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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
371

Méta-analyses des caractéristiques musculaires afin de prédire la tendreté de la viande bovine / Meta-analysis of muscle characteristics to predict beef tenderness

Chriki, Sghaïer 29 January 2013 (has links)
Un des enjeux de la filière bovine est la maîtrise et la prédiction de la tendreté de la viande, critère important pour les consommateurs. Inscrite dans le programme européen ProSafeBeef, ma thèse avait pour objectif de mieux prédire la tendreté par méta-analyse à partir des caractéristiques biochimiques du muscle. Pour cela, mon travail de thèse s’est appuyé sur la base de données BIF-Beef regroupant des données individuelles issues de plusieurs programmes de recherche, allant de l’animal à la viande en passant par la carcasse et le muscle. Une première méta-analyse a montré que le muscle Semitendinosus (ST) est de type plus rapide glycolytique que le Longissimus thoracis (LT) chez les mâles entiers et les femelles mais pas chez les mâles castrés. Après avoir identifié par une approche par classe de tendreté les caractéristiques musculaires associées à la tendreté, nous avons montré que ces caractéristiques sont différentes entre muscles et types d’animaux. Dans le muscle LT des taurillons, la surface moyenne des fibres musculaires est la variable qui joue le principal rôle sur la tendreté sensorielle où elle explique 2% de la variabilité des notes de tendreté. Principalement dans le muscle ST, les teneurs en collagène total et insoluble et l’activité enzymatique du métabolisme glycolytique expliquent au plus 6% chacun de la variabilité de la force de cisaillement. Malgré ces faibles parts de variabilité expliquée de la tendreté, ces conclusions validées sur un grand volume de données sont importantes pour préparer de nouveaux projets visant à compléter cette démarche en prenant en compte d’autres caractéristiques telles que des biomarqueurs génomiques. / The control of beef tenderness is essential for beef producers and retailers to deliver a consistently high quality product to consumers. Being part of the European program ProSafeBeef, my thesis aimed to predict beef tenderness by meta-analysis approaches using biochemical characteristics of muscles. To achieve this goal, we used data available in the BIF-Beef data warehouse which contains animal, carcass, muscle and meat measurements from different research programs. From available data on Longissimus thoracis (LT) and Semitendinosus (ST) muscles, we demonstrated that ST was faster and more glycolytic than LT in both entire males and females but not in steers. With a cluster analysis, we identified muscle biochemical traits associated with meat tenderness. Then, we demonstrated that no specific muscle biochemical characteristic can be a predictor of tenderness for all muscles and animal types. In LT muscle of young bulls, mean muscle fibre area explained 2% of the variability in sensory tenderness score. Mainly in ST muscle, total and insoluble collagen content and enzymatic indicators of glycolytic metabolism each explained about 6% of the variation in shear force. Although we were only able to explain a relatively small proportion of the total variance in tenderness, these results will form an important basis for the design of future experiments and the identification of new genomic markers of tenderness to be combined with muscle biochemistry in order to better predict beef quality.
372

The Price Elasticity of the Demand for Higher Education: A Meta-Analysis / The Price Elasticity of the Demand for Higher Education: A Meta-Analysis

Kiiashko, Olesia January 2016 (has links)
The main question of this study is whether the demand for higher education is relatively sensitive to tuition fee changes or is price inelastic. There is no definite answer in the literature. Approximately 52% of the estimates show it to be insignificant, 43% rate it as statistically negative, and approximately 5% are statistically positive. In a quantitative survey of 562 estimates reported in 48 studies, it has been found that large increases in tuition fees have a disproportionately negative impact on enrollment when potential publication bias and method heterogeneity are taken into account. The publication bias tests show that negative results are more preferable among researchers, because it is well supported by theory (when prices increase demand decreases). The results also suggest that four aspects of study design are especially effective in explaining the differences across primary studies: (1) the longer time period negatively associated with the price c of demand for higher education, (2) while the cross sectional estimations have reported more negative results, panel data estimations have reported fewer negative results, (3) controlling for endogeneity is crucial, (4) while controlling for unemployment rate has no clear conclusive impact, controlling for income is not significantly...
373

Histoire naturelle de la maladie rénale : Analyse des facteurs physiopathologiques et évaluation pronostique de l’insuffisance rénale terminale et de ses complications / Natural history of chronic kidney disease : Analysis of pathophysiological and prognostic factors of renal failure and its complications

Duranton, Flore 17 December 2013 (has links)
L'insuffisance rénale chronique (IRC) et son stade terminal sont associés à diverses complications, parmi lesquelles de nombreuses modifications du milieu intérieur : urémie, anémie, hyperparathyroïdie, rétention urémique… Les taux d'urée plasmatique ont longtemps été utilisés comme critère diagnostique de l'IRC, malgré l'absence de caractéristiques essentielles à un tel marqueur. Ces caractéristiques ont été discutées au regard de l'utilisation historique des déterminations d'urée. La caractérisation des altérations plasmatiques des patients en IRC est essentielle à la compréhension de la maladie et de leur lien avec la morbi-mortalité. Nous avons alors étendu notre champ d'intérêt à l'ensemble des solutés de rétention urémique, et sommes parvenus à identifier 56 nouveaux solutés à partir des études cliniques récemment publiées. L'évaluation diagnostique s'est poursuivie par l'étude des concentrations plasmatiques et urinaires en acides aminés et de leur association avec le stade d'IRC et ses complications, permettant alors la génération d'hypothèses sur l'origine métabolique de ces altérations. D'autre part, la mise en place d'une méta-analyse à montré une réduction du risque de décès chez les patients traités par dérivés de la vitamine D. La correction des comorbidités (hypovitaminose, perturbations du métabolisme phosphocalcique) et d'autres effets néphroprotecteurs expliqueraient ces bénéfices. Enfin, l'évaluation du protéome urinaire et du score CKD273 qui en résulte s'est avérée très intéressante pour l'identification des patients à risque de progresser, ce qui est un enjeu de santé publique. Ces travaux d'analyse bibliographique et de recherche clinique s'intègrent dans une volonté d'amélioration de la caractérisation de l'IRC et de l'évaluation de sa progression dans le but de prévenir ses complications. Ils sont le socle d'un projet plus large d'observation et d'analyse des caractéristiques des patients en IRC et de leur évolution. / Chronic kidney disease (CKD) and end-stage renal disease (ESRD) are associated with various complications, many of which occur within the internal environment: uremia, anemia, hyperparathyroidism, uremic retention… Plasma urea concentrations have long been used as a diagnostic criterion of CKD, despite the absence of some key characteristics. We discussed these features with regards to the historical uses of urea determinations. It is essential to characterize the plasma changes which occur in CKD to understand the disease and the relationship with comorbidities. We expanded our focus to all of uremic retention solutes, and identified 56 new solutes from recently published clinical studies. The study of plasma and urinary concentrations of amino acids and their association with CKD stage and complications further extended the study of CKD diagnosis, and allowed to generate hypotheses on the metabolic origin of these alterations. On the other hand, by meta-analysis, we showed a reduced risk of death in patients treated with vitamin D derivatives. Correcting comorbidities (hypovitaminosis, disturbances of bone and mineral metabolism) and other renoprotective effects may explain these benefits. Finally, the determination of the urinary proteome and the resulting CKD273 score was proved to be very useful for identifying patients at risk of progression, which is a public health issue. This work based on clinical research and literature analyses is part of an effort to improve the characterization of CKD and the evaluation of progression in order to avoid complications. It is the basis for a wider observational project: analyzing the characteristics of CKD patients and their changes over time.
374

Modern Econometric Techniques Applied To Three Essays In Spatial Economics

Fang, Fang, Fang, Fang January 2016 (has links)
For Chapter 1: This paper offers a meta-regression analysis of the controversial impact of EU structural funds on the growth of the recipient regions. It identifies the factors that explain the heterogeneity in the size of 323 estimates of their impact recorded in 17 econometric studies. Heterogeneity comes from the publication status, the period examined, controlling for endogeneity, from the presence of several regressors but not from differences in functional forms. For Chapter 2: Recent spatial econometric contributions call for theory-driven spatial models and W matrices capturing actual and time-varying interregional linkages. This paper answers this call by developing theoretically Griliches' well-known knowledge production function to add knowledge externalities to it. They capture how human and private capital originating from one region benefit the creation of innovation elsewhere. Furthermore, we measure interregional interaction based on the actual flows of patent creation-citation and of migration of the educated workers. They have the advantage of capturing clearly the direction of the knowledge transfers. Their presence in the theoretical model leads to a reduced-form spatial cross-regressive model which differentiates better the role of each type of externality - and displays a better goodness of fit - than the spatially lagged model where spillovers depend on geographical proximity only. Both models are estimated on spatial panel data covering the dynamics of innovation across US states over the 1986-1999 period. For Chapter 3: The Ricardian framework is increasingly used for the study of the impact of climate change on farmland values. While most of the Ricardian studies assume no interaction between the geographical units under study, the few that do rely on traditional proximity-based dependence. In this paper we argue that since the larger share of agricultural goods produced by a state is not for its own local market, including interregional trade in the Ricardian framework provides new perspectives, avoids a missing variable bias and prevents erroneous conclusions. Our new framework is applied to the system of the U.S. states over the four most recent censuses (1997-2012) and demonstrate that climate and socio-economic conditions experienced in a state's trade partners have a significant role on that state's local farmland values.
375

Adoption process of information technology (IT) innovations in organizations

Abdul Hameed, Mumtaz January 2012 (has links)
Several models have been developed for understanding and predicting innovation adoption in organizations and literature has identified several factors that impact the adoption and implementation of Information Technology (IT). This research examines the process of adoption of IT innovations in organizations. The study explores the processes involved in the adoption of IT and verifies the key factors that influence IT innovation adoption in organizations. Using a systematic literature review, the study developed a conceptual model of IT innovation adoption in organizations. The model is a theoretical combination of Diffusion of Innovation (DOI) theory, Theory of Reasoned Action (TRA), Technology Acceptance Model (TAM), Theory of Planned Behaviour (TPB) and a framework which contains characteristics of innovation, organization, environment, chief executive officer (CEO) and user acceptance. The model represents IT innovation adoption as a stage-based process, progressing from initiation to adoption-decision to implementation. The study aggregated findings of past research on IT adoption to identify key factors that influences IT adoption in organizations. The study performed a meta-analysis of innovation, organization, environment, CEOs and user acceptance determinants to assess the magnitude and the strength of these factors on IT innovation adoption. Results confirmed that relative advantage, compatibility, cost, observability and trialability are strong determinants of IT innovation adoption. In terms of organizational context, IS department size, top management support, organizational size, IT expertise, product champion, IS infrastructure, information intensity, resources and specialization was found influential in the adoption of IT. As for environmental characteristics, the meta-analysis verified the significance of external pressure, government support and competitive pressure. Meta-analysis results verified that CEO‟s innovativeness, attitude and IT knowledge as key determinants. The findings confirmed the importance of perceived usefulness, perceived ease of use, subjective norm and facilitating conditions for the user acceptance of IT in organizations.
376

Social Outcome Following Pediatric Traumatic Brain Injury: A Meta-Analysis

Mietchen, Jonathan James 01 June 2018 (has links)
Objective: Children and adolescents with a history of traumatic brain injury (TBI) are at increased risk for developing social incompetence and impairment in broad psychosocial functioning. The aim of this study was to examine the relationship between history of TBI, social competence, and broad psychosocial functioning using meta-analytic methods. Methods: Studies relating to social outcome following pediatric TBI were searched for using scientific, academic databases. Sixteen studies (N=2,005) met inclusion criteria, and relevant data relating to social functioning was extracted. Meta-analytic methods were used in order to obtain Hedges's g effect size data for mild, moderate, and severe TBI groups. Meta-regressions were also used to examine the effect of potential moderating variables, including Glasgow Coma Scale (GCS), socioeconomic status (SES), gender, control group (typically developing (TD) or orthopedic injury (OI)), and time/age related variables. Finally, publication bias was calculated using funnel plots and Rosenthal's fail-safe N. Results: A dose-response effect was observed with mild (Hedges's g = -0.387), and moderate (Hedges's g = -0.459) groups demonstrating smaller effects when compared to the severe group (-0.814) on measures of broad psychosocial function. A dose-response effect was also observed on measures of social competence, with mild (Hedges's g = -0.098) and moderate (Hedges's g = -0.450) TBI groups demonstrating smaller effect sizes when compared to the severe TBI group (Hedges's g = -0.832). The GCS was a significant predictor of both broad psychosocial functioning (B = 0.065, p < 0.001) and social competence (B = 0.079, p < 0.001), such that more severe injuries predicted poorer social outcomes. Gender was a significant predictor of effect size (B = 0.018, p = 0.05), such that higher proportions of females was associated with smaller effect sizes. Finally, the type of control group used in these studies was also a significant predictor of effect size (B = 0.369, p = 0.03), such that studies that used TD produced larger effect sizes when compared to studies that used OI. Overall, there was little evidence for publication bias. Conclusions: Children and adolescents with a history of TBI demonstrated significant differences from their peers in social competence and broad psychosocial functioning following TBI. The severity of the injury is important in understanding and predicting social outcomes following pediatric TBI. Implications of these findings are discussed.
377

Triklosanbelagda suturers förebyggande effekt mot postoperativa sårinfektioner : En systematisk litteraturstudie med metaanalys

Manneklint, Anna January 2019 (has links)
Bakgrund: Postoperativa sårinfektioner drabbar ca 2,3 % av de patienter som genomgått ett kirurgiskt ingrepp i svensk hälso- och sjukvård. Dessa infektioner kan ge upphov till förlängd vårdtid, ytterligare kirurgiska ingrepp och ökad mortalitet. Postoperativa sårinfektioner innebär ett lidande för patienten samtidigt som det är kostsamt för sjukvården. Inom sjukvården används utarbetade arbetssätt för att minska riskerna för att patienten ska drabbas. Samtidigt utvecklas och studeras nya metoder i det preventiva arbetet mot postoperativa sårinfektioner, exempelvis suturer belagda med antibakteriella substanser. En av dessa är triklosanbelagda suturer. Dock råder viss oenighet om dess preventiva effekter och roll i det förebyggande arbetet mot postoperativa sårinfektioner. Syfte: Studiens syfte var att undersöka om suturer med beläggning av triklosan har en förebyggande effekt mot postoperativa sårinfektioner. Metod: Studien utformades som en systematisk litteraturstudie med metaanalys av 7 randomiserade kontrollerade studier. Dessa studier hade en uppföljningstid om 30 dagar samt använt bedömningskriterier för förekomst av postoperativa sårinfektioner enligt CDC, Centers for Disease Control and Prevention. Resultat: Inget statistiskt signifikant resultat kunde erhållas gällande triklosanbelagda suturers preventiva effekt mot postoperativa sårinfektioner. (RR=0,8, 95 % CI=0,63-1,02, p=0.07). Slutsats: Studien indikerar att triklosanbelagda suturer inte rutinmässigt bör användas i preventivt syfte mot postoperativa sårinfektioner. Ytterligare forskning behövs på området. / Background: Approximately 2,3 % of the patients undergoing surgery in Swedish healthcare develop surgical site infections. These infections are often associated with prolonged hospital stay, additional surgical procedures and increased mortality. Surgical site infections cause patient suffering and increase healthcare costs. In healthcare, standard guidelines and work methods are used to prevent patients from developing surgical site infections. New methods to reduce the risk of surgical site infections are being developed and studied, such as sutures with antibacterial coating. One of these is Triclosan-coated sutures. However, there is some disagreement on its preventive effects and role in reducing surgical site infections. Aim: The aim of this study was to investigate if Triclosan-coated sutures have a preventive effect against surgical site infections. Method: This study was conducted as a systematic literature review with meta-analysis of 7 RCT. These studies all had a follow up time of 30 days and used the criteria of CDC, Centers for Disease Control and Prevention, to identify surgical site infections. Result: This study showed no statistically significant results of Triclosan-coated sutures preventive effect against surgical site infections. (RR=0,8, 95 % CI=0,63-1,02, p=0.07). Conclusion: This study indicates that Triclosan-coated sutures should not be used routinely to prevent surgical site infections. More studies are needed.
378

A Meta-analysis of School Counselor-led Interventions on Social-emotional Skills and Competence for Middle and High School Students

Unknown Date (has links)
This meta-analysis investigated the practical significance of school counselor-led social emotional learning (SEL) interventions on outcomes for students in Grades 6–12. The sample includes 28 studies involving 3,794 middle and high school students. The treatment group was comprised of a total of 2,032 students, who received interventions led by a certified school counselor. The control/comparison groups were derived from a sample of 1,762 middle and high school students who did not receive the school counselor-led intervention. The meta-analysis included a diverse sample of students, with ethnicity reported as 589 (15.52%) African American, 52 (1.37%) Asian, 1,162 (30.63%) Hispanic, 1,267 (33.39%) Caucasian, 11 (0.28%) Native American, 21 (0.55%) Pacific Islander, and 177 (4.66%) Multi-racial/Other. Of the studies included in the meta-analysis, the ethnicities of 412 (18.86%) students were not reported. A total of 12 studies were conducted at the middle school level, 10 at the high school level, and 6 studies reported a mixed setting of Grades 6–12. The sample included almost equal representation of 1,883 (49.63%) males and 1,847 (48.68%) females, and the genders of 69 (1.82%) students were not reported. The overall unweighted Cohen’s d effect size (ES) of the school counselor-led interventions was .312 (95% CI [.173, .452]). The ES for overall cognitive outcomes (d = 0.380) was slightly larger than for overall effective role functions outcomes (d =0.377) and affective outcomes (d = 0.356). The smallest ES reported for overall variables was for behavioral outcomes (d = 0.228). The largest ES for a specific student outcome measure was found for standardized achievement test scores (d = 0.612) (Vernez & Zimmer, 2007). Moderator analyses were conducted and are explored in the results and discussion. The results address the current gap in school counseling outcome research by broadening future research directions for comprehensive school counseling programs (CSCP) to incorporate SEL initiatives aimed for middle and high school students. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection
379

Produ??o cient?fica sobre o idoso na psycrnFO (2003) / Scientific Production about lhe old aged person in the PsycJNFO (2003)

Ferreira, Adriana Aparecida 14 December 2004 (has links)
Made available in DSpace on 2016-04-04T18:28:01Z (GMT). No. of bitstreams: 1 Adriana Ap Ferreira 1.pdf: 2671092 bytes, checksum: 52bffd7181072105e7e3c13a4ab6f2c7 (MD5) Previous issue date: 2004-12-14 / With the increse of longevity and consequently the increase of scientific production about old age, it is necessary one analysis of the area's done knowledge. It was done a meta-analysis of the studies produced in the psychology area about old aged persons, in the PsycINFO database, on the first semester of 2003 (N=1281). It was analyzed: title, authors, type of work, themes, participants, reserch place, material used for data collection, and focus. In general, the titles presented a number of words within the recommended quantity, in 42,89% punctuation was not used and in 34,76% it was used colons. The authorship was predominantly multiple (90,1%), with majority male production. The reserch production is predominant (98,75%), and scientific journal is the most used vehicle for divulgation (98,4%). The most frequent themes were Social/Cultural Aspects, Psychological Aspects/ Chsrecte ristics and Diseases; there was a correlation botween the themes classified for the database anf the authors (r=0,98). The majorith of the studies compares old and adilt persons. America and Europe were the continents of major production. The majority of works were made in Health Services (37,71%) in which several types of instruments were used for data collection. The difference between the focus loss (21%) and gain (13,82%) was significant statistically. It is concluded that the area shows development signs. / Com o aumento da longevidade e conseq?ente aumento da produ??o cient?fica sobre velhice, faz-se necess?ria uma an?lise do conhecimento gerado na ?rea. Foi feita uma meta-an?lise dos estudos realizados na ?rea de psicologia sobre idosos, inseridos na base de dados PsyclNFO, no primeiro semestre de 2003 (N=1281). Foram analisados: t?tulo, autoria, tipo de trabalho, tem?tica, participantes, locais de realiza??o das pesquisas, materiais usados para a coleta de dados e enfoque. No geral, os t?tulos apresentaram n?mero de voc?bulos dentro do recomendado, sendo que em 42,89% n?o foi feito uso de pontua??o e em 34,76% foi utilizado dois pontos. A autoria foi predominantemente m?ltipla (90,1%), com maior produ??o mascul ina. A produ??o de pesquisas ? predominante (98,75%), sendo o peri?dico cient?fico o ve?culo mais utilizado para divulga??o (98,4%). Os temas mais freq?entes foram Aspectos Sociais! Culturais, Aspectos! Caracter?sticas Psicol?gicas e Doen?as; houve correla??o entre a classifica??o feita pela base e pelos autores (r=0,98). A maioria dos estudos compara idosos e pessoas adultas. Am?rica e Europa foram os cont?nentes de maior produ??o. A maioria dos trabalhos foi realizada em Servi?os de Sa?de (37,71 %), tendo sido usados v?rios tipos de instrumentos para a coleta dos dados. A diferen?a entre o enfoque perda (21 %) e ganho (13,82%) foi estatisticamente significante. Conclui-se que a ?rea mostra sinais de desenvolvimento.
380

Performance dos métodos visual, radiográfico e baseados em fluorescência na detecção de lesões de cárie: revisões sistemáticas com meta-análises e investigações de fontes de heterogeneidade / Performance of visual, radiographic and fluorescence based methods in detecting carious lesions: systematic reviews, meta-analyses and investigation of sources of heterogeneity

Cóvos, Thais Gimenez 13 May 2016 (has links)
O presente estudo teve como objetivo avaliar a performance dos métodos visual, radiográfico e baseados em fluorescência quanto à detecção de lesões de cárie em dentes permanentes e decíduos, realizar meta-análise com a performance global dos métodos e investigar as possíveis fontes de heterogeneidades. Foram realizadas três revisões distintas relacionadas a cada método diagnóstico. Quatro examinadores avaliaram os trabalhos, sendo pelo menos dois por método. Estes efetuaram a busca e seleção de artigos de modo independente; um pesquisador com experiência em trabalhos de diagnóstico de cárie resolveu os casos de conflito ou dúvida. As bases de dados eletrônicas utilizadas foram MEDLINE, EMBASE e Scopus, visando reduzir o viés de publicação, também foram buscados trabalhos acadêmicos e documentos não publicados, através do OpenSigle e Anais do Congresso ORCA. Após a seleção dos estudos por critérios de inclusão e exclusão bem definidos, os dados foram coletados e anotados, de maneira independente por cada revisor. Foi realizada a avaliação da qualidade metodológica através da ferramenta Quality Assessment of Diagnostic Accuracy Studies (QUADAS) e a análise estatística através do Paired Forest Plot, Summary Receiver Operating Characteristics analysis (SROC), relative diagnostic odds ratio (RDOR), análise de sensibilidade e gráfico de funil, além da investigação e exploração das possíveis fontes de heterogeneidade. Para o método visual, 102 artigos preencheram os critérios de inclusão. Em geral, a análise demonstrou que o método visual teve uma boa acurácia para a detecção de lesões de cárie. Embora estudos laboratoriais e clínicos tenham apresentado acurácias semelhantes, os valores de especificidade obtidos clinicamente foram maiores. Observamos, também, moderada a elevada heterogeneidade e evidência de viés de publicação na maioria dos estudos. Além disso, o uso de sistemas de escores visual resultaram em valores significativamente melhores de acurácia em comparação com estudos que utilizaram os seus próprios critérios. Quanto à relevância clínica dos estudos de acurácia do método visual, 96 estudos foram incluídos. Em geral, a maioria dos estudos falha em considerar alguns aspectos clínicos relevantes: somente 1 estudo incluiu avaliação da atividade das lesões; nenhum estudo considerou o seu prognóstico; 79 estudos não consideraram um desfecho clínico relevante e apenas 1 avaliou um desfecho centrado no paciente. Quanto à qualidade metodológica, a maioria dos estudos presentes apresentou alto risco de viés na seleção da amostra. Quanto ao método radiográfico, 116 artigos foram selecionados. Os métodos radiográficos convencional e digital apresentaram desempenho semelhante, mostrando valores maiores de especificidade comparados aos de sensibilidade, além de maiores valores de AUC no limiar de lesões mais avançadas. Quanto aos métodos baseados em fluorescência, 75 estudos preencheram os critérios de inclusão. Em geral, a análise demonstrou uma tendência a valores de acurácia semelhantes para todos os tipos de dentes, superfícies ou tipos de estudo. Houve uma tendência de melhor desempenho na detecção de lesões de cárie mais avançadas. Observamos, também, moderada a alta heterogeneidade e evidência de viés de publicação. Em conclusão, o método visual de detecção de lesões de cárie tem um bom desempenho geral, mas os estudos deveriam considerar desfechos clínicos relevantes, além da acurácia. Além disso, eles deveriam ser conduzidos com maior qualidade metodológica, principalmente em relação à seleção da amostra. Ainda, a utilização de índices detalhados e validados parece melhorar a acurácia do método. O método radiográfico não apresentou diferença entre os modos de aquisição de imagem (digital ou convencional), demonstrando uma tendência a valores superiores de especificidade e melhor desempenho em lesões avançadas. Quanto aos dispositivos baseados em fluorescência, estes mostraram desempenho global semelhante; no entanto, uma melhor acurácia na detecção de lesões de cárie mais avançadas tem sido observada. / This study aimed to evaluate the performance of visual, radiographic and fluorescence-based methods in the detection of caries lesions in permanent and primary teeth, to perform meta-analysis of the overall performance of the methods and to investigate possible sources of heterogeneity. Three distinct systematic reviews related to each diagnostic method were performed. Four observers evaluated the articles, at least two per method. They performed the search and study selection independently; a researcher with experience in caries diagnostic studies solved the cases of conflict or doubt. Electronic databases used were MEDLINE, EMBASE and Scopus, to reduce publication bias, were also pursued academic papers and unpublished documents through OpenSigle and the Annals of ORCA Congress. After the selection of studies by well-defined inclusion and exclusion criteria, data were collected and recorded, independently by each reviewer. Methodological quality assessment was performed through Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS) and statistical analysis using Paired Forest Plot, Summary Receiver Operating Characteristics analysis (SROC), relative diagnostic odds ratio (RDOR), sensitivity analysis and funnel plot, in addition we explored possible sources of heterogeneity. Regarding the accuracy of visual method, 102 articles met the inclusion criteria. In general, visual analysis showed that the method had a good accuracy in the detection of caries lesions. Although laboratory and clinical studies have shown similar accuracies, clinical studies have obtained higher specificities. We also observed moderate to high heterogeneity and evidence of publication bias in most studies. In addition, the use of visual scoring systems resulted in significantly better accuracy compared to studies using their own criteria. Concerning the clinical relevance of accuracy studies of visual method, 96 studies were included. In general, most studies failed to consider some relevant clinical aspects: only 1 study included assessment of activity of the lesions; no study considered their prognosis; 79 studies did not consider a relevant clinical outcome and only 1 evaluated a patient-centered outcome. With regard to the methodological quality, most of the present studies showed a high risk of bias in the selection of the sample. With concern to the radiographic method, 116 articles were selected. Conventional and digital radiographic methods showed similar performance, showing greater specificity values compared to sensitivity, and higher AUC values at the threshold of more advanced caries lesions. Regarding fluorescence-based methods, 75 studies met the inclusion criteria. In general, the analysis demonstrated that the fluorescence-based method tend to have similar accuracy for all types of teeth, dental surfaces or settings. There was a trend of better performance of fluorescence methods in detecting more advanced caries lesions. We also observed moderate to high heterogeneity and evidenced publication bias. In conclusion, the visual method of detecting caries lesions has a good overall performance, but studies should consider relevant clinical outcomes, as well as accuracy. In addition, they should be conducted with greater methodological quality, especially in relation to sample selection. Still, the use of detailed and validated indices seems to improve the accuracy of the method. Radiographic method showed no difference between the image acquisition modes (digital or conventional), showing a tendency to higher values of specificity and performance in advanced caries lesions. Fluorescence-based devices showed similar overall performance; however, a better accuracy in detecting more advanced caries has been observed.

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