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2.
BMJ Open ; 13(8): e062913, 2023 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-37558440

RESUMEN

OBJECTIVES: This descriptive study of registered trials aimed to identify large clinical trials on antidepressants for mental disorders: (1) to assess what proportion could be labelled as 'seeding trials' (trials for marketing purposes) and (2) to describe their methodological characteristics and outcomes. DESIGN: A search was conducted across all trials registered on ClinicalTrials.gov by drug name in March 2017. SETTING: All trials registered in the database of ClinicalTrials.gov were screened. Large registered studies were received and studies focusing prospectively on the effects of antidepressants in mental health disorders. Specific data items were extracted automatically, and subsequently inspected, corrected and completed by hand. PARTICIPANTS: Prospective studies were selected focusing on the effects of antidepressants in any mental health disorder with 800 participants or more planned for inclusion. MAIN OUTCOME MEASURES: Three members from the study team independently assessed the following 'seeding trial' characteristics in each registered study: a high level of involvement of the product manufacturer in the study design, in the data analysis and reporting of the study, an abnormally low ratio of patient numbers to study site, spin and/or omissions of clinically relevant findings in the abstracts, and conclusions that focused on secondary endpoints and surrogate markers. Secondary outcomes were the exploration of a functional outcome and suicidality. RESULTS: 31 trials were identified from clinical trials database. 18/31 were published (58%). 8 of these 18 (44%) studies were identified as possible seeding trials. 13/31 (42%) large trials planned to explore functioning and 5/31 (16%) suicidality. CONCLUSIONS: Large trials are rare in the field of antidepressant research. Some could be 'seeding trials'. Few explored suicidality. Identifying seeding trials from incomplete data entries in registries, especially when almost half of the studies were still unpublished, posed considerable challenges. The delay between our research and publication limits the strength of our conclusions. PROSPERO REGISTRATION NUMBER: CRD42017065591.


Asunto(s)
Trastorno Depresivo Mayor , Trastornos Mentales , Humanos , Estudios Prospectivos , Antidepresivos/uso terapéutico , Trastornos Mentales/tratamiento farmacológico , Trastorno Depresivo Mayor/tratamiento farmacológico , Ideación Suicida
3.
BMJ Evid Based Med ; 27(3): 133-136, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-33785512

RESUMEN

During the COVID-19 pandemic, the rush to scientific and political judgements on the merits of hydroxychloroquine was fuelled by dubious papers which may have been published because the authors were not independent from the practices of the journals in which they appeared. This example leads us to consider a new type of illegitimate publishing entity, 'self-promotion journals' which could be deployed to serve the instrumentalisation of productivity-based metrics, with a ripple effect on decisions about promotion, tenure and grant funding, but also on the quality of manuscripts that are disseminated to the medical community and form the foundation of evidence-based medicine.


Asunto(s)
COVID-19 , Enfermedades Transmisibles , Humanos , Pandemias
4.
Transl Psychiatry ; 11(1): 314, 2021 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-34031363

RESUMEN

Though a plethora of functional magnetic resonance imaging (fMRI) studies explored the neurobiological underpinnings of borderline personality disorder (BPD), findings across different tasks were divergent. We conducted a systematic review and activation likelihood estimation (ALE) meta-analysis on the fMRI studies conducted in BPD patients compared to healthy controls (HC). We systematically searched PubMed and PsychINFO from inception until July 9th 2020 using combinations of database-specific terms like 'fMRI', 'Neuroimaging', 'borderline'. Eligible studies employed task-based fMRI of the brain in participants of any age diagnosed with BPD compared to HC, during any behavioral task and providing a direct contrast between the groups. From 762 entries, we inspected 92 reports full-texts and included 52 studies (describing 54 experiments). Across all experiments, the HC > BPD and BPD > HC meta-analyses did not yield any cluster of significant convergence of differences. Analyses restricted to studies of emotion processing revealed two significant clusters of activation in the bilateral hippocampal/amygdala complex and anterior cingulate for the BPD > HC meta-analysis. Fail-safe N and single study sensitivity analysis suggested significant findings were not robust. For the subgroup of emotional processing experiments, on a restricted number of experiments providing results for each group separately, another meta-analysis method (difference of convergence) showed a significant cluster in the insula/inferior frontal gyrus for the HC > BPD contrast. No consistent pattern of alteration in brain activity for BPD was evidenced suggesting substantial heterogeneity of processes and populations studied. A pattern of amygdala dysfunction emerged across emotion processing tasks, indicating a potential pathophysiological mechanism that could be transdiagnostic.


Asunto(s)
Trastorno de Personalidad Limítrofe , Amígdala del Cerebelo/diagnóstico por imagen , Trastorno de Personalidad Limítrofe/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Emociones , Humanos , Imagen por Resonancia Magnética , Neuroimagen
5.
JAMA Pediatr ; 175(6): 643-644, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33646294
6.
J Child Psychol Psychiatry ; 62(12): 1412-1424, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33723876

RESUMEN

BACKGROUND: Though aberrant face processing is a hallmark of autistic spectrum disorder (ASD), findings on accompanying brain activity are divergent. Therefore, we conducted an activation likelihood estimation (ALE) meta-analysis of studies examining brain activity during face processing. METHODS: We searched PubMed and PsycINFO using combinations of terms as 'fMRI', 'Autism Spectrum Disorder', 'Face Perception'. Eligible studies reported on DSM-diagnosed ASD individuals, compared to controls (HC), using face stimuli presented in fMRI and reporting whole-brain analysis coordinates. We compared two approaches: 'convergence of differences' (primary analysis) using study-level coordinates from ASD vs. HC contrasts, and 'differences in convergence' (secondary) pooling coordinates within each group separately, and contrasting the resultant ALE maps. RESULTS: Thirty-five studies (655 ASD and 668 HC) were included. Primary analysis identified a cluster in amygdala/parahippocampus where HC showed greater convergence of activation. Secondary analysis yielded no significant results. CONCLUSIONS: Results suggest that ASD dysfunction in face processing relies on structures involved in emotional processing rather than perception. We also demonstrate that the two ALE methodologies lead to divergent results.


Asunto(s)
Trastorno del Espectro Autista , Trastorno del Espectro Autista/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Humanos , Funciones de Verosimilitud , Imagen por Resonancia Magnética , Neuroimagen
8.
Epidemiol Psychiatr Sci ; 29: e184, 2020 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-33109299

RESUMEN

In the coronavirus disease 2019 (COVID-19) pandemic, a large number of non-pharmaceutical measures that pertain to the wider group of social distancing interventions (e.g. public gathering bans, closures of schools, workplaces and all but essential business, mandatory stay-at-home policies, travel restrictions, border closures and others) have been deployed. Their urgent deployment was defended with modelling and observational data of spurious credibility. There is major debate on whether these measures are effective and there is also uncertainty about the magnitude of the harms that these measures might induce. Given that there is equipoise for how, when and if specific social distancing interventions for COVID-19 should be applied and removed/modified during reopening, we argue that informative randomised-controlled trials are needed. Only a few such randomised trials have already been conducted, but the ones done to-date demonstrate that a randomised trials agenda is feasible. We discuss here issues of study design choice, selection of comparators (intervention and controls), choice of outcomes and additional considerations for the conduct of such trials. We also discuss and refute common counter-arguments against the conduct of such trials.


Asunto(s)
Coronavirus , Pandemias , Distancia Psicológica , Ensayos Clínicos Controlados Aleatorios como Asunto , Equipoise Terapéutico , Betacoronavirus , COVID-19 , Infecciones por Coronavirus/epidemiología , Humanos , Neumonía Viral/epidemiología , Proyectos de Investigación , SARS-CoV-2 , Condiciones Sociales
9.
PLoS One ; 15(7): e0234612, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32726312

RESUMEN

We aimed to assess whether Nobel prizes (widely considered the most prestigious award in science) are clustering in work done in a few specific disciplines. We mapped the key Nobel prize-related publication of each laureate awarded the Nobel Prize in Medicine, Physics, and Chemistry (1995-2017). These key papers mapped in only narrow sub-regions of a 91,726-cluster map of science created from 63 million Scopus-indexed published items. For each key Nobel paper, a median of 435 (range 0 to 88383) other Scopus-indexed items were published within one year and were more heavily cited than the Nobel paper. Of the 114 high-level domains that science can be divided into, only 36 have had a Nobel prize. Five of the 114 domains (particle physics [14%], cell biology [12.1%], atomic physics [10.9%], neuroscience [10.1%], molecular chemistry [5.3%]) have the lion's share, accounting in total for 52.4% of the Nobel prizes. Using a more granular classification with 849 sub-domains shows that only 71 of these sub-domains (8.3%) have at least one Nobel-related paper. Similar clustering was seen when we mapped all the 40,819 Scopus-indexed publications representing the career-long output of all the Nobel laureates. In conclusion, work resulting in Nobel prizes is concentrated in a small minority of scientific disciplines.


Asunto(s)
Premio Nobel , Ciencia/historia , Distinciones y Premios , Bibliometría/historia , Química/historia , Historia de la Medicina , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Medicina , Física/historia
10.
BMJ Evid Based Med ; 24(6): 231-238, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31320322

RESUMEN

BACKGROUND: In November 2017, the Food and Drug Administration (FDA) approved a version of a second-generation antipsychotic, aripiprazole, embedded with a sensor (Abilify MyCite). OBJECTIVE: To systematically review the evidence supporting the FDA's approval of digital aripiprazole and how that evidence was disseminated in the scientific literature and news reports. STUDY SELECTION: Prospective, double-blind, randomised controlled trials (RCTs), non-randomised and non-comparative studies were included if they focused on the use of digital aripiprazole. All scientific publications citing the trials were included if written in English. For the news reports, all languages were included if an English translation was available, and all records that were published after FDA approval were included. FINDINGS: In the primary evidence search, no RCT comparing digital aripiprazole with a non-digital formulation, other active comparators or placebo was found. Only three non-comparative uncontrolled cohorts were found. No study provided data on remission, quality of life or any efficacy outcome. Fourteen scientific papers were identified that cited the trials and 70 news stories met the inclusion criteria. Almost 80% (11/14) of the scientific papers and three-fourths (52/70) of the news stories conveyed an unsupported impression of benefit. CONCLUSIONS: Regulatory approval for this first-ever digital drug was based on weak evidence, and there was no evidence of better adherence with the digital version of aripiprazole compared with the non-digital version. The possibilities afforded by this technology make room for a new type of evergreening (ie, patenting of older drugs with a sensor as a 'new invention'). Both the scientific literature and news reports conveyed an unsupported impression of benefit. TRIAL REGISTRATION NUMBER: CRD42018089515.


Asunto(s)
Antipsicóticos/administración & dosificación , Aripiprazol/administración & dosificación , Técnicas Biosensibles/métodos , Difusión de la Información/métodos , Cumplimiento de la Medicación , Edición/normas , Comunicación Académica/normas , Técnicas Biosensibles/instrumentación , Aprobación de Drogas , Humanos , Patentes como Asunto , Estados Unidos , United States Food and Drug Administration
11.
BMJ Open ; 9(2): e024622, 2019 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-30782912

RESUMEN

INTRODUCTION: One potential source of bias in randomised clinical trials of psychological interventions is researcher allegiance (RA). The operationalisation of RA differs strongly across studies, and there is not a generally accepted method of operationalising or measuring it. Furthermore, it remains unclear as to how RA affects the outcomes of trials and if it results in better outcomes for a preferred intervention. The aim of this project is to develop and validate a scale that accurately identifies RA, contribute to the understanding of the impact that RA has in a research setting and to make recommendations for addressing RA in practice. METHODS AND ANALYSIS: A scale will first be developed and validated to measure RA in psychotherapy trials. The scale will be validated by surveying authors of psychotherapy trials to assess their opinions, beliefs and preferences of psychotherapy interventions. Furthermore, the scale will be validated for use outside the field of psychotherapy. The validated checklist will then be used to examine two potential mechanisms of how RA may affect outcomes of interventions: publication bias (by assessing grants) and risk of bias (RoB). Finally, recommendations will be developed, and a feasibility study will be conducted at a national mental health agency in The Netherlands. Main analyses comprise inter-rater reliability of checklist items, correlations to examine the relationship between checklist items and author survey (convergent validity) as well as checklist items and trial outcomes and multivariate meta-regression techniques to assess potential mechanisms of how allegiance affects trial outcomes (publication bias and RoB). ETHICS AND DISSEMINATION: This study has been reviewed and approved by the Scientific and Ethical Review Board (VCWE) at the Vrije Universiteit Amsterdam. Study result and advancements will also be published on the Open Science Framework. Furthermore, main findings will be disseminated through articles in international peer-reviewed open access journals. Results and recommendations will be communicated to the Cochrane Collaboration, the Campbell Collaboration and other funding agencies.


Asunto(s)
Evaluación de Resultado en la Atención de Salud , Psicoterapia , Sesgo de Publicación , Investigadores/ética , Lista de Verificación , Humanos , Metaanálisis como Asunto , Análisis Multivariante , Países Bajos , Proyectos Piloto , Ensayos Clínicos Controlados Aleatorios como Asunto , Análisis de Regresión , Proyectos de Investigación
13.
Intensive Care Med ; 44(12): 2323, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30406805

RESUMEN

The original article can be found online.

14.
JAMA Psychiatry ; 75(12): 1303-1304, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30285040
16.
PLoS One ; 13(5): e0197440, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29763472

RESUMEN

P values represent a widely used, but pervasively misunderstood and fiercely contested method of scientific inference. Display items, such as figures and tables, often containing the main results, are an important source of P values. We conducted a survey comparing the overall use of P values and the occurrence of significant P values in display items of a sample of articles in the three top multidisciplinary journals (Nature, Science, PNAS) in 2017 and, respectively, in 1997. We also examined the reporting of multiplicity corrections and its potential influence on the proportion of statistically significant P values. Our findings demonstrated substantial and growing reliance on P values in display items, with increases of 2.5 to 14.5 times in 2017 compared to 1997. The overwhelming majority of P values (94%, 95% confidence interval [CI] 92% to 96%) were statistically significant. Methods to adjust for multiplicity were almost non-existent in 1997, but reported in many articles relying on P values in 2017 (Nature 68%, Science 48%, PNAS 38%). In their absence, almost all reported P values were statistically significant (98%, 95% CI 96% to 99%). Conversely, when any multiplicity corrections were described, 88% (95% CI 82% to 93%) of reported P values were statistically significant. Use of Bayesian methods was scant (2.5%) and rarely (0.7%) articles relied exclusively on Bayesian statistics. Overall, wider appreciation of the need for multiplicity corrections is a welcome evolution, but the rapid growth of reliance on P values and implausibly high rates of reported statistical significance are worrisome.


Asunto(s)
Edición/estadística & datos numéricos , Ciencia/estadística & datos numéricos , Teorema de Bayes , Biometría , Encuestas y Cuestionarios
18.
Br J Psychiatry ; 212(4): 247, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-30741138
20.
Behav Brain Res ; 327: 34-43, 2017 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-28342970

RESUMEN

INTRODUCTION: Neuroticism is a complex personality trait encompassing diverse aspects. Notably, high levels of neuroticism are related to the onset of psychiatric conditions, including anxiety and mood disorders. Personality traits are stable individual features; therefore, they can be expected to be associated with stable neurobiological features, including the Brain Resting State (RS) activity as measured by fMRI. Several metrics have been used to describe RS properties, yielding rather inconsistent results. This inconsistency could be due to the fact that different metrics portray different RS signal properties and that these properties may be differently affected by neuroticism. To explore the distinct effects of neuroticism, we assessed several distinct metrics portraying different RS properties within the same population. METHOD: Neuroticism was measured in 31 healthy subjects using the Zuckerman-Kuhlman Personality Questionnaire; RS was acquired by high-resolution fMRI. Using linear regression, we examined the modulatory effects of neuroticism on RS activity, as quantified by the Amplitude of low frequency fluctuations (ALFF, fALFF), regional homogeneity (REHO), Hurst Exponent (H), global connectivity (GC) and amygdalae functional connectivity. RESULTS: Neuroticism modulated the different metrics across a wide network of brain regions, including emotional regulatory, default mode and visual networks. Except for some similarities in key brain regions for emotional expression and regulation, neuroticism affected different metrics in different ways. DISCUSSION: Metrics more related to the measurement of regional intrinsic brain activity (fALFF, ALFF and REHO), or that provide a parsimonious index of integrated and segregated brain activity (HE), were more broadly modulated in regions related to emotions and their regulation. Metrics related to connectivity were modulated across a wider network of areas. Overall, these results show that neuroticism affects distinct aspects of brain resting state activity. More in general, these findings indicate that a multiparametric approach may be required to obtain a more detailed characterization of the neural underpinnings of a given psychological trait.


Asunto(s)
Encéfalo/fisiología , Neuroticismo/fisiología , Adulto , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Femenino , Humanos , Modelos Lineales , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiología , Pruebas de Personalidad , Descanso , Encuestas y Cuestionarios
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