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1.
Cochrane Database Syst Rev ; 6: CD010296, 2017 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-28598495

RESUMO

BACKGROUND: People with abdominal aortic aneurysm who receive endovascular aneurysm repair (EVAR) need lifetime surveillance to detect potential endoleaks. Endoleak is defined as persistent blood flow within the aneurysm sac following EVAR. Computed tomography (CT) angiography is considered the reference standard for endoleak surveillance. Colour duplex ultrasound (CDUS) and contrast-enhanced CDUS (CE-CDUS) are less invasive but considered less accurate than CT. OBJECTIVES: To determine the diagnostic accuracy of colour duplex ultrasound (CDUS) and contrast-enhanced-colour duplex ultrasound (CE-CDUS) in terms of sensitivity and specificity for endoleak detection after endoluminal abdominal aortic aneurysm repair (EVAR). SEARCH METHODS: We searched MEDLINE, Embase, LILACS, ISI Conference Proceedings, Zetoc, and trial registries in June 2016 without language restrictions and without use of filters to maximize sensitivity. SELECTION CRITERIA: Any cross-sectional diagnostic study evaluating participants who received EVAR by both ultrasound (with or without contrast) and CT scan assessed at regular intervals. DATA COLLECTION AND ANALYSIS: Two pairs of review authors independently extracted data and assessed quality of included studies using the QUADAS 1 tool. A third review author resolved discrepancies. The unit of analysis was number of participants for the primary analysis and number of scans performed for the secondary analysis. We carried out a meta-analysis to estimate sensitivity and specificity of CDUS or CE-CDUS using a bivariate model. We analysed each index test separately. As potential sources of heterogeneity, we explored year of publication, characteristics of included participants (age and gender), direction of the study (retrospective, prospective), country of origin, number of CDUS operators, and ultrasound manufacturer. MAIN RESULTS: We identified 42 primary studies with 4220 participants. Twenty studies provided accuracy data based on the number of individual participants (seven of which provided data with and without the use of contrast). Sixteen of these studies evaluated the accuracy of CDUS. These studies were generally of moderate to low quality: only three studies fulfilled all the QUADAS items; in six (40%) of the studies, the delay between the tests was unclear or longer than four weeks; in eight (50%), the blinding of either the index test or the reference standard was not clearly reported or was not performed; and in two studies (12%), the interpretation of the reference standard was not clearly reported. Eleven studies evaluated the accuracy of CE-CDUS. These studies were of better quality than the CDUS studies: five (45%) studies fulfilled all the QUADAS items; four (36%) did not report clearly the blinding interpretation of the reference standard; and two (18%) did not clearly report the delay between the two tests.Based on the bivariate model, the summary estimates for CDUS were 0.82 (95% confidence interval (CI) 0.66 to 0.91) for sensitivity and 0.93 (95% CI 0.87 to 0.96) for specificity whereas for CE-CDUS the estimates were 0.94 (95% CI 0.85 to 0.98) for sensitivity and 0.95 (95% CI 0.90 to 0.98) for specificity. Regression analysis showed that CE-CDUS was superior to CDUS in terms of sensitivity (LR Chi2 = 5.08, 1 degree of freedom (df); P = 0.0242 for model improvement).Seven studies provided estimates before and after administration of contrast. Sensitivity before contrast was 0.67 (95% CI 0.47 to 0.83) and after contrast was 0.97 (95% CI 0.92 to 0.99). The improvement in sensitivity with of contrast use was statistically significant (LR Chi2 = 13.47, 1 df; P = 0.0002 for model improvement).Regression testing showed evidence of statistically significant effect bias related to year of publication and study quality within individual participants based CDUS studies. Sensitivity estimates were higher in the studies published before 2006 than the estimates obtained from studies published in 2006 or later (P < 0.001); and studies judged as low/unclear quality provided higher estimates in sensitivity. When regression testing was applied to the individual based CE-CDUS studies, none of the items, namely direction of the study design, quality, and age, were identified as a source of heterogeneity.Twenty-two studies provided accuracy data based on number of scans performed (of which four provided data with and without the use of contrast). Analysis of the studies that provided scan based data showed similar results. Summary estimates for CDUS (18 studies) showed 0.72 (95% CI 0.55 to 0.85) for sensitivity and 0.95 (95% CI 0.90 to 0.96) for specificity whereas summary estimates for CE-CDUS (eight studies) were 0.91 (95% CI 0.68 to 0.98) for sensitivity and 0.89 (95% CI 0.71 to 0.96) for specificity. AUTHORS' CONCLUSIONS: This review demonstrates that both ultrasound modalities (with or without contrast) showed high specificity. For ruling in endoleaks, CE-CDUS appears superior to CDUS. In an endoleak surveillance programme CE-CDUS can be introduced as a routine diagnostic modality followed by CT scan only when the ultrasound is positive to establish the type of endoleak and the subsequent therapeutic management.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Meios de Contraste , Endoleak/diagnóstico por imagem , Procedimentos Endovasculares , Ultrassonografia Doppler Dupla , Feminino , Humanos , Masculino , Sensibilidade e Especificidade , Stents/estatística & dados numéricos , Tomografia Computadorizada por Raios X
2.
J Clin Epidemiol ; 84: 37-46, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28088592

RESUMO

OBJECTIVES: To describe the characteristics, and estimate the incidence, of trials included in systematic reviews deviating from the intention-to-treat (ITT) principle. STUDY DESIGN AND SETTING: A 5% random sample of reviews were selected (Medline 2006-2010). Trials from reviews were classified based on the ITT: (1) ITT trials (trials reporting standard ITT analyses); (2) modified ITT (mITT) trials (modified ITT; trials deviating from standard ITT); or (3) no ITT trials. RESULTS: Of 222 reviews, 81 (36%) included at least one mITT trial. Reviews with mITT trials were more likely to contain trials that used placebo, that investigated drugs, and that reported favorable results. The incidence of reviews with mITT trial ranged from 29% (17/58) to 48% (23/48). Of the 2,349 trials, 597 (25.4%) were classified as ITT trials, 323 (13.8%) as mITT trials, and 1,429 (60.8%) as no ITT trials. The mITT trials were more likely to have reported exclusions compared to studies classified as ITT trials and to have received funding. CONCLUSION: The reporting of the type of ITT may differ according to the clinical area and the type of intervention. Deviation from ITT in randomized controlled trials is a widespread phenomenon that significantly affects systematic reviews.


Assuntos
Análise de Intenção de Tratamento/estatística & dados numéricos , Literatura de Revisão como Assunto , Humanos , MEDLINE , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos
3.
BMJ Open ; 6(9): e011776, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27633635

RESUMO

INTRODUCTION: Administrative healthcare databases are useful to investigate the epidemiology, health outcomes, quality indicators and healthcare utilisation concerning peptic ulcers and gastrointestinal bleeding, but the databases need to be validated in order to be a reliable source for research. The aim of this protocol is to perform the first systematic review of studies reporting the validation of International Classification of Diseases, 9th Revision and 10th version (ICD-9 and ICD-10) codes for peptic ulcer and upper gastrointestinal bleeding diagnoses. METHODS AND ANALYSIS: MEDLINE, EMBASE, Web of Science and the Cochrane Library databases will be searched, using appropriate search strategies. We will include validation studies that used administrative data to identify peptic ulcer disease and upper gastrointestinal bleeding diagnoses or studies that evaluated the validity of peptic ulcer and upper gastrointestinal bleeding codes in administrative data. The following inclusion criteria will be used: (a) the presence of a reference standard case definition for the diseases of interest; (b) the presence of at least one test measure (eg, sensitivity, etc) and (c) the use of an administrative database as a source of data. Pairs of reviewers will independently abstract data using standardised forms and will evaluate quality using the checklist of the Standards for Reporting of Diagnostic Accuracy (STARD) criteria. This systematic review protocol has been produced in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocol (PRISMA-P) 2015 statement. ETHICS AND DISSEMINATION: Ethics approval is not required given that this is a protocol for a systematic review. We will submit results of this study to a peer-reviewed journal for publication. The results will serve as a guide for researchers validating administrative healthcare databases to determine appropriate case definitions for peptic ulcer disease and upper gastrointestinal bleeding, as well as to perform outcome research using administrative healthcare databases of these conditions. TRIAL REGISTRATION NUMBER: CRD42015029216.


Assuntos
Confiabilidade dos Dados , Bases de Dados Factuais , Hemorragia Gastrointestinal/diagnóstico , Classificação Internacional de Doenças , Úlcera Péptica/diagnóstico , Estudos de Validação como Assunto , Lista de Checagem , Humanos , Padrões de Referência , Projetos de Pesquisa , Revisões Sistemáticas como Assunto
4.
BMJ Open ; 6(6): e011777, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27251687

RESUMO

INTRODUCTION: Healthcare databases are useful sources to investigate the epidemiology of chronic obstructive pulmonary disease (COPD), to assess longitudinal outcomes in patients with COPD, and to develop disease management strategies. However, in order to constitute a reliable source for research, healthcare databases need to be validated. The aim of this protocol is to perform the first systematic review of studies reporting the validation of codes related to COPD diagnoses in healthcare databases. METHODS AND ANALYSIS: MEDLINE, EMBASE, Web of Science and the Cochrane Library databases will be searched using appropriate search strategies. Studies that evaluated the validity of COPD codes (such as the International Classification of Diseases 9th Revision and 10th Revision system; the Real codes system or the International Classification of Primary Care) in healthcare databases will be included. Inclusion criteria will be: (1) the presence of a reference standard case definition for COPD; (2) the presence of at least one test measure (eg, sensitivity, positive predictive values, etc); and (3) the use of a healthcare database (including administrative claims databases, electronic healthcare databases or COPD registries) as a data source. Pairs of reviewers will independently abstract data using standardised forms and will assess quality using a checklist based on the Standards for Reporting of Diagnostic accuracy (STARD) criteria. This systematic review protocol has been produced in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocol (PRISMA-P) 2015 statement. ETHICS AND DISSEMINATION: Ethics approval is not required. Results of this study will be submitted to a peer-reviewed journal for publication. The results from this systematic review will be used for outcome research on COPD and will serve as a guide to identify appropriate case definitions of COPD, and reference standards, for researchers involved in validating healthcare databases. TRIAL REGISTRATION NUMBER: CRD42015029204.


Assuntos
Codificação Clínica/normas , Bases de Dados Factuais , Atenção à Saúde/normas , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Gerenciamento Clínico , Humanos , Classificação Internacional de Doenças , Projetos de Pesquisa , Revisões Sistemáticas como Assunto , Estudos de Validação como Assunto
5.
BMJ ; 350: h2445, 2015 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-26016488

RESUMO

OBJECTIVE: To examine whether deviation from the standard intention to treat analysis has an influence on treatment effect estimates of randomised trials. DESIGN: Meta-epidemiological study. DATA SOURCES: Medline, via PubMed, searched between 2006 and 2010; 43 systematic reviews of interventions and 310 randomised trials were included. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: From each year searched, random selection of 5% of intervention reviews with a meta-analysis that included at least one trial that deviated from the standard intention to treat approach. Basic characteristics of the systematic reviews and randomised trials were extracted. Information on the reporting of intention to treat analysis, outcome data, risk of bias items, post-randomisation exclusions, and funding were extracted from each trial. Trials were classified as: ITT (reporting the standard intention to treat approach), mITT (reporting a deviation from the standard approach), and no ITT (reporting no approach). Within each meta-analysis, treatment effects were compared between mITT and ITT trials, and between mITT and no ITT trials. The ratio of odds ratios was calculated (value <1 indicated larger treatment effects in mITT trials than in other trial categories). RESULTS: 50 meta-analyses and 322 comparisons of randomised trials (from 84 ITT trials, 118 mITT trials, and 108 no ITT trials; 12 trials contributed twice to the analysis) were examined. Compared with ITT trials, mITT trials showed a larger intervention effect (pooled ratio of odds ratios 0.83 (95% confidence interval 0.71 to 0.96), P=0.01; between meta-analyses variance τ(2)=0.13). Adjustments for sample size, type of centre, funding, items of risk of bias, post-randomisation exclusions, and variance of log odds ratio yielded consistent results (0.80 (0.69 to 0.94), P=0.005; τ(2)=0.08). After exclusion of five influential studies, results remained consistent (0.85 (0.75 to 0.98); τ(2)=0.08). The comparison between mITT trials and no ITT trials showed no statistical difference between the two groups (adjusted ratio of odds ratios 0.92 (0.70 to 1.23); τ(2)=0.57). CONCLUSIONS: Trials that deviated from the intention to treat analysis showed larger intervention effects than trials that reported the standard approach. Where an intention to treat analysis is impossible to perform, authors should clearly report who is included in the analysis and attempt to perform multiple imputations.


Assuntos
Viés , Análise de Intenção de Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Epidemiológicos , Humanos , Razão de Chances , Resultado do Tratamento
6.
Trials ; 12: 58, 2011 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-21356072

RESUMO

BACKGROUND: Randomized controlled trials (RCTs) that use the modified intention-to-treat (mITT) approach are increasingly being published. Such trials have a preponderance of post-randomization exclusions, industry sponsorship, and favourable findings, and little is known whether in terms of these items mITT trials are different with respect to trials that report a standard intention-to-treat. METHODS: To determine differences in the methodological quality, sponsorship, authors' conflicts of interest, and findings among trials with different "types" of intention-to-treat, we undertook a cross-sectional study of RCTs published in 2006 in three general medical journals (the Journal of the American Medical Association, the New England Journal of Medicine and the Lancet) and three specialty journals (Antimicrobial Agents and Chemotherapy, the American Heart Journal and the Journal of Clinical Oncology). Trials were categorized based on the "type" of intention-to-treat reporting as follows: ITT, trials reporting the use of standard ITT approach; mITT, trials reporting the use of a "modified intention-to-treat" approach; and "no ITT", trials not reporting the use of any intention-to-treat approach. Two pairs of reviewers independently extracted the data in duplicate. The strength of the associations between the "type" of intention-to-treat reporting and the quality of reporting (sample size calculation, flow-chart, lost to follow-up), the methodological quality of the trials (sequence generation, allocation concealment, and blinding), the funding source, and the findings was determined. Odds ratios (OR) were calculated with 95% confidence intervals (CI). RESULTS: Of the 367 RCTs included, 197 were classified as ITT, 56 as mITT, and 114 as "no ITT" trials. The quality of reporting and the methodological quality of the mITT trials were similar to those of the ITT trials; however, the mITT trials were more likely to report post-randomization exclusions (adjusted OR 3.43 [95%CI, 1.70 to 6.95]; P < 0.001). We found a strong association between trials classified as mITT and for-profit agency sponsorship (adjusted OR 7.41 [95%CI, 3.14 to 17.48]; P < .001) as well as the presence of authors' conflicts of interest (adjusted OR 5.14 [95%CI, 2.12 to 12.48]; P < .001). There was no association between mITT reporting and favourable results; in general, however, trials with for-profit agency sponsorship were significantly associated with favourable results (adjusted OR 2.30; [95%CI, 1.28 to 4.16]; P = 0.006). CONCLUSION: We found that the mITT trials were significantly more likely to perform post-randomization exclusions and were strongly associated with industry funding and authors' conflicts of interest.


Assuntos
Conflito de Interesses , Indústria Farmacêutica/economia , Medicina Baseada em Evidências , Análise de Intenção de Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Apoio à Pesquisa como Assunto , Intervalos de Confiança , Estudos Transversais , Interpretação Estatística de Dados , Medicina Baseada em Evidências/economia , Medicina Baseada em Evidências/métodos , Medicina Baseada em Evidências/normas , Humanos , Razão de Chances , Ensaios Clínicos Controlados Aleatórios como Assunto/economia , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Projetos de Pesquisa/normas , Resultado do Tratamento
7.
Am J Hypertens ; 20(4): 443-50, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17386354

RESUMO

BACKGROUND: Oxidative inactivation of nitric oxide (NO) is regarded as an important cause of reduced endothelium-dependent vasodilation in essential hypertension. Because zofenopril, an angiotensin-converting enzyme (ACE) inhibitor with a sulfhydryl (SH) group, has demonstrated antioxidant properties and to reduce adhesion molecule expression in vitro, in this study we evaluated the effect of this drug in comparison with the carboxylic ACE inhibitor ramipril and the beta-adrenoreceptor blocker atenolol on (1) circulating adhesion molecules and some oxidative stress parameters and (2) endothelium-dependent vasodilation in essential mildly hypertensive patients. METHODS: A total of 45 healthy subjects and 45 matched hypertensive patients participated in the study. Hypertensive patients were randomly treated with zofenopril (15 to 30 mg/d), ramipril (2.5 to 5 mg/d), and atenolol (50 to 100 mg/d). At baseline and after an 8-week therapy we evaluated blood pressure (BP) values, plasma and LDL hydroperoxides, plasma 8-isoprostanes, circulating levels of oxidized-(ox)LDL and of adhesion molecules (intercellular cell adhesion molecule-1 [ICAM-1], and vascular cell adhesion molecule-1 [VCAM-1], and E-selectin). Furthermore, all patients underwent ultrasound detection of brachial artery reactivity and endothelium-dependent dilation (flow-mediated dilation, FMD) was evaluated. RESULTS: All the treatments determined similar significant (P < .001) reduction of both systolic and diastolic BP values. Plasma (P < .01) and LDL hydroperoxides (P < .01), plasma 8-isoprostanes (P < .05), circulating oxLDL (P < .05), and adhesion molecules (P < .05) were significantly reduced only in patients receiving zofenopril. Similarly FMD was significantly increased (P < .001) in the zofenopril-treated group. CONCLUSIONS: Our results suggest that in mildly hypertensive patients without organ damage zofenopril, beyond its BP-lowering effects and through its sustained antioxidant activity, offers important advantages in reducing endothelial activation.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Captopril/análogos & derivados , Endotélio Vascular/fisiopatologia , Hipertensão/tratamento farmacológico , Ramipril/uso terapêutico , Compostos de Sulfidrila/uso terapêutico , Antagonistas Adrenérgicos beta/farmacologia , Antagonistas Adrenérgicos beta/uso terapêutico , Adulto , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Atenolol/farmacologia , Atenolol/uso terapêutico , Glicemia/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Captopril/farmacologia , Captopril/uso terapêutico , Moléculas de Adesão Celular/sangue , Moléculas de Adesão Celular/efeitos dos fármacos , HDL-Colesterol/sangue , Endotélio Vascular/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Ramipril/farmacologia , Compostos de Sulfidrila/farmacologia , Triglicerídeos/sangue , Vasodilatação/efeitos dos fármacos
8.
Clin Infect Dis ; 38(4): 515-20, 2004 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-14765344

RESUMO

This case report describes a brother and a sister with severe meningoencephalitis caused by Toscana virus (TOSv). The clinical presentation was characterized by stiff neck, deep coma, maculopapular rash, diffuse lymphadenopathy, hepatosplenomegaly, renal involvement, tendency to bleeding, and diffuse intravascular coagulation. The boy had epididymo-orchitis. Recovery with neurologic sequelae as hydrocephalus was observed. Microbiological diagnosis was obtained by serological tests and reverse transcriptase-polymerase chain reaction. Sequencing of polymerase chain reaction products from the S and M segments was carried out. TOSv may be a causative agent in severe meningoencephalitis.


Assuntos
Meningoencefalite/fisiopatologia , Febre por Flebótomos/fisiopatologia , Vírus da Febre do Flebótomo Napolitano/isolamento & purificação , Adolescente , Adulto , Feminino , Humanos , Masculino , Meningoencefalite/virologia , Febre por Flebótomos/virologia , RNA Viral/análise , Vírus da Febre do Flebótomo Napolitano/genética , Vírus da Febre do Flebótomo Napolitano/imunologia , Testes Sorológicos
9.
J Neurovirol ; 10(6): 414-7, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15765813

RESUMO

Epstein-Barr Virus (EBV) encephalitis is a rare (<1%) and generally self-limited disease with few sequelae. This neurological complication has been reported almost exclusively in the course of acute primary infection and in paediatric patients. We describe a case of a young adult immunocompetent man who developed an acute fatal necrotizing haemorrhagic encephalitis as the only manifestation of an acute EBV infection. EBV-DNA was tested positive in several CSF samples by qualitative and quantitative PCR. Serological profile showed: absence of IgM against Viral Capsid Antigen (VCA) in three different consecutive samples, presence of IgG against VCA and IgG seroconversion for Epstein Barr Nuclear Antigen (EBNA). EBV-DNA was detected by qualitative PCR in autoptic brain material. Clinical course was not influenced by antiviral therapy with acyclovir. In conclusion to our knowledge, this is the only case of acute necrotizing haemorrhagic EBV encephalitis with a fatal outcome, in an adult immunocompetent man.


Assuntos
Anticorpos Antivirais/sangue , Encéfalo/patologia , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/imunologia , Leucoencefalite Hemorrágica Aguda/etiologia , Adulto , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Encéfalo/virologia , DNA Viral/análise , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/patologia , Evolução Fatal , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Leucoencefalite Hemorrágica Aguda/patologia , Imageamento por Ressonância Magnética , Masculino , Reação em Cadeia da Polimerase
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