RESUMO O câncer de pulmão (CP) é uma das neoplasias mais comuns e letais no Brasil, e apenas 15% dos pacientes são diagnosticados nos estágios iniciais. O tabagismo persiste como o responsável por mais de 85% de todos os casos. O rastreamento do CP (RCP) por meio da TC de baixa dosagem de radiação (TCBD) reduz a mortalidade do CP em 20%, e, quando combinado com a cessação do tabagismo, essa redução chega a 38%. Na última década, diversos países adotaram o RCP como recomendação de saúde populacional. No Brasil, embora ainda incipiente, a discussão sobre o tema é cada vez mais ampla e necessária. Com o intuito de aumentar o conhecimento e estimular o debate sobre o RCP, a Sociedade Brasileira de Cirurgia Torácica, a Sociedade Brasileira de Pneumologia e Tisiologia e o Colégio Brasileiro de Radiologia e Diagnóstico por Imagem constituíram um painel de especialistas para elaborar as recomendações para o RCP. As recomendações aqui apresentadas foram baseadas em revisão narrativa da literatura, com ênfase em grandes estudos populacionais, em revisões sistemáticas e em recomendações de diretrizes internacionais, sendo construídas após ampla discussão pelo grupo de especialistas. Os temas revisados foram os seguintes: porque rastrear, considerações gerais sobre tabagismo, epidemiologia do CP, critérios de elegibilidade, achados incidentais, lesões granulomatosas, modelos probabilísticos, requisitos mínimos da TCBD, aquisições volumétricas, riscos do rastreamento, estrutura mínima e papel da equipe multidisciplinar, conduta segundo o Lung CT Screening Reporting and Data System (Lung-RADS), custos vs. benefícios e perspectivas do rastreamento. (CP Brasil 15 iniciais 85 casos (RCP TCBD (TCBD 20 20% 38 38% década populacional incipiente necessária Torácica literatura populacionais internacionais seguintes rastrear elegibilidade incidentais granulomatosas probabilísticos volumétricas multidisciplinar LungRADS, LungRADS RADS , (Lung-RADS) vs 1 8 2 3 (Lung-RADS

ABSTRACT Although lung cancer (LC) is one of the most common and lethal tumors, only 15% of patients are diagnosed at an early stage. Smoking is still responsible for more than 85% of cases. Lung cancer screening (LCS) with low-dose CT (LDCT) reduces LC-related mortality by 20%, and that reduction reaches 38% when LCS by LDCT is combined with smoking cessation. In the last decade, a number of countries have adopted population-based LCS as a public health recommendation. Albeit still incipient, discussion on this topic in Brazil is becoming increasingly broad and necessary. With the aim of increasing knowledge and stimulating debate on LCS, the Brazilian Society of Thoracic Surgery, the Brazilian Thoracic Association, and the Brazilian College of Radiology and Diagnostic Imaging convened a panel of experts to prepare recommendations for LCS in Brazil. The recommendations presented here were based on a narrative review of the literature, with an emphasis on large population-based studies, systematic reviews, and the recommendations of international guidelines, and were developed after extensive discussion by the panel of experts. The following topics were reviewed: reasons for screening; general considerations about smoking; epidemiology of LC; eligibility criteria; incidental findings; granulomatous lesions; probabilistic models; minimum requirements for LDCT; volumetric acquisition; risks of screening; minimum structure and role of the multidisciplinary team; practice according to the Lung CT Screening Reporting and Data System; costs versus benefits of screening; and future perspectives for LCS. LC (LC tumors 15 stage 85 cases (LCS lowdose low dose (LDCT LCrelated related 20 20% 38 cessation decade populationbased population recommendation incipient necessary Surgery Association literature studies reviews guidelines reviewed criteria findings lesions models acquisition team System 1 8 2 3

SUMMARY The Guidelines Project, which is an initiative of the Brazilian Medical Association, aims to combine information from the medical field to standardize how to conduct and assist in the reasoning and decision-making of doctors. The information provided by this project must be critically evaluated by the physician responsible for the conduct that will be adopted, depending on the conditions and the clinical condition of each patient. Project Association decisionmaking decision making doctors adopted patient

Abstract Introduction Autism Spectrum Disorder (ASD) is a heterogeneous neurodevelopmental disorder, with main manifestations related to communication, social interaction, and behavioral patterns. The slight dynamics of change in the child over time require that the onset of clinical manifestations presented by the child be more valued, with the aim of stabilizing the condition. Faced with a variety of methods for diagnosing ASD, the question arises as to which method should be used. This systematic review aims to recommend the best tools to perform screening and diagnosis. Methodology This systematic review followed the PRISMA guidelines. The databases MEDLINE, Embase, CENTRAL (Cochrane), and Lilacs were accessed, and gray and manual searches were performed. The search strategy was created with terms referring to autism and the diagnosis/broad filter. The studies were qualitatively evaluated and quantitatively. Statistical analysis was performed using Meta-diSc-2.0 software, the confidence interval was 95 %. Results The M-CHAT-R/F tool demonstrated a sensitivity of 78 % (95 % CI 0.57‒0.91) and specificity of 0.98 (95 % CI 0.88-1.00). The diagnostic tools demonstrated sensitivity and specificity respectively of: ADOS, sensitivity of 87 % (95 % CI 0.79‒0.92) and specificity 75 % (95 % CI 0.73‒0.78); ADI-R demonstrated test sensitivity of 77 % (95 % CI 0.56‒0.90) and specificity 68 % (95 % CI 0.52‒0.81), CARS test sensitivity was 89 % (95 % CI 0.78‒0.95) and specificity 79 % (95 % CI 0.65‒0.88). Conclusion It is mandatory to apply a screening test, the most recommended being the M-CHAT-R/F. For diagnosis CARS and ADOS are the most recommended tools. ASD (ASD disorder communication interaction patterns valued condition used guidelines MEDLINE Embase Cochrane, Cochrane , (Cochrane) accessed diagnosisbroad broad filter quantitatively MetadiSc2.0 MetadiSc20 MetadiSc Meta diSc 2.0 2 0 Meta-diSc-2. software 9 MCHATR/F MCHATRF M CHAT R/F R F 7 (9 0.57‒0.91 057091 57 91 098 98 0.9 0.881.00. 088100 0.88 1.00 . 88 1 00 0.88-1.00) 8 0.79‒0.92 079092 92 0.73‒0.78 073078 73 0.73‒0.78) ADIR ADI 0.56‒0.90 056090 56 90 6 0.52‒0.81, 052081 0.52‒0.81 52 81 0.52‒0.81) 0.78‒0.95 078095 0.65‒0.88. 065088 0.65‒0.88 65 0.65‒0.88) MCHATR/F. R/F. (Cochrane MetadiSc2 MetadiSc2. 20 2. Meta-diSc-2 MCHATR RF ( 0.57‒0.9 05709 5 09 0. 881 0.881.00 08810 088 0.8 100 1.0 0.88-1.00 0.79‒0.9 07909 0.73‒0.7 07307 0.56‒0.9 05609 05208 0.52‒0.8 0.78‒0.9 07809 06508 0.65‒0.8 Meta-diSc- 0.57‒0. 0570 0.881.0 0881 08 10 1. 0.88-1.0 0.79‒0. 0790 0.73‒0. 0730 0.56‒0. 0560 0520 0.52‒0. 0.78‒0. 0780 0650 0.65‒0. Meta-diSc 0.57‒0 057 0.881. 0.88-1. 0.79‒0 079 0.73‒0 073 0.56‒0 056 052 0.52‒0 0.78‒0 078 065 0.65‒0 0.57‒ 05 0.881 0.88-1 0.79‒ 07 0.73‒ 0.56‒ 0.52‒ 0.78‒ 06 0.65‒ 0.57 0.88- 0.79 0.73 0.56 0.52 0.78 0.65 0.5 0.7 0.6

RESUMO Contexto: O câncer colorretal é o terceiro câncer mais comum na população, e a prevenção é principalmente baseada em programas de screening, com a ressecção completa de lesões neoplásicas. Múltiplas técnicas de ressecção estão disponíveis, mas ainda há controvérsias sobre a melhor abordagem, especialmente em relação à taxa de ressecção completa e à taxa de sangramento tardio. Objetivo: Nosso objetivo foi avaliar a melhor técnica de polipectomia com alça para lesões colorretais de até 10 mm. Métodos: Foi realizada uma busca abrangente em bancos de dados eletrônicos (MEDLINE e EMBASE) para identificar ensaios clínicos randomizados que comparassem a ressecção com alça quente versus alça fria para pólipos de até 10 mm, seguindo as diretrizes PRISMA. Os desfechos incluíram taxa de ressecção completa, taxa de ressecção em bloco, tempo de polipectomia, tempo total do procedimento, sangramento imediato, sangramento tardio e perfuração. Resultados: Dezenove ensaios clínicos randomizados foram incluídos, totalizando 8.720 pacientes e 17.588 pólipos. A polipectomia com alça quente foi associada a uma maior taxa de ressecção completa (RD, 0,02; IC95% [+0,00, 0,04]; P=0,03; I 2=63%), embora também tenha sido associada a uma taxa mais alta de sangramento tardio (RD 0,00; IC95% [0,00, 0,01]; P=0,01; I 2=0%) e de sangramento tardio grave (RD 0,00; IC95% [0,00, 0,00]; P=0,04; I 2=0%). A polipectomia com alça fria foi associada a um menor tempo de polipectomia (MD -46,89 segundos; IC95% [-62,99, -30,79]; P<0,00001 I 2=90%) e a um menor tempo total de colonoscopia (DM -7,17 minutos; IC95% [-9,10, -5,25]; P<0,00001 I 2=41%). Não houve diferença significativa na taxa de ressecção em bloco (RD, 0,00; IC95% [-0,01, 0,01]; P=0,20; I 2=30%) ou na taxa de sangramento imediato (RD -0,00; IC95% [-0,01, 0,00]; P=0,34; I 2=11%). Não foram relatados casos de perfuração em nenhum dos grupos. Conclusão: A polipectomia com alça quente apresenta uma taxa ligeiramente mais alta de ressecção completa, mas, como está associada a um tempo de procedimento mais longo e a uma taxa mais alta de sangramento tardio em comparação com a polipectomia com alça fria, não pode ser recomendada como a abordagem padrão. A análise individualizada e a experiência pessoal devem ser consideradas ao escolher a melhor abordagem. Contexto população screening neoplásicas disponíveis Objetivo 1 mm Métodos MEDLINE EMBASE PRISMA Resultados incluídos 8720 8 720 8.72 17588 17 588 17.58 RD, RD 0,02 002 0 02 IC95 IC +0,00, 000 00 [+0,00 0,04 004 04 0,04] P=0,03 P003 P 03 2=63%, 263 2=63% , 2 63 2=63%) 0,00 0,00, [0,00 0,01 001 01 0,01] P=0,01 P001 2=0% 20 0,00] P=0,04 P004 2=0%. . MD 46,89 4689 46 89 -46,8 segundos 62,99, 6299 62 99 [-62,99 30,79 3079 30 79 -30,79] P000001 00001 P<0,0000 2=90% 290 90 DM 7,17 717 7 -7,1 minutos 9,10, 910 9 [-9,10 5,25 525 5 25 -5,25] 2=41%. 241 2=41% 41 2=41%) 0,01, [-0,01 P=0,20 P020 2=30% 230 -0,00 P=0,34 P034 34 2=11%. 211 2=11% 11 2=11%) grupos Conclusão padrão 872 72 8.7 1758 58 17.5 0,0 IC9 +0,00 [+0,0 P=0,0 P00 26 2=63 6 [0,0 2=0 46,8 468 4 -46, 62,99 629 [-62,9 30,7 307 3 -30,79 P00000 0000 P<0,000 2=90 29 7,1 71 -7, 9,10 91 [-9,1 5,2 52 -5,25 24 2=41 [-0,0 P=0,2 P02 2=30 23 -0,0 P=0,3 P03 21 2=11 87 8. 175 17. 0, +0,0 [+0, P=0, P0 2=6 [0, 2= 46, -46 62,9 [-62, 30, -30,7 P0000 P<0,00 2=9 7, -7 9,1 [-9, 5, -5,2 2=4 [-0, 2=3 -0, 2=1 +0, [+0 P=0 [0 -4 62, [-62 -30, P000 P<0,0 - 9, [-9 -5, [-0 -0 +0 [+ P= [ [-6 -30 P<0, [- -5 + -3 P<0 P<

ABSTRACT Background: Colorectal cancer is the third most common cancer, and prevention relies on screening programs with resection complete resection of neoplastic lesions. Objective: We aimed to evaluate the best snare polypectomy technique for colorectal lesions up to 10 mm, focusing on complete resection rate, and adverse events. Methods: A comprehensive search using electronic databases was conducted to identify randomized controlled trials comparing hot versus cold snare resection for polyps sized up to 10 mm, and following PRISMA guidelines, a meta-analysis was performed. Outcomes included complete resection rate, en bloc resection rate, polypectomy, procedure times, immediate, delayed bleeding, and perforation. Results: Nineteen RCTs involving 8720 patients and 17588 polyps were included. Hot snare polypectomy showed a higher complete resection rate (RD, 0.02; 95%CI [+0.00,0.04]; P=0.03; I 2=63%), but also a higher rate of delayed bleeding (RD 0.00; 95%CI [0.00, 0.01]; P=0.01; I 2=0%), and severe delayed bleeding (RD 0.00; 95%CI [0.00, 0.00]; P=0.04; I 2=0%). Cold Snare was associated with shorter polypectomy time (MD -46.89 seconds; 95%CI [-62.99, -30.79]; P<0.00001; I 2=90%) and shorter total colonoscopy time (MD -7.17 minutes; 95%CI [-9.10, -5.25]; P<0.00001; I 2=41%). No significant differences were observed in en bloc resection rate or immediate bleeding. Conclusion: Hot snare polypectomy presents a slightly higher complete resection rate, but, as it is associated with a longer procedure time and a higher rate of delayed bleeding compared to Cold Snare, it cannot be recommended as the gold standard approach. Individual analysis and personal experience should be considered when selecting the best approach. Background Objective 1 mm events Methods guidelines metaanalysis meta performed times perforation Results 872 1758 RD, RD 0.02 002 0 02 95CI CI 95 +0.00,0.04 000004 00 04 [+0.00,0.04] P=0.03 P003 P 03 2=63%, 263 2=63% , 2 63 2=63%) 0.00 000 0.00, [0.00 0.01 001 01 0.01] P=0.01 P001 2=0%, 20 2=0% 2=0%) 0.00] P=0.04 P004 2=0%. . MD 46.89 4689 46 89 -46.8 seconds 62.99, 6299 62 99 [-62.99 30.79 3079 30 79 -30.79] P<0.00001 P000001 00001 2=90% 290 90 7.17 717 7 17 -7.1 minutes 9.10, 910 9 [-9.10 5.25 525 5 25 -5.25] 2=41%. 241 2=41% 41 2=41%) Conclusion approach 87 175 0.0 +0.00,0.0 00000 [+0.00,0.04 P=0.0 P00 26 2=63 6 [0.0 2=0 46.8 468 4 8 -46. 62.99 629 [-62.9 30.7 307 3 -30.79 P<0.0000 P00000 0000 2=90 29 7.1 71 -7. 9.10 91 [-9.1 5.2 52 -5.25 24 2=41 0. +0.00,0. [+0.00,0.0 P=0. P0 2=6 [0. 2= 46. -46 62.9 [-62. 30. -30.7 P<0.000 P0000 2=9 7. -7 9.1 [-9. 5. -5.2 2=4 +0.00,0 [+0.00,0. P=0 [0 -4 62. [-62 -30. P<0.00 P000 - 9. [-9 -5. +0.00, [+0.00,0 P= [ [-6 -30 P<0.0 [- -5 +0.00 [+0.00, -3 P<0. +0.0 [+0.00 P<0 +0. [+0.0 P< +0 [+0. + [+0 [+

RESUMO RACIONAL: O bypass gástrico de uma anastomose (BGU tem ganhado destaque na busca por melhores resultados na cirurgia bariátrica. No entanto, a eficácia e segurança do BGUA, em relação ao bypass gástrico em Y de Roux (BGYR) e à gastrectomia vertical (GV), permanecem imprecisas. OBJETIVOS: Comparar a eficácia e segurança do BGUA em relação ao BGYR e GV no tratamento da obesidade. MÉTODOS: Realizamos uma busca sistemática nas bases de dados do PubMed, EMBASE, Cochrane, Lilacs e Google Scholar por ensaios clínicos randomizados que comparassem o BGUA ao BGYR ou GV na abordagem cirúrgica da obesidade. Agrupamos resultados para índice de massa corporal, porcentagem da perda de peso em excesso, remissão do diabetes mellitus tipo 2, complicações e taxas de doença do refluxo gastroesofágico. As análises estatísticas foram realizadas empregando o software R, versão 4.2.3. RESULTADOS: Dados de 854 pacientes foram extraídos de 11 ensaios clínicos randomizados, dos quais 422 (49,4%) foram submetidos ao BGUA, com seguimento médio variando de seis meses a cinco anos. Na análise combinada, o BGUA esteve associado a uma porcentagem da perda de peso em excesso significativamente maior no acompanhamento de um ano e a um índice de massa corporal significativamente menor no acompanhamento de cinco anos em pacientes submetidos ao BGUA. Por outro lado, as taxas de remissão da diabetes mellitus tipo 2, de complicações e da doença do refluxo gastroesofágico não foram significativamente diferentes entre os grupos. A qualidade geral das evidências foi considerada muito baixa. CONCLUSÕES: Nossos resultados corroboram a eficácia comparável do BGUA em relação ao BGYR e GV no tratamento da obesidade, mantendo diferenças não significativas nas taxas de remissão da diabetes mellitus tipo 2, complicações e doença do refluxo gastroesofágico. RACIONAL BGU bariátrica entanto (BGYR GV, , (GV) imprecisas OBJETIVOS obesidade MÉTODOS PubMed EMBASE Cochrane 2 R 423 4 3 4.2.3 RESULTADOS 85 1 42 49,4% 494 49 (49,4% combinada lado grupos baixa CONCLUSÕES (GV 4.2. 8 49,4 (49,4 4.2 49, (49, 4. (49 (4 (

ABSTRACT BACKGROUND: One anastomosis gastric bypass (OAGB) has gained prominence in the search for better results in bariatric surgery. However, its efficacy and safety compared to Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) remain ill-defined. AIMS: To compare the efficacy and safety of OAGB relative to RYGB and SG in the treatment of obesity. METHODS: We systematically searched PubMed, EMBASE, Cochrane Library, Lilacs, and Google Scholar databases for randomized controlled trials comparing OAGB with RYGB or SG in the surgical approach to obesity. We pooled outcomes for body mass index, percentage of excess weight loss, type-2 diabetes mellitus remission, complications, and gastroesophageal reflux disease. Statistical analyses were performed with R software (version 4.2.3). RESULTS: Data on 854 patients were extracted from 11 randomized controlled trials, of which 422 (49.4%) were submitted to OAGB with mean follow-up ranging from six months to five years. The meta-analysis revealed a significantly higher percentage of excess weight loss at 1-year follow-up and a significantly lower body mass index at 5-year follow-up in OAGB patients. Conversely, rates of type-2 diabetes mellitus remission, complications, and gastroesophageal reflux disease were not significantly different between groups. The overall quality of evidence was considered very low. CONCLUSIONS: Our results corroborate the comparable efficacy of OAGB in relation to RYGB and SG in the treatment of obesity, maintaining no significant differences in type-2 diabetes mellitus remission, complications, and gastroesophageal reflux disease rates. BACKGROUND (OAGB surgery However RouxenY Roux en Y (RYGB (SG illdefined. illdefined ill defined. defined ill-defined AIMS obesity METHODS PubMed EMBASE Library Lilacs type2 type 2 type- remission complications version 4.2.3. 423 4.2.3 . 4 3 4.2.3) RESULTS 85 1 42 49.4% 494 49 (49.4% followup follow up years metaanalysis meta analysis 1year year 5year 5 Conversely groups low CONCLUSIONS 4.2. 8 49.4 (49.4 4.2 49. (49. 4. (49 (4 (

Abstract Background: With the aim of reducing the risk of Cerebrovascular Accident (CVA) in patients with Non-Valvular Atrial Fibrillation (NVAF), Left Atrial Appendage Occlusion (LAAO) devices are emerging as an alternative to oral anticoagulants. Objective: To analyze the efficacy and safety of the LAAO procedure in patients with NVAF and contraindications and/or failure for oral anticoagulants. Method: The search for evidence was carried out in the electronic databases Medline and Embase till January 2024. Additional searches were conducted on Google Scholar. The clinical trials registry database was also consulted. Two blinded investigators performed the search, study selection, and data collection, and assessed quality and risk of bias using the Cochrane tool for randomized clinical trials. Meta-analyses of eligible trials were performed using RevMan 5.4.1 software. The random effects model was used for all analyses. Results: Five articles were selected, among which three were non-inferiority randomized clinical trials that analyzed the performance and safety of LAAO devices compared to the use of Vitamin K Antagonists (AVKs) or Novel Oral Anticoagulants (NOACs). No randomized clinical trials were found that analyzed populations with absolute contraindications to oral anticoagulants. Having as primary outcomes analyzed the occurrence of stroke (ischemic or hemorrhagic), cardiovascular or unexplained death and systemic embolism, the non-inferiority of the LAAO procedure compared to the use of oral anticoagulants was verified. Conclusions: For patients with an absolute contraindication to anticoagulation and/or failure to use oral anticoagulants, evidence for the use of LAAO devices is scarce. Background CVA (CVA NonValvular Non Valvular NVAF, , (NVAF) (LAAO Objective andor Method 2024 Scholar consulted selection collection Metaanalyses Meta analyses 541 5 4 1 5.4. software Results selected noninferiority non inferiority AVKs (AVKs NOACs. NOACs . (NOACs) ischemic hemorrhagic, hemorrhagic hemorrhagic) embolism verified Conclusions scarce (NVAF 202 54 5.4 (NOACs 20 5. 2

ABSTRACT Purpose: COVID-19 continues to be an urgent World issue. Receptors of angiotensin converting enzyme 2 (ACE2), gateway of SARS-CoV-2, are present in the lungs, bladder, prostate, and testicles. Therefore, these organs face high risk of damage caused by the virus and this mechanism may explain non-respiratory symptoms of the disease. Materials and Methods: This systematic review, guided by the PRIMSA statement, was proposed to elucidate possible urological complications of COVID-19. Searches were carried out in Medline (PubMed), Cochrane (CENTRAL), Embase, MedRxiv and LILACS. Bias analysis was made using the specific Newcastle-Ottawa Scale for each study design. Results: Search was carried out until April 2022, and 8,477 articles were identified. Forty-nine of them were included in this systematic review. There is evidence that lower urinary tract symptoms and acute scrotum may be signs of COVID-19 in men, although in a small proportion. Also, the disease may have a transitory impact on male fertility, evidenced by several alterations in sperm counts. However, it must be clarified whether this impact is transitory, or may last for longer periods. Several patients showed reduction of total value of testosterone. Two authors linked low levels of testosterone with worse outcomes of COVID-19, suggesting that the hormone may be used as an early biomarker of the severity of the disease. Moreover, it is extremely unlikely that SARS-CoV-2 is transmitted by semen. Conclusion: This systematic review identified possible repercussions of COVID-19 in the urinary as well as in the male reproductive system. Purpose COVID19 COVID 19 COVID-1 issue ACE2, ACE2 ACE , (ACE2) SARSCoV2, SARSCoV2 SARSCoV SARS CoV 2, lungs bladder prostate testicles Therefore nonrespiratory non respiratory Methods statement COVID19. 19. PubMed, PubMed (PubMed) CENTRAL, CENTRAL (CENTRAL) Embase LILACS NewcastleOttawa Newcastle Ottawa design Results 2022 8477 8 477 8,47 Fortynine Forty nine men proportion Also fertility counts However periods COVID19, 19, Moreover SARS-CoV- semen Conclusion system COVID1 1 COVID- (ACE2 (PubMed (CENTRAL 202 847 47 8,4 SARS-CoV (ACE 20 84 4 8,

RESUMO Objetivo: Avaliar a eficácia do uso de máscaras na prevenção da infecção por COVID-19. Métodos: Revisão sistemática e meta-análise de estudos de coorte e caso-controle, considerando o melhor nível de evidência disponível. Bancos de dados eletrônicos (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials e ClinicalTrials.gov) foram pesquisados para identificar estudos que avaliassem a eficácia do uso de máscaras em comparação com ausência de seu uso durante a pandemia de COVID-19. O risco de viés e a qualidade da evidência foram avaliados usando a ferramenta Cochrane risk of bias e Grading of Recommendations Assessment, Development, and Evaluation. Resultados: Dos 1.028 estudos identificados, 9 preencheram os critérios de inclusão (2 estudos de coorte e 7 estudos de caso-controle) e foram incluídos na análise. A meta-análise usando apenas estudos de coorte mostrou diferenças estatisticamente significativas: o uso de máscara de tecido diminuiu 21% [(risk difference = −0,21 (IC 95%: −0,34 a −0,07); I2 = 0%; p = 0,002] o risco de infecção por COVID-19, mas a qualidade da evidência foi baixa. Em relação aos estudos caso-controle, o uso de máscara cirúrgica reduziu a chance de infecção por COVID-19 [OR = 0,51 (IC 95%: 0,37-0,70); I2 = 47%; p = 0,0001], assim como o uso de máscara respiratória N95 [OR = 0,31 (IC 95%: 0,20-0,49); I2 = 0%; p = 0,00001], ambos com baixa qualidade de evidência. Conclusões: Nesta revisão sistemática com meta-análise, demonstramos a eficácia do uso de máscaras na prevenção da infecção por SARS-CoV-2 independentemente do tipo de máscara (máscara cirúrgica descartável, máscaras comuns, incluindo máscaras de tecido, ou respiradores N95), embora os estudos avaliados apresentassem evidências de baixa qualidade e vieses importantes. Objetivo COVID19. COVID19 COVID 19. 19 Métodos metaanálise meta análise casocontrole, casocontrole caso controle, controle caso-controle disponível MEDLINE, MEDLINE (MEDLINE EMBASE ClinicalTrials.gov ClinicalTrialsgov ClinicalTrials gov Assessment Development Evaluation Resultados 1028 1 028 1.02 identificados 2 ( significativas 21 021 0 −0,2 IC 95% 95 034 34 −0,3 −0,07 007 07 −0,07) I 0% 0,002 0002 002 COVID19, 19, COVID-1 OR 051 51 0,5 0,370,70 037070 0,37 0,70 37 70 0,37-0,70) 47% 47 0,0001, 00001 0,0001 , 0001 0,0001] N N9 031 31 0,3 0,200,49 020049 0,20 0,49 20 49 0,20-0,49) 0,00001, 000001 0,00001 0,00001] Conclusões metaanálise, análise, SARSCoV2 SARSCoV SARS CoV SARS-CoV- descartável comuns N95, N95) importantes COVID1 102 02 1.0 −0, 03 3 −0,0 00 0,00 000 COVID- 05 5 0, 370 0,370,7 03707 037 070 0,7 0,37-0,70 4 0000 0,000 200 0,200,4 02004 020 0,2 049 0,4 0,20-0,49 00000 0,0000 SARS-CoV 10 1. −0 0,0 0,370, 0370 0,37-0,7 0,200, 0200 04 0,20-0,4 − 0,370 0,37-0, 0,200 0,20-0, 0,37-0 0,20-0 0,37- 0,20-

ABSTRACT Objective: To evaluate the efficacy of wearing a mask to prevent COVID-19 infection. Methods: This was a systematic review and meta-analysis of cohort and case-control studies, considering the best level of evidence available. Electronic databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Clinical Trials.gov) were searched to identify studies that evaluated the effectiveness of wearing masks compared with that of not wearing them during the COVID-19 pandemic. Risk of bias and quality of evidence were assessed using the Cochrane risk of bias tool and the Grading of Recommendations Assessment, Development, and Evaluation. Results: Of the 1,028 studies identified, 9 met the inclusion criteria (2 cohort studies and 7 case-control studies) and were included in the analysis. The meta-analysis using cohort studies alone showed statistically significant differences, wearing a cloth mask decreased by 21% [RD = −0.21 (95% CI, −0.34 to −0.07); I2 = 0%; p = 0,002] the risk of COVID-19 infection, but the quality of evidence was low. Regarding case-control studies, wearing a surgical mask reduced the chance of COVID-19 infection [OR = 0.51 (95% CI, 0.37-0.70); I2 = 47%; p = 0.0001], as did wearing an N95 respirator mask [OR = 0.31 (95% CI, 0.20-0.49); I2 = 0%; p = 0.00001], both with low quality of evidence. Conclusions: In this systematic review with meta-analysis, we showed the effectiveness of wearing masks in the prevention of SARS-CoV-2 infection regardless of the type of mask (disposable surgical mask, common masks, including cloth masks, or N95 respirators), although the studies evaluated presented with low quality of evidence and important biases. Objective COVID19 COVID 19 COVID-1 Methods metaanalysis meta analysis casecontrol case control available MEDLINE, MEDLINE (MEDLINE EMBASE Trials Trials.gov Trialsgov gov pandemic Assessment Development Evaluation Results 1028 1 028 1,02 identified 2 ( differences 21 RD 021 0 −0.2 95% 95 (95 CI 034 34 −0.3 −0.07 007 07 −0.07) I 0% 0,002 0002 002 OR 051 51 0.5 0.370.70 037070 0.37 0.70 37 70 0.37-0.70) 47% 47 0.0001, 00001 0.0001 , 0001 0.0001] N N9 031 31 0.3 0.200.49 020049 0.20 0.49 20 49 0.20-0.49) 0.00001, 000001 0.00001 0.00001] Conclusions metaanalysis, analysis, SARSCoV2 SARSCoV SARS CoV SARS-CoV- disposable respirators, respirators respirators) biases COVID1 COVID- 102 02 1,0 −0. (9 03 3 −0.0 00 0,00 000 05 5 0. 370 0.370.7 03707 037 070 0.7 0.37-0.70 4 0000 0.000 200 0.200.4 02004 020 0.2 049 0.4 0.20-0.49 00000 0.0000 SARS-CoV 10 1, −0 0,0 0.370. 0370 0.37-0.7 0.00 0.200. 0200 04 0.20-0.4 − 0, 0.370 0.37-0. 0.0 0.200 0.20-0. 0.37-0 0.20-0 0.37- 0.20-