Timing of multivessel revascularization in stable patients with STEMI: a systematic review and network meta-analysis.

INTRODUCTION AND OBJECTIVES: Multivessel percutaneous coronary intervention (MV-PCI) is recommended in patients with ST-segment elevation myocardial infarction (STEMI) and multivessel coronary artery disease (CAD) without cardiogenic shock. The present network meta-analysis investigated the optimal timing of MV-PCI in this context. METHODS: We pooled the aggregated data from randomized trials investigating stable STEMI patients with multivessel cad treated with a strategy of either MV-PCI or culprit vessel-only PCI. The primary outcome was all-cause death. The main secondary outcomes were cardiovascular death, myocardial infarction, and unplanned ischemia-driven revascularization. This study is registered at PROSPERO (CRD42023457794). RESULTS: Among 11 trials, a total of 10 507 patients were randomly assigned to MV-PCI (same sitting, n = 1683; staged during the index hospitalization, n = 3460; staged during a subsequent hospitalization within 45 days, n = 3275) or to culprit vessel-only PCI (n = 2089). The median follow-up was 18.6 months. In comparison with culprit vessel-only PCI, MV-PCI staged during the index hospitalization significantly reduced all-cause death (risk ratio, 0.73; 95%CI, 0.56-0.92; P = .008) and ranked as possibly the best treatment option for this outcome compared with all other strategies. In comparison with culprit vessel-only PCI, a MV-PCI reduced cardiovascular mortality without differences dependent on the timing of revascularization. MV-PCI within the index hospitalization, either in a single procedure or staged, significantly reduced myocardial infarction and unplanned ischemia-driven revascularization, with no significant difference between each other. CONCLUSIONS: In patients with STEMI and multivessel CAD without cardiogenic shock, multivessel PCI within the index hospitalization, either in a single procedure or staged, represents the safest and most efficacious approach. The different timings of multivessel PCI did not result in any significant differences in all-cause death.

Emotional Regulation as a Transdiagnostic Process of Emotional Disorders in Therapy: A Systematic Review and Meta-Analysis.

CONTEXT: Several studies have shown that emotional regulation (ER) is a transdiagnostic construct of emotional disorders. Therefore, if therapy improves ER, it would improve psychological distress. OBJECTIVE: This review assesses and compares the changes in ER due to psychological treatment in different therapies. METHODS: A systematic review and meta-analysis of RCTs published in the databases PubMed, PsycINFO and Web of Science was performed. It was registered in PROSPERO under the number CRD42023387317. Two independent experts in the field reviewed the articles. RESULTS: A total of 18 articles met the criteria for inclusion in the review. Analysis of these studies suggests that in unified protocol (UP), cognitive behaviour therapy, dialectical behaviour therapy (DBT) and mindfulness, there is evidence to support that a moderate effect occurs during treatment. Furthermore, in mindfulness and DBT, the effect was moderate in the follow-up period, while in UP, it was high. LIMITATIONS: Given the heterogeneity of the applied interventions and the methodological limitations found in the reviewed trials, the results should be interpreted with caution. CONCLUSIONS: UP, cognitive behaviour therapy, DBT and mindfulness can improve ER after therapy, while UP, DBT and mindfulness in the follow-up period. Other therapies, such as SKY or Flotation REST, require more research.

INTRODUCCIÓN: Varios estudios han demostrado que la regulación emocional es un constructo transdiagnóstico de los trastornos emocionales. Por lo tanto, si la terapia mejora la regulación emocional, también mejorará el malestar psicológico. OBJETIVO: Evaluar y comparar el cambio en la regulación emocional debido al tratamiento psicológico en diferentes terapias. MÉTODO: Se realizó una revisión sistemática y metaanálisis de ECA publicados en las bases de datos PubMed, PsycINFO y Web of Science. Se registró en PROSPERO con el número CRD42023387317. Dos expertos independientes en la materia revisaron los artículos. RESULTADOS: Un total de 18 artículos cumplieron los criterios de inclusión en la revisión. El análisis de estos estudios sugiere que en el Protocolo Unificado, la Terapia Cognitivo Conductual, la Terapia Dialéctica Conductual y terapias basadas en mindfulness existen evidencias que apoyan que se produce un efecto moderado durante el tratamiento. Además, en las terapias basadas en mindfulness y en la Terapia Dialéctica Conductual, el efecto se moduló en el periodo de seguimiento, mientras que en el Protocolo Unificado fue mayor. LIMITACIONES: Dada la heterogeneidad de las intervenciones aplicadas y las limitaciones metodológicas encontradas en los ensayos revisados, los resultados podrán interpretarse con cautela. CONCLUSIONES: UP, CBT, DBT y mindfulness pueden mejorar la ER tras la terapia, mientras que UP, DBT y mindfulness pueden mejorar la recuperación tras un tiempo de seguimiento. Otras terapias, como SKY o Flotation REST, requieren más investigación.

Resultados tras 5 años de cirugía o abordaje percutáneo en coronariopatía grave. Metanálisis de ensayos aleatorizados con reconstrucción del tiempo hasta el evento / Results beyond 5-years of surgery or percutaneous approach in severe coronary disease. Reconstructed time-to-event meta-analysis of randomized trials

Introducción y objetivos: Existe controversia sobre la mejor estrategia de revascularización en la enfermedad coronaria avanzada, incluidas la enfermedad del tronco coronario y la enfermedad multivaso. Varios metanálisis han comparado resultados a 5 años, pero no hay resultados después del quinto año. Se realizaron una revisión sistemática y un metanálisis de ensayos clínicos aleatorizados para comparar los resultados después del quinto año entre la cirugía de revascularización coronaria (CABG) y la intervención coronaria percutánea (ICP) con stents farmacoactivos.MétodosSe analizaron los ensayos clínicos publicados entre 2010 y 2023. El objetivo primario fue la mortalidad por cualquier causa. Las bases de datos originales se reconstruyeron a partir de las curvas de Kaplan-Meier simulando un metanálisis individual. Se realizaron comparaciones en ciertos puntos de corte (5 y 10 años). Se calculó la diferencia del tiempo medio de supervivencia restringida. Se aplicó el modelo de efectos aleatorios y de DerSimonian-Laird.ResultadosSe analizó a 5.180 pacientes. Durante los 10 años de seguimiento, las ICP muestran una mayor incidencia de mortalidad (HR=1,19; IC95%, 1,04-1,32; p=0,008). La ICP muestra un mayor riesgo de mortalidad a 5 años (HR=1,2; IC95%, 1,06-1,53; p=0,008), mientras que no hubo diferencias de 5 a 10 años (HR=1,03; IC95%, 0,84-1,26; p=0,76). La esperanza de vida de los pacientes sometidos a CABG fue ligeramente mayor (2,4 meses más).ConclusionesEntre los pacientes con enfermedad coronaria avanzada, incluidas la enfermedad del tronco coronario y la enfermedad multivaso, hubo mayor mortalidad tras una ICP que tras la CABG a los 10 años de seguimiento. En concreto, la ICP tiene mayor mortalidad durante los primeros 5 años y un riesgo comparable de 5 a 10 años. (AU)

Introduction and objectives: There is controversy about the optimal revascularization strategy in severe coronary artery disease (CAD), including left main disease and/or multivessel disease. Several meta-analyses have analyzed the results at 5-year follow-up but there are no results after the fifth year. We conducted a systematic review and meta-analysis of randomized clinical trials, comparing results after the fifth year, between coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) using drug-eluting stents in patients with severe CAD.MethodsWe analyzed all clinical trials between January 2010 and January 2023. The primary endpoint was all-cause mortality. The databases of the original articles were reconstructed from Kaplan-Meier curves, simulating an individual-level meta-analysis. Comparisons were made at certain cutoff points (5 and 10 years). The 10-year restricted median survival time difference between CABG and PCI was calculated. The random effects model and the DerSimonian-Laird method were applied.ResultsThe meta-analysis included 5180 patients. During the 10-year follow-up, PCI showed a higher overall incidence of all-cause mortality (HR, 1.19; 95%CI, 1.04-1.32; P=.008)]. PCI showed an increased risk of all-cause mortality within 5 years (HR, 1.2; 95%CI, 1.06-1.53; P=.008), while no differences in the 5–10-year period were revealed (HR, 1.03; 95%CI, 0.84-1.26; P=.76). Life expectancy of CABG patients was slightly higher than that of PCI patients (2.4 months more).ConclusionsIn patients with severe CAD, including left main disease and/or multivessel disease, there was higher a incidence of all-cause mortality after PCI compared with CABG at 10 years of follow-up. Specifically, PCI has higher mortality during the first 5 years and comparable risk beyond 5 years. (AU)

The association of cadmium heavy metal with growth failure in children: A systematic review and meta-analysis.

Introduction: Introduction: early exposure to cadmium toxic metal has been suggested to be associated with reduced infants/children growth; nevertheless, the available evidence is contradictory. Objective: this meta-analysis aimed to examine the association of cadmium exposure through biological samples to growth measurements of infants/children, including body weight, height, body mass index (BMI), BMI-for-age (BMI Z-score), weight-for-age (WAZ), height-for-age (HAZ), and weight-for-height (WHZ) z-scores. Methods: a systematic search in PubMed and Scopus was implemented to obtain the related studies. The standardized beta coefficients (ß) and 95 % confidence intervals (95 % CI) were used as effect sizes to test the associations using the random effects analysis. Results: a total of 15 studies with 6,181 participants were included in the meta-analysis. In the overall analysis, pooled analysis of available data revealed that cadmium exposure was inversely linked to height (ß = -0.06, 95 % CI = -0.12 to -0.01) and WAZ (ß = -0.01, 95 % CI = -0.02 to -0.003). These relationships were also supported by prospective cohort studies and urinary cadmium exposure. In the stratified analysis, cadmium exposure was negatively linked to the weight of children in prospective cohort studies, in studies that assessed urinary cadmium exposure. No significant association was detected between cadmium exposure and BMI, BMI Z-score, WHZ, and HAZ in the overall and subgroup analyses. Conclusions: this meta-analysis emphasized the importance of cadmium exposure as a risk factor for growth failure in infants/children.

Introducción: Introducción: se ha sugerido que la exposición temprana al metal tóxico cadmio se asocia a un crecimiento reducido de los bebés y niños; sin embargo, la evidencia disponible es contradictoria. Objetivo: este metanálisis tuvo como objetivo examinar la asociación de la exposición al cadmio a través de muestras biológicas con las mediciones de crecimiento de bebés/niños, incluidos el peso corporal, la altura, el índice de masa corporal (IMC), el IMC para la edad (puntuación Z del IMC) y las puntuaciones z de peso para la edad (WAZ), altura para la edad (HAZ) y peso para la altura (WHZ). Métodos: se implementó una búsqueda sistemática en PubMed y Scopus para obtener los estudios relacionados. Los coeficientes beta estandarizados (ß) y los intervalos de confianza del 95 % (IC 95 %) se utilizaron como tamaños del efecto para probar las asociaciones mediante el análisis de efectos aleatorios. Resultados: se incluyeron en el metanálisis un total de 15 estudios, con 6.181 participantes. En el análisis general, el análisis conjunto de los datos disponibles reveló que la exposición al cadmio estaba inversamente relacionada con la altura (ß = -0,06, IC del 95 % = -0,12 a -0,01) y WAZ (ß = -0,01, IC del 95 % = -0,02 a -0,003). Estas relaciones también fueron respaldadas por estudios de cohortes prospectivos y exposición al cadmio en orina. En el análisis estratificado, la exposición al cadmio se relacionó negativamente con el peso de los niños en estudios de cohortes prospectivos, en estudios que evaluaron la exposición al cadmio en la orina. No se detectó ninguna asociación significativa entre la exposición al cadmio y el IMC, la puntuación Z del IMC, el WHZ y el HAZ en los análisis generales y de subgrupos. Conclusiones: este metanálisis enfatizó la importancia de la exposición al cadmio como factor de riesgo del retraso del crecimiento en lactantes/niños.

So how special is special K? A systematic review and meta-analysis of ketamine for PTSD RCTs.

Background: PTSD is a significant mental health problem worldwide. Current evidence-based interventions suffer various limitations. Ketamine is a novel agent that is hoped to be incrementally better than extant interventions.Objective: Several randomized control trials (RCTs) of ketamine interventions for PTSD have now been published. We sought to systematically review and meta-analyse results from these trials to evaluate preliminary evidence for ketamine's incremental benefit above-and-beyond control interventions in PTSD treatment.Results: Omnibus findings from 52 effect sizes extracted across six studies (n = 221) yielded a small advantage for ketamine over control conditions at reducing PTSD symptoms (g = 0.27, 95% CI = 0.03, 0.51). However, bias-correction estimates attenuated this effect (adjusted g = 0.20, 95%, CI = -0.08, 0.48). Bias estimates indicated smaller studies reported larger effect sizes favouring ketamine. The only consistent timepoint assessed across RCTs was 24-hours post-initial infusion. Effects at 24-hours post-initial infusion suggest ketamine has a small relative advantage over controls (g = 0.35, 95% CI = 0.06, 0.64). Post-hoc analyses at 24-hours post-initial infusion indicated that ketamine was significantly better than passive controls (g = 0.44, 95% CI = 0.03, 0.85), but not active controls (g = 0.24, 95% CI = -0.30, 0.78). Comparisons one-week into intervention suggested no meaningful group differences (g = 0.24, 95% CI = 0.00, 0.48). No significant differences were evident for RCTs that examined effects two-weeks post initial infusion (g = 0.17, 95% CI = -0.10, 0.44).Conclusions: Altogether, ketamine-for-PTSD RCTs reveal a nominal initial therapeutic advantage relative to controls. However, bias and heterogeneity appear problematic. While rapid acting effects were observed, all control agents (including saline) also evidenced rapid acting effects. We argue blind penetration to be a serious concern, and that placebo is the likely mechanism behind reported therapeutic effects.

We systematically reviewed and meta-analysed all randomized control trials of ketamine intervention for PTSD.While ketamine was associated with a reduction in symptoms, the effect was generally not stronger than control conditions.By two-weeks post-initial infusion, no meaningful differences are evident between ketamine and controls.

El efecto de la reflexología podal sobre la fatiga en pacientes en hemodiálisis: un estudio de metaanálisis / The effect of foot reflexology on fatigue in hemodialysis patients: a meta-analysis study / O efeito da reflexologia podal sobre a fadiga em pacientes em hemodiálise: um estudo de metanálise

Objetivo: analizar el efecto de la reflexología podal sobre la fatiga en pacientes en hemodiálisis, combinando los resultados de estudios independientes sobre este tema. Método: estudio de metaanálisis. Se realizó una búsqueda bibliográfica en siete bases de datos. La calidad metodológica de los estudios incluidos se evaluó mediante las herramientas propuestas por el Joanna Briggs Institute. Para el metaanálisis se utilizó el programa Comprehensive Meta-Analysis v3. Resultados: en el metaanálisis se incluyeron ocho estudios. El resultado de la diferencia de medias estandarizada del metaanálisis = 1,580 (Intervalo de Confianza de 95% = 1,075 - 2,085 p = 0,000). El resultado del análisis de subgrupos realizado sobre la base de la diferencia de medias estandarizada en el número de sesiones de reflexología podal = 1,478 (Intervalo de Confianza de 95% = 1,210 - 1,747, p = 0,000). Conclusión: se concluyó que la reflexología podal puede utilizarse para reducir la fatiga en pacientes en hemodiálisis. En los estudios investigados no se proporcionó información sobre los posibles efectos secundarios y negativos de la reflexología podal.

Objective: this meta-analysis study analyzed the effect of foot reflexology on fatigue in hemodialysis patients by combining the results of independent studies on this subject. Method: meta-analysis study. A literature search was conducted in seven databases. The methodological quality of the included studies was assessed using tools proposed by the Joanna Briggs Institute. Comprehensive Meta-Analysis v3 was used for meta-analysis. Results: eight studies were included in the meta-analysis. The result of the meta-analysis standardized mean difference = 1.580 (95% Confidence Interval = 1.075 - 2.085 p = 0.000). The result of the subgroup analysis performed based on the number of foot reflexology sessions standardized mean difference = 1,478 (95% Confidence Interval = 1,210 - 1,747, p = 0.000). Conclusion: it was concluded that foot reflexology can be used to reduce fatigue in hemodialysis patients. No information was provided in the investigated studies about the possible side effects and negative effects of foot reflexology.

Objetivo: analisar o efeito da reflexologia podal sobre a fadiga em pacientes em hemodiálise, combinando os resultados de estudos independentes sobre este assunto. Método: estudo de metanálise. Foi realizada uma pesquisa bibliográfica em sete bases de dados. A qualidade metodológica dos estudos incluídos foi avaliada por meio de ferramentas propostas pelo Joanna Briggs Institute. Para a metanálise, foi utilizado o Comprehensive Meta-Analysis v3. Resultados: oito estudos foram incluídos na metanálise. O resultado da diferença média padronizada da metanálise = 1,580 (Intervalo de Confiança de 95% = 1,075 - 2,085 p = 0,000). O resultado da análise de subgrupo realizada com base na diferença média padronizada do número de sessões de reflexologia podal = 1,478 (Intervalo de Confiança de 95% = 1,210 - 1,747, p = 0,000). Conclusão: a reflexologia podal pode ser utilizada para reduzir a fadiga em pacientes em hemodiálise. Não foram fornecidas informações nos estudos investigados sobre os possíveis efeitos colaterais e negativos da reflexologia podal.

Percutaneous ethanol injection in thyroid nodular pathology and metastatic cervical adenopathies: A systematic review, meta-analysis and economic evaluation.

BACKGROUND: Percutaneous ethanol injection (PEI) has been shown to be a valuable treatment for thyroid nodular pathology and metastatic cervical adenopathies. OBJECTIVE: To evaluate the effectiveness, safety, and cost-effectiveness of PEI in thyroid nodular pathology and metastatic cervical adenopathies. METHODS: A systematic review (SR) using meta-analysis was conducted on the effectiveness and safety of PEI. A SR on cost-effectiveness was also performed. The SRs were conducted according to the methodology developed by the Cochrane Collaboration with reporting in accordance with the PRISMA statement. A cost-minimization analysis was carried out using a decision tree model. Assuming equal effectiveness between two minimally invasive techniques (PEI and radiofrequency ablation (RFA)), the model compared the costs of the alternatives with a horizon of six months and from the perspective of the Spanish National Health System. RESULTS: The search identified three RCTs (n=157) that evaluated PEI versus RFA in patients diagnosed with benign thyroid nodules: ninety-six patients with predominantly cystic nodules and sixty-one patients with solid nodules. No evidence was found on other techniques or thyroid nodular pathology. No statistically significant differences were observed between PEI and RFA in volume reduction (%), symptom score, cosmetic score, therapeutic success and major complications. No economic evaluations were identified. The cost-minimization analysis estimated the cost per patient of the PEI procedure at €326 compared to €4781 for RFA, which means an incremental difference of -€4455. CONCLUSIONS: There are no differences between PEI and RFA regarding their safety and effectiveness, but the economic evaluation determined that the former option is cheaper.

Treatment of dissociative symptoms with opioid antagonists: a systematic review.

BACKGROUND: The clinical guidelines for the treatment of dissociation focus primarily on psychotherapy. However, different psychoactive drugs are used in clinical practice. The use of opioid antagonists has been proposed as a therapeutic option based on the theory that dissociation might be a phenomenon mediated by dysregulation of the endogenous opioid system. OBJECTIVE: To review and meta-analyse the available evidence on the efficacy of the opioid antagonists naltrexone, naloxone, and nalmefene as treatments for dissociative symptoms and disorders. METHOD: The PRISMA guidelines were followed, and this review was registered in Prospero with reference number CRD42021280976. The search was performed in the PubMed, Scopus, Web of Science, EMBASE, PsycINFO, and PubPsych databases. RESULTS: 1,798 citations were obtained. After removing duplicates and applying inclusion and exclusion criteria, we included 5 comparative studies with 9 dissociation measures that had included a total of 154 participants, of whom 134 had been treated with an opioid antagonist. The results of the meta-analysis showed a treatment effect for dissociation when using opioid antagonists [pooled d = 1.46 (95% CI: 0.62-2.31)]. However, the studies we included were very heterogeneous [Q = 66.89 (p < .001)] and there may have been publication bias. CONCLUSIONS: Although more research is needed and the results must be interpreted with caution because of the limited amount of data and heterogeneity in the studies and their methodological qualities, opioid antagonists (particularly naltrexone) are promising candidates for the treatment of dissociative symptoms and showed a moderate - large effect size in reducing these symptoms.

The results of the meta-analysis showed a treatment effect for dissociation when using opioid antagonists [pooled d = 1.46 (95% CI: 0.62­2.31)].The results must be interpreted with caution because of the limited amount of data and heterogeneity in the studies and their methodological qualities.Opioid antagonists (particularly naltrexone) are promising candidates for the treatment of dissociative symptoms and showed a moderate ­ large effect size in reducing these symptoms.

Results beyond 5-years of surgery or percutaneous approach in severe coronary disease. Reconstructed time-to-event meta-analysis of randomized trials.

INTRODUCTION AND OBJECTIVES: There is controversy about the optimal revascularization strategy in severe coronary artery disease (CAD), including left main disease and/or multivessel disease. Several meta-analyses have analyzed the results at 5-year follow-up but there are no results after the fifth year. We conducted a systematic review and meta-analysis of randomized clinical trials, comparing results after the fifth year, between coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) using drug-eluting stents in patients with severe CAD. METHODS: We analyzed all clinical trials between January 2010 and January 2023. The primary endpoint was all-cause mortality. The databases of the original articles were reconstructed from Kaplan-Meier curves, simulating an individual-level meta-analysis. Comparisons were made at certain cutoff points (5 and 10 years). The 10-year restricted median survival time difference between CABG and PCI was calculated. The random effects model and the DerSimonian-Laird method were applied. RESULTS: The meta-analysis included 5180 patients. During the 10-year follow-up, PCI showed a higher overall incidence of all-cause mortality (HR, 1.19; 95%CI, 1.04-1.32; P=.008)]. PCI showed an increased risk of all-cause mortality within 5 years (HR, 1.2; 95%CI, 1.06-1.53; P=.008), while no differences in the 5-10-year period were revealed (HR, 1.03; 95%CI, 0.84-1.26; P=.76). Life expectancy of CABG patients was slightly higher than that of PCI patients (2.4 months more). CONCLUSIONS: In patients with severe CAD, including left main disease and/or multivessel disease, there was higher a incidence of all-cause mortality after PCI compared with CABG at 10 years of follow-up. Specifically, PCI has higher mortality during the first 5 years and comparable risk beyond 5 years.

Efecto de la cirugía bariátrica sobre calidad de vida en obesos: Una revisión sistemática global / Effect of bariatric surgery on quality of life in obese patients: A global systematic review

RESUMEN En situación de obesidad y cuando no se logra cumplir las metas del tratamiento, la cirugía bariátrica puede ser una alternativa prometedora, con efectos, a nivel físico y en el plano psicológico de la calidad de vida (CV). Este estudio tuvo como objetivo determinar el efecto de la cirugía bariátrica sobre la CV en hombres y mujeres obesas entre 20 y 60 años. Se realizó una revisión sistemática (RS) con metanálisis de RS aleatorizadas, que comparan la CV en los pacientes poscirugía bariátrica. Fueron consultadas las bases de datos electrónicas Ebsco, Scopus, Pubmed y Cochrane Library. Las variables de respuesta fueron las dimensiones función física, social, mental y emocional de la CV. Se sometieron a metanálisis con R 4.2.2. Se incluyeron tres RS, de las cuales se combinaron 25 ensayos clínicos con 3-6 y 12 meses de seguimiento poscirugía bariátrica. Se encontraron cambios estadísticamente significativos de los puntajes en función física (1,20; IC 95%: 0,80-1,61), social (0,95; IC 95%: 0,66-1,25), mental (0,35; IC 95%: -0,21- +0,90) y emocional (0,54; IC 95%: 0,03-1,06). Los ámbitos de la CV mejoran poscirugía bariátrica en pacientes obesos.

ABSTRACT In a situation of obesity and when treatment goals are not met, bariatric surgery can be a promising alternative; with effects at the physical level as well as at the psychological level of the quality of life. This study aims to determine the effect of bariatric surgery on the quality of life in obese men and women between 20 and 60 years of age. A systematic review (SR) was carried out with meta-analysis of randomized systematic reviews, which compare the quality of life in patients after bariatric surgery. Electronic databases were consulted: Ebsco, Scopus, Pubmed and Cochrane Library. The response variables were: physical, social, mental and emotional function. They were submitted to meta-analysis, with R 4.2.2. Three SR were included, of which 25 clinical trials were combined with 3-6 and 12-month follow-up after bariatric surgery, finding statistically significant changes in physical function scores (1.20; 95% CI: 0.80-1 .61), social (0.95; 95% CI: 0.66-1.25), mental (0.35; 95% CI: -0.21- +0.90) and emotional (0.54; 95% CI: 0.03-1.06). The surroundings of the quality of life improve post bariatric surgery in obese patients.

Neurofeedback for post-traumatic stress disorder: systematic review and meta-analysis of clinical and neurophysiological outcomes.

Background: Posttraumatic stress disorder (PTSD) is a debilitating condition affecting millions of people worldwide. Existing treatments often fail to address the complexity of its symptoms and functional impairments resulting from severe and prolonged trauma. Electroencephalographic Neurofeedback (NFB) has emerged as a promising treatment that aims to reduce the symptoms of PTSD by modulating brain activity.Objective: We conducted a systematic review and meta-analysis of ten clinical trials to answer the question: how effective is NFB in addressing PTSD and other associated symptoms across different trauma populations, and are these improvements related to neurophysiological changes?Method: The review followed the Preferred Reporting Items for Systematic Reviews and Meta analyses guidelines. We considered all published and unpublished randomised controlled trials (RCTs) and non-randomised studies of interventions (NRSIs) involving adults with PTSD as a primary diagnosis without exclusion by type of trauma, co-morbid diagnosis, locality, or sex. Ten controlled studies were included; seven RCTs and three NRSIs with a total number of participants n = 293 (128 male). Only RCTs were included in the meta-analysis (215 participants; 88 male).Results: All included studies showed an advantage of NFB over control conditions in reducing symptoms of PTSD, with indications of improvement in symptoms of anxiety and depression and related neurophysiological changes. Meta-analysis of the pooled data shows a significant reduction in PTSD symptoms post-treatment SMD of -1.76 (95% CI -2.69, -0.83), and the mean remission rate was higher in the NFB group (79.3%) compared to the control group (24.4%). However, the studies reviewed were mostly small, with heterogeneous populations and varied quality.Conclusions: The effect of NFB on the symptoms of PTSD was moderate and mechanistic evidence suggested that NFB leads to therapeutic changes in brain functioning. Future research should focus on more rigorous methodological designs, expanded sample size and longer follow-up.

Neurofeedback (NFB) was found to have moderate beneficial effects on PTSD symptoms, and positive effects on secondary outcomes such as depression and anxiety, according to a meta-analysis of seven randomised controlled trials (RCTs).The beneficial effects of NFB were observed across diverse populations, including those with different types of trauma (military and civilians) and from different ethnic backgrounds.Results suggest that modulation of alpha rhythm might be a viable NFB protocol in patients with PTSD, as changes in neurophysiological functioning, such as connectivity in the Default Mode Network (DMN) and Salience Network (SN), were observed post-NFB and were correlated with a decrease in PTSD severity.

Does chlorhexidine reduce the incidence of ventilator-associated pneumonia in ICU patients? A systematic review and meta-analysis / El cuidado bucal de rutina con clorhexidina reduce la incidencia de neumonía asociada al ventilador en pacientes de la UCI? Una revisión sistemática y metanálisis

Objective This study aimed to investigate chlorhexidine’s efficacy in preventing ventilator-associated pneumonia (VAP). Design A systematic review and meta-analysis were conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Settings The data were obtained from Pubmed, Cochrane Library, and EMBASE. Patients or participants Only mechanically ventilated patients for at least 48h were included. Interventions Randomized clinical trials applying any dosage form of chlorhexidine were eligible. Main variables of interest The relative risk (RR) of the VAP incidence and all-cause mortality was assessed using the random-effects model. The mean difference in days of mechanical ventilation duration and intensive care unit (ICU) length of stay were also appraised. Results Ten studies involving 1233 patients were included in the meta-analysis. The oral application of CHX reduced the incidence of VAP (RR, 0.73 [95% CI, 0.55, 0.97]) and did not show an increase in all-cause mortality (RR, 1.13 [95% CI, 0.96, 1.32]). Conclusions CHX proved effective to prevent VAP. However, a conclusion on mortality rates could not be drawn because the quality of the evidence was very low for this outcome (AU)

Objetivo Este estudio tuvo como objetivo investigar la eficacia de la clorhexidina en la prevención de la neumonía asociada al ventilador (NAV). Diseño se realizó una revisión sistemática y un metanálisis siguiendo los elementos de informe (PRISMA) Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Ámbito Los datos se obtuvieron de Pubmed, Cochrane Library y EMBASE. Pacientes o participantes solo se incluyeron pacientes con ventilación mecánica durante al menos 48 horas. Intervenciones Fueron elegibles los ensayos clínicos aleatorios que aplicaban cualquier forma de dosificación de clorhexidina. Variables de interés principales Se evaluó el riesgo relativo (RR) de incidencia de NAVM y mortalidad por todas las causas mediante el modelo de efectos aleatorios. También se evaluó la diferencia media en los días de duración de la ventilación mecánica y la duración de la estancia en la unidad de cuidados intensivos (UCI). Resultados Diez estudios con 1233 pacientes se incluyeron en el metanálisis. La aplicación oral de CHX redujo la incidencia de VAP (RR, 0,73 [IC 95%, 0,55, 0,97]) y no mostró un aumento en la mortalidad por todas las causas (RR, 1,13 [IC 95%, 0,96, 1,32]. Conclusiones CHX demostró ser eficaz para prevenir la VAP. Sin embargo, no se pudo establecer una conclusión sobre las tasas de mortalidad porque la calidad de la evidencia fue muy baja para este resultado (AU)

Transdiagnostic psychosocial interventions to promote mental health in forcibly displaced persons: a systematic review and meta-analysis.

Background: People forced to leave their homes, such as refugees and internally displaced persons, are exposed to various stressors during their forced displacement, putting them at risk for mental disorders.Objective: To summarize evidence on the efficacy of psychosocial interventions aiming to promote mental health and/or to prevent mental symptoms by fostering transdiagnostic skills in forcibly displaced persons of all ages.Method: Four databases and reference lists were searched for randomized controlled trials on interventions in this population on 11 March 2022. Thirty-six studies were eligible, 32 studies (comprising 5299 participants) were included in random-effects multilevel meta-analyses examining the effects of interventions on mental symptoms and positive mental health (e.g. wellbeing) as well as moderators to account for heterogeneity. OSF Preregistration-ID: 10.17605/OSF.IO/XPMU3Results: Our search resulted in 32 eligible studies, with 10 reporting on children/adolescents and 27 on adult populations. There was no evidence for favourable intervention effects in children/adolescents, with 44.4% of the effect sizes pointing to potentially negative effects yet remaining non-significant. For adult populations, our meta-analyses showed a close-to-significant favourable effect for mental symptoms, M(SMD) = 0.33, 95% CI [-0.03, 0.69], which was significant when analyses were limited to high-quality studies and larger for clinical compared to non-clinical populations. No effects emerged for positive mental health. Heterogeneity was considerable and could not be explained by various moderators (e.g. type of control, duration, setting, theoretical basis). Certainty of evidence was very low across all outcomes limiting the generalizability of our findings.Conclusion: The present review provides at most weak evidence for an effect favouring transdiagnostic psychosocial interventions over control conditions for adult populations but not for children and adolescents. Future research should combine the imperative of humanitarian aid in face of major crises with studying the diverse needs of forcibly displaced persons to improve and tailor future interventions.

This review is the first to examine the efficacy of transdiagnostic interventions for mental health promotion and prevention of mental disorders in forcibly displaced persons of all ages.Overall, we found no favourable effect of transdiagnostic interventions in both children/adolescents and adults. Excluding studies at high risk of bias, there was weak evidence for a small favourable effect in adults, but not in children and adolescents. Thus, so far, there is weak evidence for transdiagnostic interventions in forcibly displaced persons.Research efforts need to match care needs: While most people live and need care in low-income countries, the majority of research has been conducted in high-income countries.

Análisis de la heterogeneidad en revisiones sistemáticas de cardiología publicadas entre 2000-2005 y 2011-2016 / Analysis of heterogeneity in cardiology systematic reviews published be-tween 2000-2005 and 2011-2016 / Análise da heterogeneidade em revisões sistemáticas de cardiologia publicadas entre 2000-2005 e 2011-2016

Introducción: la cardiología es una de las especialidades médicas que cuenta con más revisiones sistemáticas y metanálisis. Estudiar la metodología de las revisiones y anali­zar su heterogeneidad estadística es fundamental para garantizar su validez científica. Objetivo: describir la comparación de medidas de asociación, modelos estadísticos y grado de heterogeneidad en metanálisis de revisiones sistemáticas de intervenciones farmacológicas en cardiología, publicadas entre 2000-2005 y 2011-2016. Metodología: estudio analítico basado en la descripción y comparación de métodos estadísticos de revisiones sistemáticas de intervenciones farmacológicas en cardiología, publicadas en la biblioteca Cochrane. Para las variables cualitativas se estimaron frecuen­cias absolutas y relativas, mientras que para las cuantitativas se determinaron medias y desviaciones estándar, o medianas y rangos intercuartílicos, según su distribución. Para establecer la diferencia de medias se realizó la prueba t de Student y para la diferencia de proporciones el Chi cuadrado. Resultados: se incluyeron 54 revisiones sistemáticas, con un total de 1053 metanálisis, 6 revisiones con 240 metanálisis entre 2000-2005 y 48 revisiones con 813 metanálisis entre 2011-2016. La mayoría de metanálisis utilizaron el tratamiento estándar como grupo de comparación (56.6%), midieron desenlaces cualitativos nominales (86.3%), determinaron riesgos relativos (63.3%) y aplicaron modelos de efectos fijos (57.8%). En 2011-2016 se encontró una media del Índice de Higgins 17.5 menor que en 2000-2005 (p<0.05). Conclusión: se evidenció una disminución de la heterogeneidad estadística y un aumento en la implementación de modelos de efectos aleatorios, lo que da cuenta de una mayor rigurosidad a la hora de demostrar resultados verdaderamente significativos.

Introduction: cardiology is one of the medical specialties with the most systematic reviews and meta-analyses. Studying the methodology of the reviews and analyzing their statistical heterogeneity is essential to guarantee their scientific validity. Objective: to describe the comparison of association measures, statistical models and degree of heterogeneity in meta-analyses of systematic reviews of pharmacological interventions in cardiology, published between 2000-2005 and 2011-2016. Methodology: analytical study based on the description and comparison of statistical methods of systematic reviews of pharmacological interventions in cardiology, published in the Cochrane library. For the qualitative variables, absolute and relative frequencies were estimated, while for the quantitative ones, means and standard deviations, or medians and interquartile ranges, were determined, depending on their distribution. The Student's t test was used to establish the difference in means and the Chi square for the difference in proportions. Results: 54 systematic reviews were included, with a total of 1.053 meta-analyses, 6 reviews with 240 meta-analyses between 2000-2005, and 48 reviews with 813 meta-analyses between 2011-2016. Most meta-analyses used standard treatment as the comparison group (56.6%), measured nominal qualitative outcomes (86.3%), determined relative risks (63.3%), and applied fixed-effect models (57.8%). In the 2011-2016 period, an average of the Higgins Index was found to be 17.5 lower than in the 2000-2005 (p<0.05). Conclusion: there was evidence of a decrease in statistical heterogeneity and an increase in the implementation of random effects models, which accounts for greater rigor when it comes to demonstrating truly significant results.

Introdução: a cardiologia é uma das especialidades médicas com mais revisões sistemáticas e metanálises. Estudar a metodologia das revisões e analisar sua heterogeneidade estatística é essencial para garantir sua validade científica. Objetivo: descrever a comparação de medidas de associação, modelos estatísticos e grau de heterogeneidade em metanálises de revisões sistemáticas de intervenções farmacológicas em cardiologia, publicadas entre 2000-2005 e 2011-2016. Metodologia: estudo analítico baseado na descrição e comparação de métodos estatísticos de revisões sistemáticas de intervenções farmacológicas em cardiologia, publicadas na biblioteca Cochrane. Para as variáveis qualitativas foram estimadas frequências absolutas e relativas, enquanto para as quantitativas foram determinadas médias e desvios padrão, ou medianas e intervalos interquartis, dependendo de sua distribuição. O teste t de Student foi utilizado para estabelecer a diferença de médias e o qui-quadrado para a diferença de proporções. Resultados: foram incluídas 54 revisões sistemáticas, com um total de 1053 meta-análises, 6 revisões com 240 meta-análises entre 2000-2005 e 48 revisões com 813 meta-análises entre 2011-2016. A maioria das metanálises usou tratamento padrão como grupo de comparação (56.6%), mediu resultados qualitativos nominais (86.3%), determinou riscos relativos (63.3%) e aplicou modelos de efeito fixo (57.8%). Em 2011-2016, a média do Índice de Higgins foi 17.5 menor do que em 2000-2005 (p<0.05). Conclusão: evidenciou-se uma diminuição da heterogeneidade estatística e um aumento da implementação de modelos de efeitos aleatórios, o que confere maior rigor na demonstração de resultados verdadeiramente significativos.

Effect of home-based cardiac rehabilitation for patients with heart failure: a systematic review and meta-analysis / Rehabilitación para pacientes con insuficiencia cardíaca: una revisión sistemática y metanálisis

SUMMARY: This study is to investigate the effect of home-based cardiac rehabilitation (HBCR) on quality of life, functional capacity, and readmission rates in patients with heart failure. Randomized controlled trials (RCTs) were screened from Cochrane Library, CINAHL, EMBASE, and MEDLINE. The intervention group received a standardized HBCR or a comprehensive rehabilitation strategy that included HBCR. The participants in the control group received CR at a medical center or usual care without CR intervention. The main outcome measurements included quality of life, exercise capacity, mortality and re-hospitalization. This meta-analysis included 20 RCTs, in which 16 studies compared HBCR with usual care, and 4 studies compared HBCR with center-based CR. In comparison with the usual care, HBCR improved the total quality of life score [MD=-5.85, 95 % CI (-9.76, - 1.94), P=0.003, I2=75 %]. Patients with HBCR and usual care were significantly different in VO2max [MD=1.05 mL/kg/min, 95 % CI (0.35, 1.75), P=0.003, I2=46 %]. However, VO2max of patients with HBCR was not significantly different from those with center-based CR [MD=0.08 mL/kg/min, 95 % CI (-1.29, 1.44), P=0.91, I2=0 %]. There was statistically significant difference in the 6-min Walk Distance between usual care and HBCR (for distance [MD=11.84, 95 % CI (7.41, 16.28), P<0.00001, I2=0 %]; and for feet [MD=98.93, 95 % CI (26.79, 171.08), P=0.007, I2=56 %]). However, there was no significant difference in 6-min Walk Distance between patients with HBCR and center-based CR [MD=12.45, 95 % CI (-9.81, 34.72), P=0.27, I2=0 %] , or in anxiety and depression between patients with usual care and HBCR (for anxiety, [MD=-0.25, 95 % CI (-0.56, 0.05), P=0.11, I2=0 %]; for depression, [MD=-0.18, 95 % CI (-0.51, 0.16), P=0.30, I2=0 %] . No significant difference was found in death number [RR=1.04, 95 % CI (0.55, 1.98), P=0.90, I2=0 %] or in the number of re-hospitalization [RR=0.88, 95 % CI (0.66, 1.18), P=0.40, I2=0 %] between usual care and HBCR. For patients with heart failure, compare with usual care and center-based CR, HBCR can improve the total quality of life. Compare with usual care, HBCR can improve VO2max and 6-min Walk Distance, but compare with center- based CR, there are no differences in mortality, re-hospitalization rate or incidence of anxiety and depression. Additionally, center- based CR and HBCR showed similar outcomes and medical costs.

El objetivo de este estudio fue investigar el efecto de la rehabilitación cardíaca domiciliaria (HBCR) sobre la calidad de vida, la capacidad funcional y las tasas de reingreso en pacientes con insuficiencia cardíaca. Se seleccionaron ensayos controlados aleatorios (ECA) de la Biblioteca Cochrane, CINAHL, EMBASE y MEDLINE. El grupo de intervención recibió un HBCR estandarizado o una estrategia de rehabilitación integral que incluía HBCR. Los participantes del grupo de control recibieron RC en un centro médico o atención habitual sin intervención de RC. Las principales medidas de resultado incluyeron la calidad de vida, la capacidad de ejercicio, la mortalidad y la rehospitalización. Este metanálisis incluyó 20 ECA, en los que 16 estudios compararon HBCR con la atención habitual y 4 estudios compararon que mejoró la puntuación total de calidad de vida [DM=-5,85, IC del 95 % (-9,76, -1,94), P=0,003, I2=75 %]. Los pacientes con HBCR y atención habitual fueron significativamente diferentes en el VO2máx [DM = 1,05 ml/kg/ min, IC del 95 % (0,35, 1,75), P = 0,003, I2 = 46 %]. Sin embargo, el VO2max de los pacientes con HBCR no fue significativamente diferente de aquellos con CR basada en el centro [DM = 0,08 ml/kg/min, IC del 95 % (-1,29, 1,44), P = 0,91, I2 = 0 %]. Hubo una diferencia estadísticamente significativa en la distancia de caminata de 6 minutos entre la atención habitual y HBCR (para la distancia [DM=11,84, IC del 95 % (7,41, 16,28), P<0,00001, I2=0 %]; y para los pies [DM= 98,93, IC 95 % (26,79, 171,08), P=0,007, I2=56 %]). Sin embargo, no hubo una diferencia significativa en la distancia de caminata de 6 minutos entre los pacientes con HBCR y CR basada en el cen- tro [DM = 12,45, IC del 95 % (-9,81, 34,72), P = 0,27, I2 = 0 %], o en la ansiedad y depresión entre pacientes con atención habitual y HBCR (para ansiedad, [DM=-0,25, IC del 95 % (-0,56, 0,05), P=0,11, I2=0 %]; para depresión, [DM=-0,18, 95 % IC (- 0,51, 0,16), P=0,30, I2=0 %] No se encontraron diferencias significativas en el número de muertes [RR=1,04, IC del 95 % (0,55, 1,98), P=0,90, I2=0 %] o en el número de reingresos [RR=0,88, IC 95 % (0,66, 1,18), P=0,40, I2=0 %] entre atención habitual y HBCR. Para los pacientes con insuficiencia cardíaca, en comparación con la atención habitual y la CR en un centro, la HBCR puede mejorar la calidad de vida total. En comparación con la atención habitual, la HBCR puede mejorar el VO2máx y la distancia recorrida en 6 minutos, pero en comparación con la CR basada en un centro, no hay diferencias en la mortalidad, la tasa de rehospitalización o la incidencia de ansiedad y depresión. Además, CR y HBCR basados en el centro mostraron resultados y costos médicos similares.

Conservative versus liberal oxygen therapy in relation to all-cause mortality among patients in the intensive care unit: a systematic review of randomized controlled trials with meta-analysis and trial sequential analysis.

OBJECTIVE: To evaluate the benefits and harmful effects of conservative versus liberal oxygen therapy in patients admitted to the Intensive Care Unit (ICU). DESIGN: A systematic review and meta-analysis was carried out. SETTING: ICU. PARTICIPANTS: Adult patients (aged 18 years or older) were randomized to either a lower oxygenation target strategy (conservative oxygen therapy) or a higher oxygenation target strategy (liberal oxygen therapy) in the ICU. INTERVENTIONS: Patients received different oxygenation target strategies. RESULTS: Ten studies involving 5429 adult patients admitted to the ICU were included in the meta-analysis. The pooled results showed no decreased all-cause mortality at 28 days (RR 0.90; 95%CI 0.75-1.09; p = 0.28), 90 days (RR 1.02; 95%CI 0.92-1.13; p = 0.71) or longest follow-up (RR 0.97; 95%CI 0.88-1.08; p = 0.63) among patients administered conservative oxygen therapy. Secondary outcomes were comparable between the two groups. The results of sensitivity analyses and subgroup analyses were consistent with the main analyses. CONCLUSION: No beneficial or harmful effects of conservative oxygen therapy were found compared to liberal oxygen therapy in relation to all-cause mortality among adult patients in the ICU. Conservative oxygen therapy did not reduce all-cause mortality at 28 days, 90 days or longest follow-up. Other important clinical outcomes were also comparable between the two groups.

Does chlorhexidine reduce the incidence of ventilator-associated pneumonia in ICU patients? A systematic review and meta-analysis.

OBJECTIVE: This study aimed to investigate chlorhexidine's efficacy in preventing ventilator-associated pneumonia (VAP). DESIGN: A systematic review and meta-analysis were conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. SETTINGS: The data were obtained from Pubmed, Cochrane Library, and EMBASE. PATIENTS OR PARTICIPANTS: Only mechanically ventilated patients for at least 48h were included. INTERVENTIONS: Randomized clinical trials applying any dosage form of chlorhexidine were eligible. MAIN VARIABLES OF INTEREST: The relative risk (RR) of the VAP incidence and all-cause mortality was assessed using the random-effects model. The mean difference in days of mechanical ventilation duration and intensive care unit (ICU) length of stay were also appraised. RESULTS: Ten studies involving 1233 patients were included in the meta-analysis. The oral application of CHX reduced the incidence of VAP (RR, 0.73 [95% CI, 0.55, 0.97]) and did not show an increase in all-cause mortality (RR, 1.13 [95% CI, 0.96, 1.32]). CONCLUSIONS: CHX proved effective to prevent VAP. However, a conclusion on mortality rates could not be drawn because the quality of the evidence was very low for this outcome.

Moral injury and mental health among health-care workers during the COVID-19 pandemic: meta-analysis.

Background: During the COVID-19 pandemic, health-care workers (HCWs) may have been confronted with situations that may culminate in moral injury (MI). MI is the psychological distress that may result from perpetrating or witnessing actions that violate one's moral codes. Literature suggests that MI can be associated with mental health problems.Objective: We aimed to meta-analytically review the literature to investigate whether MI is associated with symptoms of posttraumatic stress disorder (PTSD), anxiety, depression, burnout, and suicidal ideation among active HCWs during the COVID-19 pandemic.Method: We searched eight databases for studies conducted after the onset of the COVID-19 pandemic up to 18 July 2023, and performed random-effects meta-analyses to examine the relationship between MI and various mental health outcomes.Results: We retrieved 33 studies from 13 countries, representing 31,849 individuals, and pooled 79 effect sizes. We found a positive association between MI and all investigated mental health problems (rs = .30-.41, all ps < .0001). Between-studies heterogeneity was significant. A higher percentage of nurses in the samples was associated with a stronger relationship between MI and depressive and anxiety symptoms. Samples with a higher percentage of HCWs providing direct care to patients with COVID-19 exhibited a smaller effect between MI and depressive and anxiety symptoms. We observed a stronger effect between MI and PTSD symptoms in US samples compared to non-US samples.Conclusion: We found that higher MI is moderately associated with symptoms of PTSD, anxiety, depression, burnout, and suicidal ideation among HCWs during the COVID-19 pandemic. Our findings carry limitations due to the array of MI scales employed, several of which were not specifically designed for HCWs, but underscore the need to mitigate the effect of potentially morally injurious events on the mental health of HCWs.

We conducted the first meta-analysis of moral injury and mental health among healthcare workers.Moral injury is moderately associated with symptoms of PTSD, depression, anxiety, burnout, and suicidal ideation.There was a stronger association between MI and anxiety and depressive symptoms for samples with more nurses.

Metanálises em psicologia: uma introdução conceitual e prática / Meta-analyses in psychology: a conceptual and hands-on introduction / Metanálisis en psicología: una introducción conceptual y práctica

Metanálise consiste em um conjunto de técnicas estatísticas que visa integrar os resultados de dois ou mais estudos primários. Ela permite produzir estimativas pontuais e intervalares de algum parâmetro populacional, geralmente uma medida de tamanho de efeito. Este artigo tem como objetivo apresentar conceitos fundamentais sobre metanálise e suas aplicações para psicólogos e estudantes de psicologia. O artigo: (1) introduz a lógica da metanálise, seus potenciais e as críticas a ela endereçadas; (2) apresenta dois modelos de metanálise comumente usados por pesquisadores; e (3) aborda dois tópicos importantes para a interpretação correta dos resultados: heterogeneidade e análise de subgrupos. Um exemplo fictício ilustra os conceitos ao longo do artigo. Os Materiais Suplementares contêm equações dos modelos apresentados no texto, resultados comentados de uma síntese metanalítica, código na linguagem R para reproduzir resultados e figuras desse artigo e uma breve lista comentada de fontes adicionais sobre metanálise. (AU)

Meta-analysis consists of a set of statistical techniques that aims to combine the results of two or more primary studies. It enables the calculation of point and interval estimates of some population parameter, usually a measure of effect size. The aim of this article is to introduce fundamental concepts of meta-analysis and its applications for psychologists and psychology students. The article: (1) introduces the logic of meta-analysis, its uses and common criticisms levied against it; (2) presents two computational models of meta-analysis commonly used by researchers; and (3) addresses two issues associated with the correct interpretation of results from meta-analyses: heterogeneity and subgroup analysis. A worked example illustrates the concepts throughout the article. The Supplementary Materials contain a worked example of the models presented in the text, a script in R language that allows the reader to reproduce the results, and a commented list of additional sources. (AU)

El metanálisis consiste en un conjunto de técnicas estadísticas que tiene como objetivo integrar los resultados de dos o más estudios primarios. Permite producir estimaciones puntuales y de intervalo de algún parámetro de población, generalmente una medida del tamaño del efecto. Este artículo presenta conceptos fundamentales sobre el metanálisis y sus aplicaciones para psicólogos y estudiantes de psicología. El artículo: (1) introduce la lógica del metanálisis, sus potencialidades y las críticas que se le dirigen; (2) presenta dos modelos de metanálisis comúnmente utilizados por los investigadores; y (3) aborda dos temas importantes para la correcta interpretación de los resultados: heterogeneidad y análisis de subgrupos. Un ejemplo ficticio ilustra los conceptos a lo largo del artículo. Los Materiales Suplementarios contienen ecuaciones de los modelos presentados en el texto, resultados comentados de una síntesis metanalítica, código en el lenguaje R para reproducir los resultados y las figuras de este artículo, y una breve lista comentada de fuentes adicionales. (AU)