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1.
PLoS Med ; 19(2): e1003892, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35104279

RESUMO

BACKGROUND: Preterm birth is the leading cause of neonatal morbidity and mortality. The recurrence rate of spontaneous preterm birth is high, and additional preventive measures are required. Our objective was to assess the effectiveness of low-dose aspirin compared to placebo in the prevention of preterm birth in women with a previous spontaneous preterm birth. METHODS AND FINDINGS: We performed a parallel multicentre, randomised, double-blinded, placebo-controlled trial (the APRIL study). The study was performed in 8 tertiary and 26 secondary care hospitals in the Netherlands. We included women with a singleton pregnancy and a history of spontaneous preterm birth of a singleton between 22 and 37 weeks. Participants were randomly assigned to aspirin 80 mg daily or placebo initiated between 8 and 16 weeks of gestation and continued until 36 weeks or delivery. Randomisation was computer generated, with allocation concealment by using sequentially numbered medication containers. Participants, their healthcare providers, and researchers were blinded for treatment allocation. The primary outcome was preterm birth <37 weeks of gestation. Secondary outcomes included a composite of poor neonatal outcome (bronchopulmonary dysplasia, periventricular leukomalacia > grade 1, intraventricular hemorrhage > grade 2, necrotising enterocolitis > stage 1, retinopathy of prematurity, culture proven sepsis, or perinatal death). Analyses were performed by intention to treat. From May 31, 2016 to June 13, 2019, 406 women were randomised to aspirin (n = 204) or placebo (n = 202). A total of 387 women (81.1% of white ethnic origin, mean age 32.5 ± SD 3.8) were included in the final analysis: 194 women were allocated to aspirin and 193 to placebo. Preterm birth <37 weeks occurred in 41 (21.2%) women in the aspirin group and 49 (25.4%) in the placebo group (relative risk (RR) 0.83, 95% confidence interval (CI) 0.58 to 1.20, p = 0.32). In women with ≥80% medication adherence, preterm birth occurred in 24 (19.2%) versus 30 (24.8%) women (RR 0.77, 95% CI 0.48 to 1.25, p = 0.29). The rate of the composite of poor neonatal outcome was 4.6% (n = 9) versus 2.6% (n = 5) (RR 1.79, 95% CI 0.61 to 5.25, p = 0.29). Among all randomised women, serious adverse events occurred in 11 out of 204 (5.4%) women allocated to aspirin and 11 out of 202 (5.4%) women allocated to placebo. None of these serious adverse events was considered to be associated with treatment allocation. The main study limitation is the underpowered sample size due to the lower than expected preterm birth rates. CONCLUSIONS: In this study, we observed that low-dose aspirin did not significantly reduce the preterm birth rate in women with a previous spontaneous preterm birth. However, a modest reduction of preterm birth with aspirin cannot be ruled out. Further research is required to determine a possible beneficial effect of low-dose aspirin for women with a previous spontaneous preterm birth. TRIAL REGISTRATION: Dutch Trial Register (NL5553, NTR5675) https://www.trialregister.nl/trial/5553.


Assuntos
Aspirina/administração & dosagem , Trabalho de Parto Prematuro/prevenção & controle , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Países Baixos , Gravidez , Nascimento Prematuro/prevenção & controle
2.
Acta Obstet Gynecol Scand ; 100(8): 1419-1429, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33606270

RESUMO

INTRODUCTION: Little is known about the pathophysiology of hyperemesis gravidarum (HG). Proposed underlying causes are multifactorial and thyroid function is hypothesized to be causally involved. In this study, we aimed to assess the utility of thyroid-stimulating hormone (TSH) and free thyroxine (FT4) as a marker and predictor for the severity and clinical course of HG. MATERIAL AND METHODS: We conducted a prospective cohort study including women admitted for HG between 5 and 20 weeks of gestation in 19 hospitals in the Netherlands. Women with a medical history of thyroid disease were excluded. TSH and FT4 were measured at study entry. To adjust for gestational age, we calculated TSH multiples of the median (MoM). We assessed HG severity at study entry as severity of nausea and vomiting (by the Pregnancy Unique Quantification of Emesis and nausea score), weight change compared with prepregnancy weight, and quality of life. We assessed the clinical course of HG as severity of nausea and vomiting and quality of life 1 week after inclusion, duration of hospital admissions, and readmissions. We performed multivariable regression analysis with absolute TSH, TSH MoMs, and FT4. RESULTS: Between 2013 and 2016, 215 women participated in the cohort. TSH, TSH MoM, and FT4 were available for, respectively, 150, 126, and 106 of these women. Multivariable linear regression analysis showed that lower TSH MoM was significantly associated with increased weight loss or lower weight gain at study entry (ΔKg; ß = 2.00, 95% CI 0.47-3.53), whereas absolute TSH and FT4 were not. Lower TSH, not lower TSH MoM or FT4, was significantly associated with lower nausea and vomiting scores 1 week after inclusion (ß = 1.74, 95% CI 0.36-3.11). TSH and FT4 showed no association with any of the other markers of the severity or clinical course of HG. Twenty-one out of 215 (9.8%) women had gestational transient thyrotoxicosis. Women with gestational transient thyrotoxicosis had a lower quality of life 1 week after inclusion than women with no gestational transient thyrotoxicosis (p = 0.03). CONCLUSIONS: Our findings show an inconsistent role for TSH, TSH MoM, or FT4 at time of admission and provide little guidance on the severity and clinical course of HG.


Assuntos
Hiperêmese Gravídica/diagnóstico , Diagnóstico Pré-Natal , Tireotropina/sangue , Tiroxina/sangue , Adulto , Biomarcadores/sangue , Estudos de Coortes , Feminino , Humanos , Hiperêmese Gravídica/sangue , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos , Índice de Gravidade de Doença
3.
BMC Infect Dis ; 20(1): 450, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32591017

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) is a global cause of severe respiratory morbidity and mortality in infants. While preventive and therapeutic interventions are being developed, including antivirals, vaccines and monoclonal antibodies, little is known about the global molecular epidemiology of RSV. INFORM is a prospective, multicenter, global clinical study performed by ReSViNET to investigate the worldwide molecular diversity of RSV isolates collected from children less than 5 years of age. METHODS: The INFORM study is performed in 17 countries spanning all inhabited continents and will provide insight into the molecular epidemiology of circulating RSV strains worldwide. Sequencing of > 4000 RSV-positive respiratory samples is planned to detect temporal and geographical molecular patterns on a molecular level over five consecutive years. Additionally, RSV will be cultured from a subset of samples to study the functional implications of specific mutations in the viral genome including viral fitness and susceptibility to different monoclonal antibodies. DISCUSSION: The sequencing and functional results will be used to investigate susceptibility and resistance to novel RSV preventive or therapeutic interventions. Finally, a repository of globally collected RSV strains and a database of RSV sequences will be created.


Assuntos
Genoma Viral , Epidemiologia Molecular/métodos , Polimorfismo Genético , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vírus Sincicial Respiratório Humano/genética , Anticorpos Monoclonais/uso terapêutico , Antivirais/efeitos adversos , Antivirais/uso terapêutico , Pré-Escolar , Farmacorresistência Bacteriana/genética , Feminino , Genótipo , Humanos , Imunização Passiva , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , Vírus Sincicial Respiratório Humano/imunologia , Vírus Sincicial Respiratório Humano/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
4.
J Med Virol ; 91(12): 2117-2124, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31410862

RESUMO

Respiratory syncytial virus (RSV) causes significant mortality in hospitalized adults. Prediction of poor outcomes improves targeted management and clinical outcomes. We externally validated and updated existing models to predict poor outcome in hospitalized RSV-infected adults. In this single center, retrospective, observational cohort study, we included hospitalized adults with respiratory tract infections (RTIs) and a positive polymerase chain reaction for RSV (A/B) on respiratory tract samples (2005-2018). We validated existing prediction models and updated the best discriminating model by revision, recalibration, and incremental value testing. We included 192 RSV-infected patients (median age 60.7 years, 57% male, 65% immunocompromised, and 43% with lower RTI). Sixteen patients (8%) died within 30 days. During hospitalization, 16 (8%) died, 30 (16%) were admitted to intensive care unit, 21 (11%) needed invasive mechanical ventilation, and 5 (3%) noninvasive positive pressure ventilation. Existing models performed moderately at external validation, with C-statistics 0.6 to 0.7 and moderate calibration. Updating to a model including lower RTI, chronic pulmonary disease, temperature, confusion and urea, increased the C-statistic to 0.76 (95% confidence interval, 0.61-0.91) to predict in-hospital mortality. In conclusion, existing models to predict poor prognosis among hospitalized RSV-infected adults perform moderately at external validation. A prognostic model may help to identify and treat RSV-infected adults at high-risk of death.


Assuntos
Mortalidade Hospitalar , Hospitalização/estatística & dados numéricos , Modelos Estatísticos , Infecções por Vírus Respiratório Sincicial/mortalidade , Infecções Respiratórias/mortalidade , Idoso , Regras de Decisão Clínica , Feminino , Humanos , Hospedeiro Imunocomprometido , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Países Baixos , Prognóstico , Infecções por Vírus Respiratório Sincicial/diagnóstico , Infecções Respiratórias/virologia , Estudos Retrospectivos
5.
Eur J Pediatr ; 178(4): 455-462, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30637465

RESUMO

Severe respiratory syncytial virus (RSV) infection during infancy is associated with ongoing respiratory morbidity. In a large birth cohort of 2210 healthy preterm infants born at 32-35 weeks of gestation, we aimed to determine the role of atopy in the link between RSV hospitalization and current wheeze at age 6. We defined current wheeze as parent-reported wheeze or the use of respiratory medication in the past 12 months. Based on a positive family history of atopic disease, we distinguished between children with and without atopic predisposition. Six-year follow-up data was obtained in 997/1559 (64%) children of which 102 (10.2%) children had been hospitalized with RSV during infancy. Current wheeze was present in 184/997 (18.6%) children. RSV hospitalization was an independent risk factor for current wheeze in children without atopic predisposition (aOR 4.05 [95% CI 1.22-12.52]) but not in children with this atopic background (aOR 1.50 [95% CI 0.81-2.71]).Conclusion: This is the largest published birth cohort demonstrating that in late preterm infants, atopic predisposition defines the relationship between RSV hospitalization and current wheeze. Future RSV prevention trials aiming to prevent ongoing respiratory symptoms should be analyzed separately for atopic status. What is Known: • RSV infection is responsible for a significant burden of disease in young children worldwide. • Severe RSV infection in early life is associated with asthmatic symptoms later in life. What is New: • This is the largest published birth cohort reporting about the role of atopic predisposition in the link between severe RSV infection and current wheeze at school age. • We show that RSV hospitalization in infancy is an independent risk factor for current wheeze in late preterm children without atopic predisposition at age 6. This was not seen in children with atopic predisposition.


Assuntos
Hospitalização/estatística & dados numéricos , Sons Respiratórios/etiologia , Infecções por Vírus Respiratório Sincicial/epidemiologia , Índice de Gravidade de Doença , Asma/epidemiologia , Asma/etiologia , Asma/genética , Estudos de Casos e Controles , Criança , Feminino , Seguimentos , Predisposição Genética para Doença , Humanos , Hipersensibilidade Imediata/epidemiologia , Hipersensibilidade Imediata/genética , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Pais , Gravidez , Estudos Prospectivos , Sons Respiratórios/genética , Fatores de Risco , Inquéritos e Questionários
6.
Diabetes Obes Metab ; 20(8): 1894-1902, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29603547

RESUMO

AIM: Diabetes is associated with a high risk of adverse pregnancy outcomes. Optimal glycaemic control is fundamental and is traditionally monitored with self-measured glucose profiles and periodic HbA1c measurements. We investigated the effectiveness of additional use of retrospective continuous glucose monitoring (CGM) in diabetic pregnancies. MATERIAL AND METHODS: We performed a nationwide multicentre, open label, randomized, controlled trial to study pregnant women with type 1 or type 2 diabetes who were undergoing insulin therapy at gestational age < 16 weeks, or women who were undergoing insulin treatment for gestational diabetes at gestational age < 30 weeks. Women were randomly allocated (1:1) to intermittent use of retrospective CGM or to standard treatment. Glycaemic control was assessed by CGM for 5-7 days every 6 weeks in the CGM group, while self-monitoring of blood glucose and HbA1c measurements were applied in both groups. Primary outcome was macrosomia, defined as birth weight above the 90th percentile. Secondary outcomes were glycaemic control and maternal and neonatal complications. RESULTS: Between July 2011 and September 2015, we randomized 300 pregnant women with type 1 (n = 109), type 2 (n = 82) or with gestational (n = 109) diabetes to either CGM (n = 147) or standard treatment (n = 153). The incidence of macrosomia was 31.0% in the CGM group and 28.4% in the standard treatment group (relative risk [RR], 1.06; 95% CI, 0.83-1.37). HbA1c levels were similar between treatment groups. CONCLUSIONS: In diabetic pregnancy, use of intermittent retrospective CGM did not reduce the risk of macrosomia. CGM provides detailed information concerning glycaemic fluctuations but, as a treatment strategy, does not translate into improved pregnancy outcome.


Assuntos
Glicemia/análise , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 2/sangue , Diabetes Gestacional/sangue , Macrossomia Fetal/prevenção & controle , Monitorização Ambulatorial , Gravidez em Diabéticas/sangue , Adulto , Terapia Combinada , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/terapia , Diabetes Gestacional/fisiopatologia , Diabetes Gestacional/terapia , Feminino , Macrossomia Fetal/epidemiologia , Macrossomia Fetal/etiologia , Hemoglobinas Glicadas/análise , Humanos , Hiperglicemia/prevenção & controle , Hipoglicemia/prevenção & controle , Incidência , Recém-Nascido , Análise de Intenção de Tratamento , Perda de Seguimento , Masculino , Países Baixos/epidemiologia , Pacientes Desistentes do Tratamento , Gravidez , Gravidez em Diabéticas/fisiopatologia , Gravidez em Diabéticas/terapia , Risco
7.
Gynecol Oncol ; 146(3): 449-456, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28645428

RESUMO

OBJECTIVE: To evaluate the cost-effectiveness of a diagnostic laparoscopy prior to primary cytoreductive surgery to prevent futile primary cytoreductive surgery (i.e. leaving >1cm residual disease) in patients suspected of advanced stage ovarian cancer. METHODS: An economic analysis was conducted alongside a randomized controlled trial in which patients suspected of advanced stage ovarian cancer who qualified for primary cytoreductive surgery were randomized to either laparoscopy or primary cytoreductive surgery. Direct medical costs from a health care perspective over a 6-month time horizon were analyzed. Health outcomes were expressed in quality-adjusted life-years (QALYs) and utility was based on patient's response to the EQ-5D questionnaires. We primarily focused on direct medical costs based on Dutch standard prices. RESULTS: We studied 201 patients, of whom 102 were randomized to laparoscopy and 99 to primary cytoreductive surgery. No significant difference in QALYs (utility=0.01; 95% CI 0.006 to 0.02) was observed. Laparoscopy reduced the number of futile laparotomies from 39% to 10%, while its costs were € 1400 per intervention, making the overall costs of both strategies comparable (difference € -80 per patient (95% CI -470 to 300)). Findings were consistent across various sensitivity analyses. CONCLUSION: In patients with suspected advanced stage ovarian cancer, a diagnostic laparoscopy reduced the number of futile laparotomies, without increasing total direct medical health care costs, or adversely affecting complications or quality of life.


Assuntos
Procedimentos Cirúrgicos de Citorredução/economia , Custos de Cuidados de Saúde , Laparoscopia/economia , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/cirurgia , Quimioterapia Adjuvante/economia , Análise Custo-Benefício , Técnicas de Diagnóstico por Cirurgia/economia , Feminino , Humanos , Futilidade Médica , Pessoa de Meia-Idade , Terapia Neoadjuvante/economia , Estadiamento de Neoplasias , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida
8.
BMC Pregnancy Childbirth ; 17(1): 223, 2017 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-28705190

RESUMO

BACKGROUND: Preterm birth (birth before 37 weeks of gestation) is a major problem in obstetrics and affects an estimated 15 million pregnancies worldwide annually. A history of previous preterm birth is the strongest risk factor for preterm birth, and recurrent spontaneous preterm birth affects more than 2.5 million pregnancies each year. A recent meta-analysis showed possible benefits of the use of low dose aspirin in the prevention of recurrent spontaneous preterm birth. We will assess the (cost-)effectiveness of low dose aspirin in comparison with placebo in the prevention of recurrent spontaneous preterm birth in a randomized clinical trial. METHODS/DESIGN: Women with a singleton pregnancy and a history of spontaneous preterm birth in a singleton pregnancy (22-37 weeks of gestation) will be asked to participate in a multicenter, randomized, double blinded, placebo controlled trial. Women will be randomized to low dose aspirin (80 mg once daily) or placebo, initiated from 8 to 16 weeks up to maximal 36 weeks of gestation. The primary outcome measure will be preterm birth, defined as birth at a gestational age (GA) < 37 weeks. Secondary outcomes will be a composite of adverse neonatal outcome and maternal outcomes, including subgroups of prematurity, as well as intrauterine growth restriction (IUGR) and costs from a healthcare perspective. Preterm birth will be analyzed as a group, as well as separately for spontaneous or indicated onset. Analysis will be performed by intention to treat. In total, 406 pregnant women have to be randomized to show a reduction of 35% in preterm birth from 36 to 23%. If aspirin is effective in preventing preterm birth, we expect that there will be cost savings, because of the low costs of aspirin. To evaluate this, a cost-effectiveness analysis will be performed comparing preventive treatment with aspirin with placebo. DISCUSSION: This trial will provide evidence as to whether or not low dose aspirin is (cost-) effective in reducing recurrence of spontaneous preterm birth. TRIAL REGISTRATION: Clinical trial registration number of the Dutch Trial Register: NTR 5675 . EudraCT-registration number: 2015-003220-31.


Assuntos
Aspirina/administração & dosagem , Trabalho de Parto Prematuro/prevenção & controle , Inibidores da Agregação Plaquetária/administração & dosagem , Cuidado Pré-Natal/métodos , Prevenção Secundária/métodos , Adolescente , Adulto , Aspirina/economia , Análise Custo-Benefício , Método Duplo-Cego , Feminino , Idade Gestacional , Humanos , Trabalho de Parto Prematuro/economia , Inibidores da Agregação Plaquetária/economia , Gravidez , Resultado da Gravidez , Cuidado Pré-Natal/economia , Recidiva , Prevenção Secundária/economia , Resultado do Tratamento , Adulto Jovem
9.
BMC Pregnancy Childbirth ; 17(1): 284, 2017 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-28870155

RESUMO

BACKGROUND: Preterm birth is in quantity and in severity the most important topic in obstetric care in the developed world. Progestogens and cervical pessaries have been studied as potential preventive treatments with conflicting results. So far, no study has compared both treatments. METHODS/DESIGN: The Quadruple P study aims to compare the efficacy of vaginal progesterone and cervical pessary in the prevention of adverse perinatal outcome associated with preterm birth in asymptomatic women with a short cervix, in singleton and multiple pregnancies separately. It is a nationwide open-label multicentre randomized clinical trial (RCT) with a superiority design and will be accompanied by an economic analysis. Pregnant women undergoing the routine anomaly scan will be offered cervical length measurement between 18 and 22 weeks in a singleton and at 16-22 weeks in a multiple pregnancy. Women with a short cervix, defined as less than, or equal to 35 mm in a singleton and less than 38 mm in a multiple pregnancy, will be invited to participate in the study. Eligible women will be randomly allocated to receive either progesterone or a cervical pessary. Following randomization, the silicone cervical pessary will be placed during vaginal examination or 200 mg progesterone capsules will be daily self-administered vaginally. Both interventions will be continued until 36 weeks gestation or until delivery, whichever comes first. Primary outcome will be composite adverse perinatal outcome of perinatal mortality and perinatal morbidity including bronchopulmonary dysplasia, intraventricular haemorrhage grade III and IV, periventricular leukomalacia higher than grade I, necrotizing enterocolitis higher than stage I, Retinopathy of prematurity (ROP) or culture proven sepsis. These outcomes will be measured up until 10 weeks after the expected due date. Secondary outcomes will be, among others, time to delivery, preterm birth rate before 28, 32, 34 and 37 weeks, admission to neonatal intensive care unit, maternal morbidity, maternal admission days for threatened preterm labour and costs. DISCUSSION: This trial will provide evidence on whether vaginal progesterone or a cervical pessary is more effective in decreasing adverse perinatal outcome in both singletons and multiples. TRIAL REGISTRATION: Trial registration number: NTR 4414 . Date of registration January 29th 2014.


Assuntos
Colo do Útero/patologia , Pessários , Nascimento Prematuro/prevenção & controle , Progesterona/administração & dosagem , Progestinas/administração & dosagem , Doenças do Colo do Útero/complicações , Administração Intravaginal , Adolescente , Adulto , Medida do Comprimento Cervical , Protocolos Clínicos , Feminino , Humanos , Gravidez , Resultado da Gravidez , Nascimento Prematuro/etiologia , Resultado do Tratamento , Doenças do Colo do Útero/diagnóstico por imagem , Doenças do Colo do Útero/patologia , Adulto Jovem
10.
BMC Med Res Methodol ; 16: 6, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26772804

RESUMO

BACKGROUND: To describe approaches used in systematic reviews of diagnostic test accuracy studies for assessing variability in estimates of accuracy between studies and to provide guidance in this area. METHODS: Meta-analyses of diagnostic test accuracy studies published between May and September 2012 were systematically identified. Information on how the variability in results was investigated was extracted. RESULTS: Of the 53 meta-analyses included in the review, most (n=48; 91%) presented variability in diagnostic accuracy estimates visually either through forest plots or ROC plots and the majority (n=40; 75%) presented a test or statistical measure for the variability. Twenty-eight reviews (53%) tested for variability beyond chance using Cochran's Q test and 31 (58%) reviews quantified it with I(2). 7 reviews (13%) presented between-study variance estimates (τ(2)) from random effects models and 3 of these presented a prediction interval or ellipse to facilitate interpretation. Half of all the meta-analyses specified what was considered a significant amount of variability (n=24; 49%). CONCLUSIONS: Approaches to assessing variability in estimates of accuracy varied widely between diagnostic test accuracy reviews and there is room for improvement. We provide initial guidance, complemented by an overview of the currently available approaches.


Assuntos
Testes Diagnósticos de Rotina/estatística & dados numéricos , Testes Diagnósticos de Rotina/normas , Metanálise como Assunto , Literatura de Revisão como Assunto , Análise de Variância , Testes Diagnósticos de Rotina/métodos , Humanos , Publicações/normas , Publicações/estatística & dados numéricos , Curva ROC , Reprodutibilidade dos Testes
11.
Am J Epidemiol ; 179(4): 423-31, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24272278

RESUMO

Latent class models (LCMs) combine the results of multiple diagnostic tests through a statistical model to obtain estimates of disease prevalence and diagnostic test accuracy in situations where there is no single, accurate reference standard. We performed a systematic review of the methodology and reporting of LCMs in diagnostic accuracy studies. This review shows that the use of LCMs in such studies increased sharply in the past decade, notably in the domain of infectious diseases (overall contribution: 59%). The 64 reviewed studies used a range of differently specified parametric latent variable models, applying Bayesian and frequentist methods. The critical assumption underlying the majority of LCM applications (61%) is that the test observations must be independent within 2 classes. Because violations of this assumption can lead to biased estimates of accuracy and prevalence, performing and reporting checks of whether assumptions are met is essential. Unfortunately, our review shows that 28% of the included studies failed to report any information that enables verification of model assumptions or performance. Because of the lack of information on model fit and adequate evidence "external" to the LCMs, it is often difficult for readers to judge the validity of LCM-based inferences and conclusions reached.


Assuntos
Testes Diagnósticos de Rotina/estatística & dados numéricos , Modelos Estatísticos , Teorema de Bayes , Testes Diagnósticos de Rotina/normas , Padrões de Referência , Sensibilidade e Especificidade
12.
BMC Med Res Methodol ; 14: 33, 2014 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-24588874

RESUMO

BACKGROUND: Drawing conclusions from systematic reviews of test accuracy studies without considering the methodological quality (risk of bias) of included studies may lead to unwarranted optimism about the value of the test(s) under study. We sought to identify to what extent the results of quality assessment of included studies are incorporated in the conclusions of diagnostic accuracy reviews. METHODS: We searched MEDLINE and EMBASE for test accuracy reviews published between May and September 2012. We examined the abstracts and main texts of these reviews to see whether and how the results of quality assessment were linked to the accuracy estimates when drawing conclusions. RESULTS: We included 65 reviews of which 53 contained a meta-analysis. Sixty articles (92%) had formally assessed the methodological quality of included studies, most often using the original QUADAS tool (n = 44, 68%). Quality assessment was mentioned in 28 abstracts (43%); with a majority (n = 21) mentioning it in the methods section. In only 5 abstracts (8%) were results of quality assessment incorporated in the conclusions. Thirteen reviews (20%) presented results of quality assessment in the main text only, without further discussion. Forty-seven reviews (72%) discussed results of quality assessment; the most frequent form was as limitations in assessing quality (n = 28). Only 6 reviews (9%) further linked the results of quality assessment to their conclusions, 3 of which did not conduct a meta-analysis due to limitations in the quality of included studies. In the reviews with a meta-analysis, 19 (36%) incorporated quality in the analysis. Eight reported significant effects of quality on the pooled estimates; in none of them these effects were factored in the conclusions. CONCLUSION: While almost all recent diagnostic accuracy reviews evaluate the quality of included studies, very few consider results of quality assessment when drawing conclusions. The practice of reporting systematic reviews of test accuracy should improve if readers not only want to be informed about the limitations in the available evidence, but also on the associated implications for the performance of the evaluated tests.


Assuntos
Interpretação Estatística de Dados , Testes Diagnósticos de Rotina/estatística & dados numéricos , Garantia da Qualidade dos Cuidados de Saúde/métodos , Viés , Estudos Transversais , Erros de Diagnóstico , Humanos , Projetos de Pesquisa , Sensibilidade e Especificidade
13.
Ann Intern Med ; 159(3): 195-202, 2013 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-23922065

RESUMO

A universal challenge in studies that quantify the accuracy of diagnostic tests is establishing whether each participant has the disease of interest. Ideally, the same preferred reference standard would be used for all participants; however, for practical or ethical reasons, alternative reference standards that are often less accurate are frequently used instead. The use of different reference standards across participants in a single study is known as differential verification.Differential verification can cause severely biased accuracy estimates of the test or model being studied. Many variations of differential verification exist, but not all introduce the same risk of bias. A risk-of-bias assessment requires detailed information about which participants receive which reference standards and an estimate of the accuracy of the alternative reference standard. This article classifies types of differential verification and explores how they can lead to bias. It also provides guidance on how to report results and assess the risk of bias when differential verification occurs and highlights potential ways to correct for the bias.


Assuntos
Testes Diagnósticos de Rotina/normas , Viés , Humanos , Padrões de Referência , Medição de Risco
14.
PLoS Med ; 10(10): e1001531, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24143138

RESUMO

BACKGROUND: In diagnostic studies, a single and error-free test that can be used as the reference (gold) standard often does not exist. One solution is the use of panel diagnosis, i.e., a group of experts who assess the results from multiple tests to reach a final diagnosis in each patient. Although panel diagnosis, also known as consensus or expert diagnosis, is frequently used as the reference standard, guidance on preferred methodology is lacking. The aim of this study is to provide an overview of methods used in panel diagnoses and to provide initial guidance on the use and reporting of panel diagnosis as reference standard. METHODS AND FINDINGS: PubMed was systematically searched for diagnostic studies applying a panel diagnosis as reference standard published up to May 31, 2012. We included diagnostic studies in which the final diagnosis was made by two or more persons based on results from multiple tests. General study characteristics and details of panel methodology were extracted. Eighty-one studies were included, of which most reported on psychiatry (37%) and cardiovascular (21%) diseases. Data extraction was hampered by incomplete reporting; one or more pieces of critical information about panel reference standard methodology was missing in 83% of studies. In most studies (75%), the panel consisted of three or fewer members. Panel members were blinded to the results of the index test results in 31% of studies. Reproducibility of the decision process was assessed in 17 (21%) studies. Reported details on panel constitution, information for diagnosis and methods of decision making varied considerably between studies. CONCLUSIONS: Methods of panel diagnosis varied substantially across studies and many aspects of the procedure were either unclear or not reported. On the basis of our review, we identified areas for improvement and developed a checklist and flow chart for initial guidance for researchers conducting and reporting of studies involving panel diagnosis. Please see later in the article for the Editors' Summary.


Assuntos
Prova Pericial , Tomada de Decisões , Humanos , Editoração , Padrões de Referência
15.
J Healthc Qual ; 45(5): 261-271, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37428942

RESUMO

BACKGROUND: Low-value care is healthcare leading to no or little clinical benefit for the patient. The best (combinations of) interventions to reduce low-value care are unclear. PURPOSE: To provide an overview of randomized controlled trials (RCTs) evaluating deimplementation strategies, to quantify the effectiveness and describe different combinations of strategies. METHODS: Analysis of 121 RCTs (1990-2019) evaluating a strategy to reduce low-value care, identified by a systematic review. Deimplementation strategies were described and associations between strategy characteristics and effectiveness explored. RESULTS: Of 109 trials comparing deimplementation to usual care, 75 (69%) reported a significant reduction of low-value healthcare practices. Seventy-three trials included in a quantitative analysis showed a median relative reduction of 17% (IQR 7%-42%). The effectiveness of deimplementation strategies was not associated with the number and types of interventions applied. CONCLUSIONS AND IMPLICATIONS: Most deimplementation strategies achieved a considerable reduction of low-value care. We found no signs that a particular type or number of interventions works best for deimplementation. Future deimplementation studies should map relevant contextual factors, such as the workplace culture or economic factors. Interventions should be tailored to these factors and provide details regarding sustainability of the effect.


Assuntos
Cuidados de Baixo Valor , Local de Trabalho , Humanos , Condições de Trabalho , Revisões Sistemáticas como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
World J Diabetes ; 12(6): 868-882, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34168734

RESUMO

BACKGROUND: Implementation of new diagnostic criteria for gestational diabetes mellitus (GDM) are still a subject of debate, mostly due to concerns regarding the effects on the number of women diagnosed with GDM and the risk profile of the women newly diagnosed. AIM: To estimate the impact of the World Health Organization (WHO) 2013 criteria compared with the WHO 1999 criteria on the incidence of gestational diabetes mellitus as well as to determine the diagnostic accuracy for detecting adverse pregnancy outcomes. METHODS: We retrospectively analyzed a single center Dutch cohort of 3338 women undergoing a 75 g oral glucose tolerance test where the WHO 1999 criteria to diagnose GDM were clinically applied. Women were categorized into four groups: non-GDM by both criteria, GDM by WHO 1999 only (excluded from GDM), GDM by WHO 2013 only (newly diagnosed) and GDM by both criteria. We compared maternal characteristics, pregnancy outcomes and likelihood ratios for adverse pregnancy outcomes. RESULTS: Retrospectively applying the WHO 2013 criteria increased the cohort incidence by 13.1%, from 19.3% to 32.4%. Discordant diagnoses occurred in 21.3%; 4.1% would no longer be labelled as GDM, and 17.2% were newly diagnosed. Compared to the non-GDM group, women newly diagnosed were older, had higher rates of obesity, higher diastolic blood pressure and higher rates of caesarean deliveries. Their infants were more often delivered preterm, large-for-gestational-age and were at higher risk of a 5 min Apgar score < 7. Women excluded from GDM were older and had similar pregnancy outcomes compared to the non-GDM group, except for higher rates of shoulder dystocia (4.3% vs 1.3%, P = 0.015). Positive likelihood ratios for adverse outcomes in all groups were generally low, ranging from 0.54 to 2.95. CONCLUSION: Applying the WHO 2013 criteria would result in a substantial increase in GDM diagnoses. Newly diagnosed women are at increased risk for pregnancy adverse outcomes. This risk, however, seems to be lower than those identified by the WHO 1999 criteria. This could potentially influence the treatment effect that can be achieved in this group. Evidence on treatment effects in newly diagnosed women is urgently needed.

19.
Br J Gen Pract ; 70(701): e858-e865, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33199293

RESUMO

BACKGROUND: It is recognised that medical tests are overused in primary care; however, it is unclear how best to reduce their use. AIM: To identify which strategies are effective in reducing the use of low-value medical tests in primary care settings. DESIGN AND SETTING: Systematic review. METHOD: The databases MEDLINE, EMBASE, and Rx for Change were searched (January 1990 to November 2019) for randomised controlled trials (RCTs) that evaluated strategies to reduce the use of low-value medical tests in primary care settings. Two reviewers selected eligible RCTs, extracted data, and assessed their risk of bias. RESULTS: Of the 16 RCTs included in the review, 11 reported a statistically significant reduction in the use of low-value medical tests. The median of the differences between the relative reductions in the intervention and control arms was 17% (interquartile range 12% to 24%). Strategies using reminders or audit/feedback showed larger reduction than those without these components (22% versus 14%, and 22% versus 13%, respectively) and patient-targeted strategies showed larger reductions than those not targeted at patients (51% versus 17%). Very few studies investigated the sustainability of the effect, adverse events, cost-effectiveness, or patient-reported outcomes related to reducing the use of low-value tests. CONCLUSION: This review indicates that it is possible to reduce the use of low-value medical tests in primary care, especially by using multiple components including reminders, audit/feedback, and patient-targeted interventions. To implement these strategies widely in primary care settings, more research is needed not only to investigate their effectiveness, but also to examine adverse events, cost-effectiveness, and patient-reported outcomes.


Assuntos
Atenção Primária à Saúde , Humanos
20.
ERJ Open Res ; 6(4)2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33043055

RESUMO

BACKGROUND: Because diagnosing asthma in school-aged children is challenging, a variety of proxies for asthma are used in clinical practice and research settings as indicators of this disease. We aimed to provide insight into the agreement between various asthma indicators based on parental report, medical diagnosis and spirometry. METHODS: Children from the WHISTLER birth cohort performed spirometry and were followed up with parental ISAAC (International Study of Asthma and Allergies in Childhood) questionnaires about asthma at 5 and 8 years of age. Medical data were extracted from primary care records. We compared 15 asthma indicators based on parental report, medical diagnosis and spirometry using positive agreement, κ statistics and latent class cluster analysis. RESULTS: At 5 years of age, 1007 children completed a study visit, while 803 children visited at 8 years of age. Depending on the indicator, the responder and child's age, the asthma prevalence ranged from 0.2% to 26.6%. Cluster analysis revealed classes related to the presence of recent symptoms and a decreased lung function. Agreement between parents and doctors was generally low with κ coefficients ranging from 0.07 (recent wheeze) to 0.52 (recent asthma medication). Additionally, parental report showed to be sensitive to recall bias over time. CONCLUSIONS: Dependent on the asthma indicator, the responder and the age of the child, substantial differences in agreement were observed between commonly used indicators associated with asthmatic disease in school-aged children. Most agreement between parents and doctors was seen for objective and recent indicators such as the recent use of asthma medication. We advocate caution when literature with different asthma indicators is compared.

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