidence of earlier access to ART and a significant reduction in early mortality rates in this primary health care programme. These findings provide strong support for national ART policies and highlight the importance of earlier ART initiation for achieving reductions in HIV-related mortality.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.