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Find video protocols related to scientific articles indexed in Pubmed.
Ensemble learning of inverse probability weights for marginal structural modeling in large observational datasets.
Stat Med
PUBLISHED: 09-17-2014
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Inverse probability weights used to fit marginal structural models are typically estimated using logistic regression. However, a data-adaptive procedure may be able to better exploit information available in measured covariates. By combining predictions from multiple algorithms, ensemble learning offers an alternative to logistic regression modeling to further reduce bias in estimated marginal structural model parameters. We describe the application of two ensemble learning approaches to estimating stabilized weights: super learning (SL), an ensemble machine learning approach that relies on V-fold cross validation, and an ensemble learner (EL) that creates a single partition of the data into training and validation sets. Longitudinal data from two multicenter cohort studies in Spain (CoRIS and CoRIS-MD) were analyzed to estimate the mortality hazard ratio for initiation versus no initiation of combined antiretroviral therapy among HIV positive subjects. Both ensemble approaches produced hazard ratio estimates further away from the null, and with tighter confidence intervals, than logistic regression modeling. Computation time for EL was less than half that of SL. We conclude that ensemble learning using a library of diverse candidate algorithms offers an alternative to parametric modeling of inverse probability weights when fitting marginal structural models. With large datasets, EL provides a rich search over the solution space in less time than SL with comparable results. Copyright © 2014 John Wiley & Sons, Ltd.
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Mortality in patients with HIV-1 infection starting antiretroviral therapy in South Africa, Europe, or North America: a collaborative analysis of prospective studies.
PLoS Med.
PUBLISHED: 09-01-2014
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High early mortality in patients with HIV-1 starting antiretroviral therapy (ART) in sub-Saharan Africa, compared to Europe and North America, is well documented. Longer-term comparisons between settings have been limited by poor ascertainment of mortality in high burden African settings. This study aimed to compare mortality up to four years on ART between South Africa, Europe, and North America.
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Pattern of neurocognitive function in patients receiving boosted protease inhibitor monotherapy: a detailed neuropsychological study.
J. Neurovirol.
PUBLISHED: 03-26-2014
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It is unknown if, compared to a triple drug antiretroviral therapy, boosted protease inhibitor monotherapy leads to worse results in specific neuropsychological processes. In our study, we included patients virologically suppressed (?1 year), on antiretroviral therapy, without concomitant major neurocognitive confounders, receiving boosted lopinavir or darunavir as monotherapy (n = 96) or as triple therapy with two nucleoside reverse transcriptase inhibitors (n = 95). All patients underwent a comprehensive neuropsychological test battery (14 neuropsychological measures, covering seven domains). Both groups were compared in average score distributions and rates of neuropsychological deficits. Similar comparisons were conducted only for patients with neurocognitive impairment. In the adjusted analysis, we found only small differences between groups in the entire sample: better verbal learning (p = 0.02; d = 0.28) and verbal recall scores (p < 0.01; d = 0.25) in patients on boosted protease inhibitor monotherapy and slightly better motor skills with dominant hand (p = 0.02; d = 0.23) scores in patients on triple therapy. No greater proportion of deficits in the protease inhibitor monotherapy group was found in any neuropsychological measure. In neurocognitively impaired patients, we found similar outcomes in verbal learning, verbal recall, and motor skills with dominant hand but with larger effect sizes. Close similarities in the neurocognitive pattern between groups question the clinical relevance of the number of neuroactive drugs included in the regimen. These results also suggest that peripheral viral load control may be a good indicator of brain protection.
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Cerebral volumes, neuronal integrity and brain inflammation measured by MRI in patients receiving PI monotherapy or triple therapy.
J Int AIDS Soc
PUBLISHED: 01-01-2014
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Penetration of protease inhibitors (PI) in the central nervous system (CNS) is limited. Therefore, there are concerns about the capacity of PI monotherapy (MT) to control HIV in CNS and preserve brain integrity.
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Comparison of oxidative stress markers in HIV-infected patients on efavirenz or atazanavir/ritonavir-based therapy.
J Int AIDS Soc
PUBLISHED: 01-01-2014
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Chronic low-grade inflammation and immune activation may persist in HIV patients despite effective antiretroviral therapy (ART). These abnormalities are associated with increased oxidative stress (OS). Bilirubin (BR) may have a beneficial role in counteracting OS. Atazanavir (ATV) inhibits UGT1A1, thus increasing unconjugated BR levels, a distinctive feature of this drug. We compared changes in OS markers in HIV patients on ATV/r versus efavirenz (EFV)-based first-line therapies.
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Clinically relevant transmitted drug resistance to first line antiretroviral drugs and implications for recommendations.
PLoS ONE
PUBLISHED: 01-01-2014
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The aim was to analyse trends in clinically relevant resistance to first-line antiretroviral drugs in Spain, applying the Stanford algorithm, and to compare these results with reported Transmitted Drug Resistance (TDR) defined by the 2009 update of the WHO SDRM list.
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HIV testing policies for migrants and ethnic minorities in EU/EFTA Member States.
Eur J Public Health
PUBLISHED: 08-05-2013
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In the context of an European Centre for Disease Prevention and Control (ECDC) research project, our objective was to describe current recommendations regarding HIV testing and counselling targeting migrants and ethnic minorities in the European Union/European Economic Area/European Free Trade Association (EU/EEA/EFTA) Member States.
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All-cause mortality in the cohorts of the Spanish AIDS Research Network (RIS) compared with the general population: 1997-2010.
BMC Infect. Dis.
PUBLISHED: 02-19-2013
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Combination antiretroviral therapy (cART) has produced significant changes in mortality of HIV-infected persons. Our objective was to estimate mortality rates, standardized mortality ratios and excess mortality rates of cohorts of the AIDS Research Network (RIS) (CoRIS-MD and CoRIS) compared to the general population.
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Neurocognitive impairment in patients treated with protease inhibitor monotherapy or triple drug antiretroviral therapy.
PLoS ONE
PUBLISHED: 01-01-2013
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In patients who remain virologically suppressed in plasma with triple-drug ART a switch to protease inhibitor monotherapy maintains high rates of suppression; however it is unknown if protease inhibitor monotherapy is associated to a higher rate of neurocognitive impairment.
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Educational level and HIV disease progression before and after the introduction of HAART: a cohort study in 989 HIV seroconverters in Spain.
Sex Transm Infect
PUBLISHED: 10-03-2011
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To analyse the effect of educational level on the progression from HIV seroconversion to highly active antiretroviral therapy (HAART) requirement, HAART initiation, AIDS and death from any cause at different periods of the HIV epidemic in Spain.
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[Socio-demographic factors associated with the progression of HIV infection and the impact of HAART in a seroconverter cohort in Madrid (1986-2009)].
Enferm. Infecc. Microbiol. Clin.
PUBLISHED: 04-13-2011
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The objective of this work is to study the impact of HAART at a population level and to identify socio-demographic factors that may affect it, which is essential for deciding interventions.
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[Analysis of complaints in primary care using statistical process control].
Rev Calid Asist
PUBLISHED: 01-20-2009
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To analyze patient complaints in a Primary Health Care District (PHCD) using statistical process control methods compared to multivariate methods, as regards their results and feasibility of application in this context.
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HIV testing and counselling for migrant populations living in high-income countries: a systematic review.
Eur J Public Health
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The barriers to HIV testing and counselling that migrants encounter can jeopardize proactive HIV testing that relies on the fact that HIV testing must be linked to care. We analyse available evidence on HIV testing and counselling strategies targeting migrants and ethnic minorities in high-income countries.
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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.