1http://dx.doi.org/10.20396/bjos.v21i00.8666351 Volume 21 2022 e226351 Original Article 1 Graduate Program in Dentistry, Meridional Faculty/IMED, Passo Fundo, Brazil. 2 Graduate Program in Dentistry, Pontifical Catholic University of Rio Grande do Sul – PUCRS, Porto Alegre, Brazil. Corresponding author: Rafael Sarkis Onofre Graduate Program in Dentistry, Meridional Faculty/IMED, Passo Fundo, Brazil. Email: rafael.onofre@imed.edu.br Editor: Dr Altair A. Del Bel Cury Received: July 14, 2021 Accepted: October 27, 2021 Reporting characteristics of systematic review abstracts published in the proceedings of the SBPqO meeting William Vinícius de Oliveira Santos1 , Lara Dotto2 , Rafael Sarkis-Onofre1,* Aim: This study aimed to assess the reporting characteristics of systematic review abstracts published in the proceedings of the Sociedade Brasileira de Pesquisa Odontológica (SBPqO) meeting. Methods: We selected abstracts published in the SBPqO meeting proceedings of 2019 and 2020, mentioning that a systematic review was conducted in the title, objective or methods sections. One researcher performed the screening and the data extraction after a pilot test training. The following data were extracted: affiliation of the primary author, dental specialization, the term “systematic review” mentioned in the title, reporting of the objective, reporting of eligibility criteria, reporting of information sources, reporting of the number of included studies and if a meta-analysis was performed. A descriptive analysis of the data was performed with data summarized as frequencies. Results: We included 235 abstracts. A total of 20 studies were from the Universidade de Uberlândia (8.5%), and the main specialization was Restorative and Esthetic Dentistry, with 47 studies (20%). Most of the studies mentioned the term “systematic review” in the title (n=219; 93.2%) and reported the objective (n=231; 98.3%). A great majority of studies did not report the eligibility criteria (n=97; 41.3%) or it was classified as unclear (n=96; 40.8%). The great majority of studies only reported the databases searched (n=103; 43.8%) or databases and date of search (n=74; 31.5%). Most of the studies reported the number of included studies (n=204; 86.8%). Conclusion: Based on this study, the reporting characteristics of systematic review abstracts published in the proceedings of the SBPqO meeting are satisfactory. However, there is room for improvement. Keywords: Dental research. Research report. Systematic reviews of topic. https://orcid.org/0000-0002-8643-5026 https://orcid.org/0000-0003-1535-4736 https://orcid.org/0000-0002-1514-7879 2 Santos et al. Introduction A systematic review is an important tool in health, and it is used for identifying, apprais- ing, and integrating the results of a specific field1,2. The number of systematic reviews in dentistry has been increasing in recent years, and the reporting quality is highly variable3-5. Much health research is presented at conferences and is publicly available as abstracts in the proceedings. The reporting quality of these abstracts is import- ant because systematic reviewers will in some situations decide to include a study (or not) based on the conference abstract because the full article is not available. The reporting quality of conference abstracts was assessed in different topics in health, including sports injury prevention, oncology, urology, psychiatry, surgery, and oral health6-13. However, there are no studies assessing abstracts of systematic reviews in dentistry published in the proceedings of conferences. The Sociedade Brasileira de Pesquisa Odontológica (SBPqO) meeting is the most important conference in oral health research in Brazil, and it is the Brazilian division of the International Association for Dental Research. Since 2019, the SBPqO meeting has presented a special section dedicated to systematic review presentation, and all studies are published in the proceedings of the SBPqO meeting14,15. Therefore, this study aimed to assess the reporting characteristics of systematic review abstracts published in the proceedings of the SBPqO meeting. Material and Methods Eligibility criteria and search We included abstracts mentioning that a systematic review was conducted in the title, objective, or methods sections, regardless of the dental specialization discussed. We excluded studies which cited performing scoping reviews, overviews or assessing reporting quality of studies, or other methodological aspects characterizing the study as a meta-research. We performed a search in the proceedings of 201914 and 202015 to identify abstracts based on the eligibility criteria cited above, examining only the Systematic Reviews section. Screening Two researchers initially performed a pilot screening test discussing the inclusion criteria using the 2018 proceedings of the SBPqO meeting. One of the researchers subsequently identified studies by reviewing the titles and abstracts through the pdf versions of the 2019 and 2020 proceedings available at www.sbpqo.org.br. In case of any doubts, the opinion of a second researcher was requested. Data extraction We created a standardized form using the Excel program (Microsoft Excel 2020). We initially performed a pilot data extraction through a discussion between two reviewers to consider all data for extraction. Data from each systematic review were 3 Santos et al. subsequently extracted by one reviewer. The following data were collected: affiliation of primary author, dental specialization (Public Health, Endodontics, Oral and Maxillo- facial Pathology/stomatology, Radiology, Oral and Maxillofacial Surgery, Restorative and Esthetic Dentistry, Pediatric Dentistry, Periodontics, Orthodontics/Orthopedics, Implantology, and Others), the term “systematic review” mentioned in the title (Yes or No), reporting of the objective (Yes or No), reporting of eligibility criteria (Only inclusion criteria, Only exclusion criteria, Inclusion and exclusion criteria, Unclear, Not reported), reporting of information sources (Only databases, Only date of search, Databases and date of search, Unclear, Not reported), reporting of the number of included stud- ies (Yes, No, Unclear) and if a meta-analysis was performed (Yes or No). Data analysis A descriptive analysis of the data was performed with the data summarized as fre- quencies using the Excel program (Microsoft Excel 2020). Results We identified 262 abstracts published in the proceedings of the SBPqO meeting and classified as “systematic review”. We included 235 abstracts after the screening based on the eligibility criteria (see Supplemental Material). Table 1 presents the data related to the affiliation of the primary author and the dental specialization of the abstract. As a result, 20 studies were from the Universidade de Uberlândia (8.5%), followed by the Universidade de Santa Catarina (n=16;6.8%), while the Universidade Federal do Pará, Universidade Federal do Rio de Janeiro, Faculdade de Odontologia de Piracicaba (UNICAMP), and the Universidade Estadual Paulista (Araçatuba) presented 15 studies each (6.4%). The main specialization was Restor- ative and Esthetic Dentistry, numbering 47 studies (20%), followed by Oral and Maxil- lofacial Pathology/stomatology (n=41; 17.4%). Table 1. Characteristics of included studies Filiation of main author N % Universidade Federal de Uberlândia 20 8.5% Universidade Federal de Santa Catarina 16 6.8% Faculdade de Odontologia de Piracicaba (Unicamp) 15 6.4% Universidade Federal do Pará 15 6.4% Universidade Federal do Rio de Janeiro 15 6.4% Universidade Estadual Paulista - Araçatuba 15 6.4% Universidade Federal de Minas Gerais 10 4.3% Faculdade de Odontologia de São Leopoldo Mandic 9 3.8% Universidade Federal do Rio Grande do Sul 8 3.4% Universidade Federal Fluminense 7 3.0% Universidade Estadual da Paraíba 7 3.0% Universidade do Estado do Rio de Janeiro 6 2.55% Universidade de Pernambuco 5 2.13% Continue 4 Santos et al. Continuation Universidade de São Paulo - São Paulo 5 2.13% Universidade Federal Fluminense- Pólo Nova Friburgo 4 1.7% Universidade Positivo 4 1.7% Universidade Federal da Paraíba 4 1.7% Universidade de São Paulo- Bauru 4 1.7% Pontifícia Universidade Católica de Minas Gerais 4 1.7% Universidade de São Paulo- Ribeirão Preto 4 1.7% Centro Universitário CHRISTUS 3 1.3% Universidade Federal do Ceará 3 1.3% Universidade de Cuiába 3 1.3% Universidade Federal de Juiz de Fora 3 1.3% Universidade Estadual de Ponta Grossa 3 1.3% Universidade de Brasília 3 1.3% Universidade Estadual do Pará 2 0.8% Universidade do Oeste Paulista 2 0.8% Instituto de Ciências e Tecnologia / ICT-UNESP-SJC 2 0.8% Centro de Estudos Superiores de Maceió 2 0.8% Universidade Federal de Pelotas 2 0.8% Universidade Santo Amaro 2 0.8% Faculdade Paulo Picanço 2 0.8% Universidade Federal do Amazonas 2 0.8% Universidade Ibirapuera 2 0.8% Universidade Luterana do Brasil 1 0.4% Universidade Cruzeiro do Sul 1 0.4% Universidade Federal de Goiás 1 0.4% Faculdade Federal da Paraíba 1 0.4% Universidade Federal do Paraná 1 0.4% Universidade Norte do Paraná 1 0.4% Faculdade de Odontologia de Nova Friburgo 1 0.4% Pontifícia Universidade Católica do Rio Grande do Sul 1 0.4% Faculdade Meridional 1 0.4% Universidade Federal de Pernambuco 1 0.4% Universidade Federal do Maranhão 1 0.4% Centro Universitário Santo Agostinho 1 0.4% Universidade Iguaçu 1 0.4% Universidade Estadual Paulista - Araraquara 1 0.4% Universidade Federal do Espírito Santo 1 0.4% Centro Universitário da Fundação Hermínio Ometto 1 0.4% Escola Bahiana de Medicina e Saúde Pública 1 0.4% Universidade Estadual de Maringá 1 0.4% Universidade Nove de Julho 1 0.4% Pontifícia Universidade Católica do Paraná 1 0.4% Universidade de Taubaté 1 0.4% Continue 5 Santos et al. Figure 1 presents the reporting characteristics of the included abstracts. Most of studies mentioned the term “systematic review” in the title (n=219; 93.2%) and reported the objective (n=231; 98.3%). A great majority of studies did not report the eligibility criteria (n=97; 41.3%) or it was classified as unclear (n=96; 40.8%). In addi- Continuation Universidade Guarulhos 1 0.4% Dental specialties     Restorative and Esthetic Dentistry 47 20.00% Oral and Maxillofacial Pathology/stomatology 41 17.4% Orthodontics/Orthopedics 28 11.9% Periodontics 26 11.1% Endodontics 25 10.6% Pediatric Dentistry 18 7.7% Public Health 16 6.8% Oral and Maxillofacial Surgery 15 6.4% Implantology 11 4.7% Radiology 6 2.5% Others 2 0.8% Figure 1. Reporting characteristics of included abstracts. Systematic review mentioned in the title Objective reported 219 16 250 200 150 100 50 0N um be r o f a bs tr ac ts Yes No Answers Elegibility criteria reported 33 96 120 100 80 60 40 0N um be r o f a bs tr ac ts Only inclusion criteria Inclusion and exclusion criteria Only exclusion criteria Unclear Not reported Answers Answers 231 40 250 200 150 100 50 0N um be r o f a bs tr ac ts Yes No Answers Unclear 97 63 20 Reporting of information sources 103 8 120 100 80 60 40 0N um be r o f a bs tr ac ts Only databases Databases and date of search Only date of search Unclear Not reported 49 74 120 Number of included studies N um be r o f a bs tr ac ts 204 2110 250 200 150 100 50 0 Yes No Answers Unclear Meta-analysis performed 131 104 140 120 80 40 20 0N um be r o f a bs tr ac ts Yes No Answers 100 60 6 Santos et al. tion, the great majority of studies only reported the databases searched (n=103; 43.8%) or databases and date of search (n=74; 31.5%). Most of the studies reported the number of included studies (n=204; 86.8%), and most of the studies performed a meta-analysis (n=131; 55.7%). Discussion This is the first study in dentistry to assess the reporting characteristics of system- atic review abstracts published in proceedings of conferences. Our results demon- strated that most of the aspects evaluated are well-reported, and we believe that results could be related to the fact that the conference abstracts included were peer-reviewed by experienced reviewers before the publication of conference pro- ceedings. Also, our results are significant because the abstract could become a piv- otal element to support clinical decision-making in some situations, as highlighted by Johnson et al. (2013)16. However, most studies did not report the eligibility criteria, or it was classified as unclear. This fact could be related to the limited number of words to write the abstract. Details about what evidence was eligible or ineligible are important to the readers to comprehend the review scope. One of the possibilities to report the eligibility criteria is to use the PICO framework highlighting the Population, Intervention, Comparator, and Outcome included in the review17. A significant number of systematic review abstracts (n=235) were presented in the SBPqO meeting since establishing a special section for this type of study. Three aspects could be involved in this result: 1) Bassani et al. (2019)3 demonstrated that Brazil is one of the countries that publish the most systematic reviews in dentistry; 2) Dotto et al. (2020)18 showed that systematic reviews are well accepted as a Mas- ter’s or PhD thesis by Brazilian graduate programs in dentistry; and 3) Brazil has an upper-middle-income economy and systematic reviews are cheaper than other methodologies such as randomized controlled trials resulting in a research method- ology appropriate for this setting18. When analyzing the primary authors’ affiliation, we can observe universities from dif- ferent regions of Brazil which presented systematic reviews in the SBPqO meeting. The top university contributors could be the institutions where systematic reviews are well accepted in graduate programs, reflecting in their students presenting system- atic reviews in that meeting. The main specializations reported were Restorative and Esthetic Dentistry (20%) and Oral and Maxillofacial Pathology/stomatology (17.4%). Bassani et al. (2019)3 found that most specialization reporting in systematic reviews in dentistry indexed within PubMed during 2017 was Oral and Maxillofacial Surgery, followed by Oral and Maxillofacial Pathology/stomatology. The PRISMA 2020 statement17 was recently published, providing an updated reporting guidance for systematic review abstracts. The guidance includes a 12-item checklist specifying details about the systematic review title, background, methods, results, discussion, funding and registration. However, the number of words in abstracts could be limited in some conferences, jeopardizing the completeness of information reported. For example, the SBPqO recommendations about the number of words in 7 Santos et al. abstracts allow 1,470 characters, 120 in the title and 1,350 in the body of the text19. Also, the recommendations of the International Association for Dental Research20 General Session for abstracts allow 300 words or less, which is better than SBPqO, but it is still limited. We believe that it would be better to expand the number of words accepted in abstracts, but there are costs involved in this process. Also, one crucial aspect is including the use of reporting guidelines in the instructions to authors to help in the abstract writing. The most important limitation of our study is that we did not assess the abstracts published before the establishment of a systematic review section, and it is impossi- ble to evaluate the impact of this establishment in terms of the number of systematic reviews abstracts and reporting quality, and we did not assess all items recommended by PRISMA for abstracts. We believe that future assessments should focus on spin strategies and the extent and level of spin involved in systematic reviews abstracts. Thus, in light of the existence of a specific guideline for systematic review abstracts (PRISMA 2020)17, the SBPqO, which is the most important conference in oral health research in Brazil, should endorse the use of this statement to improve the reporting of abstracts and encourage students and researchers to use it. In conclusion, based on this study, the reporting characteristics of systematic review abstracts published in the proceedings of the SBPqO meeting are satisfactory. How- ever, there is room for improvement. Acknowledgements This study was conducted in a Graduate Program supported by CAPES, Brazil (Finance Code 001). RSO is funded in part by Meridional Foundation (Passo Fundo, Brazil), and WVOS is funded by the National Council for Scientific and Technological Development (CNPq, Brazil). However, these supporters had no role in the design of the study, in the collection or analysis of data, in the decision to publish or in preparing the manuscript. Data availability Datasets related to this article will be available upon request to the corresponding author. References 1. Cook DJ, Mulrow CD, Haynes RB. Systematic reviews: synthesis of best evidence for clinical decisions. Ann. Intern. Med. 1997;126(5):376-80. doi: 10.7326/0003-4819-126-5-199703010-00006. 2. Murad MH, Montori VM. Synthesizing evidence: shifting the focus from individual studies to the body of evidence. 2013; 309(21):2217-8. doi: 10.1001/jama.2013.5616. 3. 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Supplemental material List of numbers of included abstracts (2019). 1-RS001 42-RS045 83-RS097 2-RS002 43-RS046 84-RS098 3-RS003 44-RS048 85-RS099 4-RS004 45-RS049 86-RS100 5-RS005 46-RS050 87-RS101 6-RS006 47-RS051 88-RS102 7-RS007 48-RS052 89-RS103 8-RS008 49-RS054 90-RS104 9-RS010 50-RS055 91-RS105 10-RS011 51-RS057 92-RS106 11-RS012 52-RS058 93-RS107 12-RS013 53-RS059 94-RS109 13-RS014 54-RS060 95-RS110 14-RS016 55-RS061 96-RS111 15-RS017 56-RS062 97-RS113 16-RS018 57-RS064 98-RS114 17-RS019 58-RS065 99-RS115 18-RS020 59-RS068 100-RS116 19-RS021 60-RS069 101-RS117 20-RS022 61-RS070 102-RS118 21-RS023 62-RS071 103-RS119 22-RS024 63-RS072 104-RS121 23-RS025 64-RS073 105-RS122 24-RS026 65-RS075 106-RS123 25-RS027 66-RS076 107-RS124 26-RS028 67-RS077 108-RS126 27-RS029 68-RS078 109-RS128 28-RS030 69-RS079 110-RS129 29-RS031 70-RS082 111-RS130 30-RS032 71-RS083 112-RS131 31-RS033 72-RS084 113-RS132 32-RS034 73-RS085 114-RS134 33-RS035 74-RS086 115-RS135 34-RS036 75-RS087 116-RS136 35-RS037 76-RS088 117-RS137 36-RS038 77-RS090 118-RS138 37-RS040 78-RS091 119-RS139 38-RS041 79-RS092 120-RS140 39-RS042 80-RS093 121-RS142 40-RS043 81-RS094 41-RS044 82-RS096 10 Santos et al. List of numbers of included abstracts (2020). 122-RS001 160-RS041 198-RS081 123-RS002 161-RS043 199-RS082 124-RS003 162-RS044 200-RS083 125-RS004 163-RS045 201-RS084 126-RS005 164-RS046 202-RS085 127-RS006 165-RS048 203-RS086 128-RS007 166-RS049 204-RS087 129-RS008 167-RS050 205-RS088 130-RS009 168-RS051 206-RS089 131-RS010 169-RS052 207-RS090 132-RS012 170-RS053 208-RS091 133-RS013 171-RS054 209-RS092 134-RS014 172-RS055 210-RS093 135-RS015 173-RS056 211-RS094 136-RS016 174-RS057 212-RS095 137-RS017 175-RS058 213-RS096 138-RS018 176-RS059 214-RS097 139-RS019 177-RS060 215-RS098 140-RS020 178-RS061 216-RS099 141-RS021 179-RS062 217-RS100 142-RS023 180-RS063 218-RS101 143-RS024 181-RS064 219-RS102 144-RS025 182-RS065 220-RS103 145-RS026 183-RS066 221-RS104 146-RS027 184-RS067 222-RS105 147-RS028 185-RS068 223-RS107 148-RS029 186-RS069 224-RS108 149-RS030 187-RS070 225-RS109 150-RS031 188-RS071 226-RS111 151-RS032 189-RS072 227-RS112 152-RS033 190-RS073 228-RS113 153-RS034 191-RS074 229-RS114 154-RS035 192-RS075 230-RS115 155-RS036 193-RS076 231-RS116 156-RS037 194-RS077 232-RS117 157-RS038 195-RS078 233-RS118 158-RS039 196-RS079 234-RS119 159-RS040 197-RS080 235-RS120 11 Santos et al. Characteristics of each abstract included. Author/Year Systematic review mentioned in the title Objective reported Eligibility criteria reported Reporting of information sources Number of included studies Meta-analysis conducted Nunes et al., 2019 Yes Yes Not reported Only databases Yes Yes Reis et al., 2019 Yes Yes Only inclusion Only databases Yes No Frazão et al., 2019 Yes Yes Only inclusion Only databases Yes Yes Granja et al., 2019 Yes Yes Unclear Unclear Yes Yes Lacerda-Santos et al., 2019 Yes Yes Unclear Unclear Yes Yes Paulo et al., 2019 Yes Yes Not reported Only databases Yes No Pereira et al., 2019 Yes Yes Not reported Only databases Yes Yes Cetira-Filho Yes Yes Unclear Only databases Unclear Yes Novais et al., 2019 Yes Yes Unclear Unclear Yes Yes Amaral et al., 2019 Yes Yes Not reported Only databases Yes No Thuller et al., 2019 Yes Yes Only exclusion Only databases Yes Yes Falcão et al., 2019 Yes Yes Unclear Both Yes Yes Barbosa et al., 2019 Yes Yes Only inclusion Only databases Yes No Stringhini-Junior et al., 2019 Yes Yes Unclear Both Yes Yes Moraes et al., 2019 Yes Yes Only inclusion Both Yes Yes Alves et al., 2019 Yes Yes Only inclusion Both Yes Yes Basso et al., 2019 Yes Yes Unclear Only databases Yes Yes Wembier et al., 2019 Yes Yes Unclear Only databases Yes Yes Silva et al., 2019 Yes Yes Unclear Both Yes Yes Bronzato et al., 2019 Yes Yes Unclear Only databases Yes Yes Albuquerque et al., 2019 Yes Yes Not reported Both Yes No Castro et al., 2019 Yes Yes Unclear Only databases Yes Yes Pinto et al., 2019 Yes Yes Unclear Both Yes Yes Scarsi et al., 2019 Yes Yes Only inclusion Only databases Yes Yes Campos et al., 2019 Yes Yes Unclear Only databases Yes Yes Spinola et al., 2019 Yes Yes Not reported Only databases Yes No Oliveira et al., 2019 Yes Yes Not reported Only databases Yes Yes Terto et al., 2019 Yes Yes Only exclusion Both Yes Yes Castilho et al., 2019 Yes Yes Unclear Only databases Yes Yes Lima et al., 2019 Yes Yes Unclear Unclear No Yes Andrade et al., 2019 Yes Yes Unclear Only databases Yes Yes Baroni et al., 2019 Yes Yes Unclear Only databases Yes No Rende et al., 2019 No Yes Unclear Unclear Yes Yes Guimaraes et al., 2019 No Yes Not reported Only databases Yes Yes Fontes et al., 2019 Yes Yes Unclear Only databases Yes No Dantas et al., 2019 Yes Yes Only inclusion Both Yes Yes Continue 12 Santos et al. Continuation Milani et al., 2019 Yes Yes Unclear Only databases Unclear Yes Bedran et al., 2019 Yes Yes Not reported Only databases Yes Yes Cruz et al., 2019 Yes Yes Not reported Unclear Yes Yes Ribeiro-Lages et al., 2019 Yes Yes Not reported Only databases Yes Yes Mocchelini et al., 2019 Yes Yes Not reported Only databases Yes Yes Masson et al., 2019 Yes Yes Unclear Both Yes Yes Duarte et al., 2019 Yes Yes Not reported Only databases Yes Yes Seabra et al., 2019 Yes Yes Not reported Both Yes Yes Nadelman et al., 2019 Yes Yes Only inclusion Only databases Yes No Messignan et al., 2019 Yes Yes Not reported Only databases Yes Yes Dantas et al., 2019 Yes Yes Not reported Unclear No No Gonçalves et al., 2019 No Yes Not reported Only databases Yes Yes Oliveira et al., 2019 Yes Yes Both Both Yes No Bellini-Pereira et al., 2019 Yes Yes Only inclusion Both Yes Yes Prado et al., 2019 Yes Yes Only inclusion Only databases Yes Yes Pinheiro et al., 2019 Yes Yes Unclear Only databases Yes No Cardoso et al., 2019 Yes Yes Not reported Both Yes Yes Farias Junior et al.,2019 Yes Yes Unclear Both Yes No Silva et al., 2019 Yes Yes Only inclusion Both Yes No Silveira et al;. 2019 Yes Yes Unclear Unclear Yes No Nascimento et al., 2019 Yes Yes Unclear Both Yes No Neves et al., 2019 Yes Yes Unclear Not reported Unclear Yes Nunes et al., 2019 Yes Yes Unclear Only databases Unclear No Lins et al., 2019 No Yes Not reported Only databases Yes Yes Farias et al., 2019 Yes Yes Unclear Only databases Yes No Dietrich et al., 2019 Yes Yes Unclear Both Yes No Polmann et al., 2019 Yes Yes Not reported Only databases Yes No Maran et al., 2019 Yes Yes Not reported Only databases Yes Yes Lima et al., 2019 No Yes Unclear Both Yes No Martini et al., 2019 Yes Yes Not reported Only databases Yes No Antonio et al., 2019 Yes Yes Only inclusion Only databases Yes No Né et al., 2019 Yes Yes Unclear Unclear Yes No Fidalgo et al., 2019 Yes Yes Unclear Only databases Yes No Nascimento et al., 2019 No Yes Not reported Only databases Yes Yes Bacchin et al., 2019 Yes Yes Not reported Only databases Yes No Roithmann et al., 2019 Yes Yes Unclear Both Yes Yes Maroli et al., 2019 Yes Yes Both Only databases Yes No Carneiro-Campos et al., 2019 Yes Yes Only inclusion Both Unclear Yes Brunetto et al., 2019 Yes Yes Unclear Both Yes Yes Continue 13 Santos et al. Continuation Minatel et al., 2019 Yes Yes Not reported Only databases Yes No Lemos et al., 2019 Yes Yes Not reported Unclear Yes Yes Silva et al., 2019 Yes Yes Unclear Both Yes Yes Barcelos et al.,2019 Yes Yes Only exclusion Both Yes No Gomez et al., 2019 Yes Yes Not reported Both Yes No Magalhães et al., 2019 Yes Yes Not reported Only databases Yes No Sarmento et al., 2019 Yes Yes Unclear Both Yes No Barbosa et al., 2019 Yes Yes Not reported Unclear Yes Yes Lhano et al., 2019 Yes Yes Unclear Only databases Unclear Yes Oliveira et al., 2019 Yes Yes Not reported Both Yes Yes Nascimento et al., 2019 No Yes Not reported Only databases Yes Yes Oliveira et al., 2019 Yes Yes Unclear Only databases Yes Yes Silva et al., 2019 Yes Yes Both Only databases Yes Yes Dutra et al., 2019 Yes Yes Not reported Only databases Unclear Yes Macedo-Filho et al., 2019 Yes Yes Unclear Both Yes Yes Oliveira et al., 2019 Yes Yes Not reported Unclear Yes Yes Kammer et al.,2019 Yes Yes Not reported Unclear Yes Yes Berretta et al., 2019 Yes Yes Only inclusion Unclear Yes No Diniz et al., 2019 Yes Yes Unclear Unclear Yes No Reis et al., 2019 Yes Yes Unclear Unclear Yes No Silveira et al;. 2019 Yes Yes Only inclusion Unclear Yes Yes Martins et al., 2019 Yes Yes Not reported Unclear Yes Yes Jerônimo et al., 2019 Yes Yes Unclear Unclear Yes Yes Rosa et al., 2019 Yes Yes Unclear Both Yes Yes Lago et al., 2019 Yes Yes Unclear Both Yes Yes Haas et al., 2019 No Unclear Unclear Only databases Yes Yes Melo et al., 2019 Yes Yes Unclear Unclear Yes No Lavôr et al., 2019 Yes Yes Unclear Unclear Yes No Oliveira et al., 2019 Yes Yes Unclear Both Yes No Paulo et al., 2019 Yes Yes Unclear Unclear Yes Yes Lisboa et al., 2019 Yes Yes Not reported Only databases Yes No Martins et al., 2019 Yes Yes Only inclusion Only databases Yes No Campos et al., 2019 Yes Yes Not reported Only databases No No Rolim et al., 2019 Yes Yes Unclear Both Yes Yes Silva et al., 2019 Yes Yes Unclear Only databases Yes Yes Campos et al., 2019 Yes Yes Not reported Unclear Unclear No Souza et al., 2019 Yes Yes Unclear Only databases Yes Yes Miranda et al., 2019 Yes Yes Not reported Only databases Yes Yes Raymundo et al., 2019 Yes Yes Not reported Only databases No Yes Caldas et al., 2019 Yes Yes Not reported Both Yes No Continue 14 Santos et al. Continuation Miranda et al., 2019 Yes Yes Unclear Only databases Yes No Alvarenga et al., 2019 Yes Yes Not reported Unclear Yes Yes Santos et al., 2019 No Yes Not reported Only databases Yes No Rendohl et al., 2019 Yes Yes Only inclusion Both No Yes Limírio et al., 2019 Yes Yes Not reported Both Yes Yes Borges et al., 2019 Yes Yes Not reported Not reported Yes Yes Reis et al., 2020 Yes Yes Unclear Only databases Yes No Gonçalves et al., 2020 Yes Yes Unclear Both Yes Yes Vidigal et al., 2020 Yes Yes Not reported Unclear Yes Yes Leal et al., 2020 Yes Yes Not reported Both Yes No Silva et al., 2020 No Yes Unclear Both Yes No Rosatto et al., 2020 Yes Yes Not reported Unclear Yes No Sarmento et al., 2020 Yes Yes Not reported Unclear Yes No Matos et al., 2020 Yes Yes Not reported Unclear Yes No Gabriel et al., 2020 Yes Yes Not reported Unclear Yes Yes Dias-Junior et al., 2020 Yes Yes Unclear Only databases Yes Yes Nóbrega et al., 2020 Yes Yes Unclear Only databases Unclear Yes Sponchiado-Júnior et al., 2020 Yes Yes Unclear Only databases Yes No Martins et al., 2020 Yes Yes Unclear Only databases Yes No Pirovani et al., 2020 Yes Yes Unclear Both Yes No Feitosa et al., 2020 Yes Yes Only inclusion Only databases Yes No Salomão et al., 2020 Yes Yes Only inclusion Only databases Yes Yes Kwiatkowski et al., 2020 Yes Yes Unclear Both Yes No Lopes et al., 2020 Yes Yes Unclear Only databases Yes No Soares et al., 2020 Yes Yes Not reported Only databases Yes No Né et al., 2020 Yes Yes Unclear Only databases Yes Yes Carvalho et al., 2020 Yes Yes Unclear Only databases Yes No Araujo et al., 2020 Yes Yes Not reported Only databases Yes No Silver et al., 2020 Yes Yes Only inclusion Only databases Yes Yes Schoeffel et al., 2020 Yes Yes Only inclusion Unclear Yes Yes Muknickas et al., 2020 Yes Yes Unclear Only databases Unclear No Rezende et al., 2020 Yes Yes Unclear Both Yes No Oliveira et al., 2020 Yes Yes Only inclusion Both Yes Yes Cruz et al., 2020 Yes Yes Not reported Unclear Yes Yes Oliveira et al., 2020 Yes Yes Both Both Yes No Martins et al., 2020 Yes Yes Not reported Only databases Yes Yes Mocchelini et al., 2020 Yes Yes Not reported Only databases Yes Yes Miyahira et al., 2020 Yes Yes Unclear Only databases Yes Yes Machado et al., 2020 Yes Yes Only inclusion Both Yes No Miranda et al., 2020 Yes Yes Only inclusion Both Yes No Continue 15 Santos et al. Continuation Soares et al., 2020 Yes Yes Unclear Both Yes No Pintor et al., 2020 Yes Yes Only inclusion Both Yes No Camatta et al., 2020 Yes Yes Unclear Only databases No Yes Sanglard et al., 2020 Yes Yes Not reported Both Yes No Haibara et al., 2020 Yes Yes Unclear Both Yes No Fontes et al., 2020 Yes Yes Unclear Only databases Yes No Latieri et al., 2020 Yes Yes Unclear Both Yes No Bonzanini et al., 2020 Yes Yes Not reported Both Yes Yes Soares et al., 2020 Yes Yes Not reported Only databases Yes Yes Neves et al., 2020 Yes Yes Not reported Only databases Yes No Inocêncio et al., 2020 No Yes Unclear Unclear Unclear Yes Figueiredo et al., 2020 Yes Unclear Unclear Both Unclear No Rodrigues et al., 202 Yes Yes Unclear Both Unclear No Jácome-Santos et al., 2020 Yes Yes Not reported Both Yes No Sant ´Anna et al., 2020 Yes Yes Not reported Only databases Yes Yes Sant’anna et al., 2020 Yes Yes Unclear Unclear Yes Yes Mattos et al., 2020 Yes Yes Unclear Both Yes Yes Silveira-Júnior et al., 2020 Yes Yes Not reported Only databases Yes No Caetano et al., 2020 Yes Yes Unclear Only databases Yes No Figueiredo et al., 2020 Yes Yes Only inclusion Only databases No Yes Naal et al., 2020 Yes Yes Unclear Both Yes No Tardelli et al., 2020 Yes Yes Only inclusion Both Unclear No Lopes et al., 2020 Yes Yes Only inclusion Both Unclear Yes Kunz et al., 2020 No Yes Unclear Only databases Yes Yes Uehara et al., 2020 Yes Yes Both Only databases Yes No Limírio et al., 2020 Yes Yes Not reported Both Yes Yes Sanches et al., 2020 Yes Yes Not reported Both Yes Yes Veloso et al., 2020 Yes Yes Only inclusion Only databases Yes Yes Oliveira et al., 2020 Yes Yes Only inclusion Unclear Yes Yes Ortiz et al., 2020 Yes Yes Only inclusion Unclear Yes No Scherer et al., 2020 Yes Yes Not reported Both Yes Yes Andrade et al., 2020 Yes Yes Unclear Only databases Yes No Martini et al., 2020 Yes Yes Not reported Only databases Unclear Yes Valesan et al., 2020 Yes Yes Unclear Unclear Yes Yes Oliveira et al., 2020 Yes Yes Not reported Unclear Yes Yes Santos et al., 2020 Yes Yes Not reported Only databases Yes Yes Corso et al., 2020 Yes Yes Not reported Only databases Yes Yes Gama et al., 2020 Yes Yes Unclear Unclear Yes No Pinto et al., 2020 Yes Yes Unclear Both Yes No Parize et al., 2020 Yes Yes Not reported Unclear Yes No Continue 16 Santos et al. Continuation Sabatini et al., 2020 Yes Yes Unclear Unclear Yes No Camarini et al., 2020 Yes Yes Not reported Not reported No No Sakuma et al., 2020 Yes Yes Not reported Unclear Yes Yes Silva et al., 2020 Yes Yes Not reported Only databases No Yes Santaella et al., 2020 Yes Yes Not reported Only databases Yes No Guerra et al., 2020 Yes Yes Not reported Not reported Yes Yes Munhoz et al., 2020 No Yes Not reported Only date Yes No Ibarra et al., 2020 Yes Yes Not reported Not reported Yes No Ribeiro et al., 2020 Yes Yes Not reported Both Yes No Galdino et al., 2020 Yes Yes Not reported Only databases Yes Yes Magrin et al., 2020 Yes Yes Unclear Unclear Yes No Souza et al., 2020 Yes Yes Not reported Both Yes Yes Borges et al., 2020 Yes Yes Only inclusion Both Yes Yes Magalhães et al., 2020 Yes Yes Both Only databases Yes No Martinho et al., 2020 No Yes Not reported Unclear Unclear Yes Souza et al., 2020 Yes Yes Unclear Both Yes Yes Resende et al., 2020 Yes Yes Unclear Only databases Yes Yes Langa et al., 2020 Yes Yes Unclear Unclear Yes Yes Basso et al., 2020 No Yes Unclear Only databases Yes No Oliveira et al., 2020 Yes Unclear Not reported Unclear Yes Yes Campos et al., 2020 Yes Yes Not reported Both Unclear Yes Albuini et al., 2020 Yes Yes Unclear Not reported Yes No Koch et al., 2020 Yes Yes Unclear Only databases Yes No Soares et al., 2020 Yes Yes Unclear Unclear Unclear Yes Jakymiu et al., 2020 Yes Unclear Unclear Both Yes No Peinado et al., 2020 Yes Yes Not reported Only databases Yes No Domingues et al., 2020 Yes Yes Unclear Only databases Yes No Barbosa et al., 2020 Yes Yes Unclear Both Yes No Vieira et al., 2020 Yes Yes Not reported Unclear Yes Yes Santos et al., 2020 Yes Yes Not reported Only databases Yes No Macedo et al., 2020 Yes Yes Not reported Unclear Yes Yes Dini et al., 2020 Yes Yes Not reported Not reported Unclear Yes Macena et al., 2020 Yes Yes Not reported Only databases Yes Yes Spessato et al., 2020 Yes Yes Not reported Both Yes Yes Baccaro et al., 2020 Yes Yes Only inclusion Both Unclear No Silva et al., 2020 Yes Yes Not reported Both Yes Yes Linhares et al., 2020 Yes Yes Only inclusion Only databases No No Ribeiro et al., 2020 Yes Yes Not reported Only databases Yes No Bezerra et al., 2020 Yes Yes Not reported Unclear Yes Yes Dias et al., 2020 No Yes Not reported Both Yes Yes