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1.
Blood Adv ; 7(5): 718-733, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35868022

RESUMO

Spatial heterogeneity is a common phenomenon in metastatic solid tumors and an evolving concept in multiple myeloma (MM). The interplay between malignant plasma cells (PCs) and the microenvironment has not yet been analyzed in MM. For this purpose, we performed bone marrow aspirates and imaging-guided biopsies of corresponding lesions in newly diagnosed MM (NDMM) and relapsed/refractory MM (RRMM) patients. PCs were isolated and subjected to whole-exome sequencing (WES). Non-PCs were studied with next-generation flow (NGF) and T-cell receptor sequencing (TCRseq) to analyze the connection between malignant and nonmalignant cells in the bone marrow and in lesions. Although we observed a strong overlap from WES, NGF, and TCRseq in patients with intramedullary disease, WES revealed significant spatial heterogeneity in patients with extramedullary disease. NGF showed significant immunosuppression in RRMM compared with NDMM as indicated by fewer myeloid dendritic cells, unswitched memory B cells, Th9 cells, and CD8 effector memory T cells but more natural killer and regulatory T cells. Additionally, fewer T-cell receptor (TCR) sequences were detected in RRMM compared with NDMM and healthy individuals. After induction therapy, TCR repertoire richness increased to levels of healthy individuals, and NGF showed more regulatory T cells and myeloid-derived suppressor cells, regardless of depth of response. Clinical significance of imaging-guided biopsies of lesions was demonstrated by detection of monoclonal PCs in patients without measurable residual disease (MRD) in aspirates from the iliac crest as well as identification of secondary primary malignancies in MRD- patients. Furthermore, site-specific clones with different drug susceptibilities and genetically defined high-risk features were detected by our workflow.


Assuntos
Mieloma Múltiplo , Neoplasias de Plasmócitos , Humanos , Mieloma Múltiplo/tratamento farmacológico , Medula Óssea/patologia , Plasmócitos/patologia , Microambiente Tumoral
2.
J Clin Virol ; 154: 105222, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35797940

RESUMO

BACKGROUND: Antigen testing has become an essential part of fighting the ongoing COVID-19 pandemic. With the continual increase in available tests, independent and extensive comparative evaluations using data from external quality assessment (EQA) studies to evaluate test performance between different users are required. OBJECTIVES: An EQA scheme was established to assess the sensitivity of antigen tests and the potential impact of circulating SARS-CoV-2 strains on their performance. STUDY DESIGN: Panels were prepared for three challenges in 2021 containing inactivated SARS-CoV-2-positive samples of various genetic strains (including variants of concern, VOCs) at different concentrations, and negative samples. Data was analysed based on qualitative testing results in relation to the antigen test used. RESULTS: Participants registered for each individual challenge in any combination. In total, 258 respondents from 27 countries worldwide were counted submitting 472 datasets. All core samples were correctly reported by 76.7 to 83.1% at participant level and by 73.5 to 83.8% at dataset level. Sensitivity differences could be shown in viral loads and SARS-CoV-2 strains/variants including the impact on performance by a B.1.1.7-like mutant strain with a deletion in the nucleoprotein gene. Lateral flow rapid antigen tests showed a higher rate of false negatives in general compared with automated point-of-care tests and laboratory ELISA/immunoassays. CONCLUSIONS: EQA schemes can provide valuable data to inform participants about weaknesses in their testing process or methods and support ongoing assay evaluations for regulatory approval or post-market surveillance.


Assuntos
COVID-19 , COVID-19/diagnóstico , Humanos , Pandemias , SARS-CoV-2/genética , Sensibilidade e Especificidade
3.
Euro Surveill ; 25(27)2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32672149

RESUMO

Laboratory preparedness with quality-assured diagnostic assays is essential for controlling the current coronavirus disease (COVID-19) outbreak. We conducted an external quality assessment study with inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) samples to support clinical laboratories with a proficiency testing option for molecular assays. To analyse SARS-CoV-2 testing performance, we used an online questionnaire developed for the European Union project RECOVER to assess molecular testing capacities in clinical diagnostic laboratories.


Assuntos
Técnicas de Laboratório Clínico/métodos , Técnicas de Laboratório Clínico/normas , Infecções por Coronavirus/diagnóstico , Coronavirus/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Pandemias , Pneumonia Viral/diagnóstico , Betacoronavirus , COVID-19 , Teste para COVID-19 , Vacinas contra COVID-19 , Serviços de Laboratório Clínico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Surtos de Doenças , Europa (Continente) , Humanos , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Reação em Cadeia da Polimerase em Tempo Real/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , SARS-CoV-2 , Sensibilidade e Especificidade , Inquéritos e Questionários
4.
Eur J Clin Microbiol Infect Dis ; 38(9): 1633-1641, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31140071

RESUMO

The quality of PCR to detect vancomycin-resistant enterococci (VRE) was evaluated by analysing their performance in six consecutive external quality assessment (EQA) schemes, organized annually since 2013 by Quality Control for Molecular Diagnostics. VRE EQA panels consisted of 12-14 heat-inactivated samples. Sensitivity was tested with vanA-positive Enterococcus faecium (E. faecium), vanB-positive E. faecium, E. faecalis or E. gallinarum or vanC-positive E. gallinarum in different concentrations. Vancomycin-susceptible enterococci, Staphylococcus aureus or sample matrix was used to study the specificity. Participants were asked to report the VRE resistance status of each sample. The detection rate of vanA-positive samples was already 95% in the 2013 EQA panel (range 94-97%) and remained stable over the years. The 2013 detection rate of vanB-positive samples was 82% but increased significantly by more than 10% in subsequent years (96% in 2014, 95% in 2015, 92% in 2016 and 93% in 2017/2018, p < 0.05). The vanC detection rate by the limited number of assays specifically targeting this gene was lower compared to vanA/B (range 55-89%). The number of false positives in the true-negative sample (8% in 2013 to 1.4% in 2018) as well as the van-gene-negative bacterial samples (4% in 2013 to 0% in 2018) declined over the years. In the six years of VRE proficiency testing to date, the detection of vanA-positive strains was excellent and an increased sensitivity in vanB detection as well as an increase in specificity was observed. Commercial and in-house assays performed equally well.


Assuntos
Patologia Molecular/estatística & dados numéricos , Patologia Molecular/normas , Reação em Cadeia da Polimerase/normas , Controle de Qualidade , Resistência a Vancomicina/genética , Enterococos Resistentes à Vancomicina/genética , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Carbono-Oxigênio Ligases/genética , Enterococcus faecium/genética , Infecções por Bactérias Gram-Positivas/microbiologia , Testes de Sensibilidade Microbiana , Sensibilidade e Especificidade , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/isolamento & purificação
5.
Cytometry B Clin Cytom ; 96(3): 201-208, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30565840

RESUMO

BACKGROUND: Minimal/measurable residual disease (MRD) testing by flow cytometry (FC) has been proposed as a potential surrogate clinical endpoint in plasma cell myeloma (PCM) clinical trials. As a result, effort has gone into standardizing this approach on PCM patients. AIMS: To assess inter-laboratory variation in FC MRD testing of PCM patients in an independent inter-laboratory study. METHODS: A dilution series of five stabilized bone marrow samples manufactured to contain 0%, 0.1%, 0.01%, 0.001%, and 0.0001% neoplastic plasma cells (PCs) were tested blind, using standardized FC PCM MRD assays by 10 international laboratories. RESULTS: Laboratories' assays broadly adhered to the consensus guidelines; however, some deviations were identified in panel design, fluorochrome conjugates, and lysis reagents. Despite this, all laboratories that returned results detected neoplastic PCs down to 0.001% of leucocytes. 6/8 laboratories detected neoplastic PCs at a level of 0.0001%. Quantitative data returned by laboratories showed good consensus and linearity with increasing variation at lower levels of MRD. However, examples of analytical and post analytical error were identified. SUMMARY/CONCLUSION: Broadly standardized PCM MRD FC assays can attain the lower limit of detection (LOD) required by current and future clinical trials, an important consideration in establishing PCM MRD testing as a surrogate clinical marker in PCM clinical trials. Laboratories' assays showed good linearity, encouraging the prediction of survival based on log reduction in neoplastic PC populations in future clinical trials. However, the deviations from consensus guidelines identified in this study would suggest that if PCM MRD assays are further standardized interlaboratory variation could be reduced. © 2018 International Clinical Cytometry Society.


Assuntos
Células da Medula Óssea/patologia , Citometria de Fluxo/normas , Ensaio de Proficiência Laboratorial , Mieloma Múltiplo/diagnóstico , Plasmócitos/patologia , Células da Medula Óssea/imunologia , Citometria de Fluxo/métodos , Humanos , Cooperação Internacional , Limite de Detecção , Contagem de Linfócitos , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Neoplasia Residual , Variações Dependentes do Observador , Plasmócitos/imunologia , Guias de Prática Clínica como Assunto , Prognóstico , Recidiva , Análise de Sobrevida
7.
Viruses ; 10(9)2018 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-30216988

RESUMO

Quality Control for Molecular Diagnostics (QCMD), an international provider for External Quality Assessment (EQA) programmes, has introduced a programme for molecular diagnostics of Zika virus (ZIKV) in 2016, which has been continuously offered to interested laboratories since that time. The EQA schemes provided from 2016 to 2018 revealed that 86.7% (92/106), 82.4% (89/108), and 88.2% (90/102) of the participating laboratories reported correct results for all samples, respectively in 2016, 2017, and 2018. The review of results indicated a need for improvement concerning analytical sensitivity and specificity of the test methods. Comparison with the outcomes of other EQA initiatives briefly summarized here show that continuous quality assurance is important to improve laboratory performance and to increase preparedness with reliable diagnostic assays for effective patient management, infection and outbreak control.


Assuntos
Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/normas , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/virologia , Zika virus/genética , Surtos de Doenças , História do Século XXI , Humanos , Garantia da Qualidade dos Cuidados de Saúde , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Infecção por Zika virus/história , Infecção por Zika virus/prevenção & controle
9.
BMJ Open ; 7(11): e014577, 2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29102983

RESUMO

OBJECTIVES: To evaluate the 12-month costs and quality-adjusted life years (QALYs) gained to the Italian National Health Service of facilitated access to a website for hazardous drinkers compared with a standard face-to-face brief intervention (BI). DESIGN: Randomised 1:1 non-inferiority trial. SETTING: Practices of 58 general practitioners (GPs) in Italy. PARTICIPANTS: Of 9080 patients (>18 years old) approached to take part in the trial, 4529 (49·9%) logged on to the website and 3841 (84.8%) undertook online screening for hazardous drinking. 822 (21.4%) screened positive and 763 (19.9%) were recruited to the trial. INTERVENTIONS: Patients were randomised to receive either a face-to-face BI or access via a brochure from their GP to an alcohol reduction website (facilitated access). PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome is the cost per QALY gained of facilitated access compared with face-to-face. A secondary analysis includes total costs and benefits per 100 patients, including number of hazardous drinkers prevented at 12 months. RESULTS: The average time required for the face-to-face BI was 8 min (95% CI 7.5 min to 8.6 min). Given the maximum time taken for facilitated access of 5 min, face-to-face is an additional 3 min: equivalent to having time for another GP appointment for every three patients referred to the website. Complete case analysis adjusting for baseline the difference in QALYs for facilitated access is 0.002 QALYs per patient (95% CI -0.007 to 0.011). CONCLUSIONS: Facilitated access to a website to reduce hazardous drinking costs less than a face-to-face BI given by a GP with no worse outcomes. The lower cost of facilitated access, particularly in regards to investment of time, may facilitate the increase in provision of BIs for hazardous drinking. TRIAL REGISTRATION NUMBER: NCT01638338;Post-results.


Assuntos
Consumo de Bebidas Alcoólicas/economia , Consumo de Bebidas Alcoólicas/terapia , Análise Custo-Benefício/estatística & dados numéricos , Internet , Comportamento de Redução do Risco , Adulto , Consumo de Bebidas Alcoólicas/psicologia , Feminino , Seguimentos , Humanos , Itália , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde/métodos , Qualidade de Vida
10.
IEEE Trans Biomed Eng ; 64(5): 1089-1098, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27416585

RESUMO

OBJECTIVE: Flow cytometry (FC) is a widely acknowledged technology in diagnosis of acute myeloid leukemia (AML) and has been indispensable in determining progression of the disease. Although FC plays a key role as a posttherapy prognosticator and evaluator of therapeutic efficacy, the manual analysis of cytometry data is a barrier to optimization of reproducibility and objectivity. This study investigates the utility of our recently introduced nonparametric Bayesian framework in accurately predicting the direction of change in disease progression in AML patients using FC data. METHODS: The highly flexible nonparametric Bayesian model based on the infinite mixture of infinite Gaussian mixtures is used for jointly modeling data from multiple FC samples to automatically identify functionally distinct cell populations and their local realizations. Phenotype vectors are obtained by characterizing each sample by the proportions of recovered cell populations, which are, in turn, used to predict the direction of change in disease progression for each patient. RESULTS: We used 200 diseased and nondiseased immunophenotypic panels for training and tested the system with 36 additional AML cases collected at multiple time points. The proposed framework identified the change in direction of disease progression with accuracies of 90% (nine out of ten) for relapsing cases and 100% (26 out of 26) for the remaining cases. CONCLUSIONS: We believe that these promising results are an important first step toward the development of automated predictive systems for disease monitoring and continuous response evaluation. SIGNIFICANCE: Automated measurement and monitoring of therapeutic response is critical not only for objective evaluation of disease status prognosis but also for timely assessment of treatment strategies.


Assuntos
Algoritmos , Biomarcadores Tumorais/metabolismo , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/metabolismo , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/metabolismo , Teorema de Bayes , Interpretação Estatística de Dados , Progressão da Doença , Citometria de Fluxo/métodos , Humanos , Leucemia Mieloide Aguda/patologia , Recidiva Local de Neoplasia/patologia , Reconhecimento Automatizado de Padrão/métodos , Recidiva , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Oncotarget ; 7(43): 69097-69110, 2016 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-27533245

RESUMO

BACKGROUND: Regulatory T (Treg) cells, a subset of CD4+ T lymphocytes, are mediators of immunosuppression in cancer, and, thus, variants in genes encoding Treg cell immune molecules could be associated with ovarian cancer. METHODS: In a population of 15,596 epithelial ovarian cancer (EOC) cases and 23,236 controls, we measured genetic associations of 1,351 SNPs in Treg cell pathway genes with odds of ovarian cancer and tested pathway and gene-level associations, overall and by histotype, for the 25 genes, using the admixture likelihood (AML) method. The most significant single SNP associations were tested for correlation with expression levels in 44 ovarian cancer patients. RESULTS: The most significant global associations for all genes in the pathway were seen in endometrioid ( p = 0.082) and clear cell ( p = 0.083), with the most significant gene level association seen with TGFBR2 ( p = 0.001) and clear cell EOC. Gene associations with histotypes at p < 0.05 included: IL12 ( p = 0.005 and p = 0.008, serous and high-grade serous, respectively), IL8RA ( p = 0.035, endometrioid and mucinous), LGALS1 ( p = 0.03, mucinous), STAT5B ( p = 0.022, clear cell), TGFBR1 ( p = 0.021 endometrioid) and TGFBR2 ( p = 0.017 and p = 0.025, endometrioid and mucinous, respectively). CONCLUSIONS: Common inherited gene variation in Treg cell pathways shows some evidence of germline genetic contribution to odds of EOC that varies by histologic subtype and may be associated with mRNA expression of immune-complex receptor in EOC patients.


Assuntos
Adenocarcinoma de Células Claras/genética , Predisposição Genética para Doença/genética , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Polimorfismo de Nucleotídeo Único , Proteínas Serina-Treonina Quinases/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Adenocarcinoma de Células Claras/imunologia , Adulto , Idoso , Carcinoma Epitelial do Ovário , Feminino , Regulação Neoplásica da Expressão Gênica , Frequência do Gene , Genótipo , Humanos , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/imunologia , Neoplasias Ovarianas/imunologia , Receptor do Fator de Crescimento Transformador beta Tipo II , Fatores de Risco , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo
12.
Blood ; 125(16): 2467-70, 2015 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-25746327

RESUMO

Major and ongoing changes in health care financing and delivery in the United States have altered opportunities and incentives for new physicians to specialize in nonmalignant hematology. At the same time, effective clinical tools and strategies continue to rapidly emerge. Consequently, there is an imperative to foster workforce innovation to ensure sustainable professional roles for hematologists, reliable patient access to optimal hematology expertise, and optimal patient outcomes. The American Society of Hematology is building a collection of case studies to guide the creation of institutionally supported systems-based clinical hematologist positions that predominantly focus on nonmalignant hematology. These roles offer a mix of guidance regarding patient management and the appropriate use and stewardship of clinical resources, as well as development of new testing procedures and protocols.


Assuntos
Atenção à Saúde/métodos , Hematologia/métodos , Oncologia/métodos , Papel do Médico , Atenção à Saúde/economia , Atenção à Saúde/tendências , Hematologia/economia , Hematologia/tendências , Humanos , Oncologia/economia , Oncologia/tendências , Estados Unidos
14.
Implement Sci ; 8: 11, 2013 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-23347874

RESUMO

BACKGROUND: The European level of alcohol consumption, and the subsequent burden of disease, is high compared to the rest of the world. While screening and brief interventions in primary healthcare are cost-effective, in most countries they have hardly been implemented in routine primary healthcare. In this study, we aim to examine the effectiveness and efficiency of three implementation interventions that have been chosen to address key barriers for improvement: training and support to address lack of knowledge and motivation in healthcare providers; financial reimbursement to compensate the time investment; and internet-based counselling to reduce workload for primary care providers. METHODS/DESIGN: In a cluster randomized factorial trial, data from Catalan, English, Netherlands, Polish, and Swedish primary healthcare units will be collected on screening and brief advice rates for hazardous and harmful alcohol consumption. The three implementation strategies will be provided separately and in combination in a total of seven intervention groups and compared with a treatment as usual control group. Screening and brief intervention activities will be measured at baseline, during 12 weeks and after six months. Process measures include health professionals' role security and therapeutic commitment of the participating providers (SAAPPQ questionnaire). A total of 120 primary healthcare units will be included, equally distributed over the five countries. Both intention to treat and per protocol analyses are planned to determine intervention effectiveness, using random coefficient regression modelling. DISCUSSION: Effective interventions to implement screening and brief interventions for hazardous alcohol use are urgently required. This international multi-centre trial will provide evidence to guide decision makers.


Assuntos
Alcoolismo/prevenção & controle , Aconselhamento/métodos , Internet , Adolescente , Adulto , Idoso , Análise por Conglomerados , Diagnóstico Precoce , Medicina Geral/economia , Medicina Geral/educação , Medicina Geral/normas , Humanos , Capacitação em Serviço/organização & administração , Pessoa de Meia-Idade , Motivação , Profissionais de Enfermagem/educação , Avaliação de Resultados em Cuidados de Saúde , Assistentes Médicos/educação , Encaminhamento e Consulta , Mecanismo de Reembolso , Tamanho da Amostra , Adulto Jovem
15.
J Clin Virol ; 52(3): 257-60, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21893429

RESUMO

BACKGROUND: WNV epidemics occur worldwide, new WNV isolates were isolated in southern-east Europe belonging to WNV lineage 2. A first international proficiency study on WNV indicted that some laboratories were not able to detect WNV lineage 2 virus genome by their PCR diagnostic assays. Therefore an actual External Quality Assessment with both virus lineages was performed to monitor the improvements in molecular diagnostics. OBJECTIVES: To asses the proficiency of laboratories to detect West Nile virus with molecular diagnostic tests. STUDY DESIGN: A test panel of different WNV isolates and virus dilutions was given to 26 laboratories to test the samples with their routine diagnostic methods. RESULTS: Twenty-one participating laboratories provided 28 data set results. WNV lineage 1 was detected with high overall efficiency of 92% (67.9-100%) but two different WNV lineage 2 strains were detected at lower rates (mean = 73%, 67.9-75%) by the different PCR assays. 93% of the laboratories were able to detect a WNV lineage 1 with a concentration of 1.2×10(4)copies/ml but the detection rate was decreased to 68% for 1.2×10(3)copies/ml. One laboratory generated false-positive result from the non-virus control samples and 29% of the datasets showed false-positive results for non-WNV flavivirus samples. CONCLUSIONS: The WNV EQA showed an improved proficiency of laboratories as compared to the first EQA. However, the data suggest that problems in the detection of both lineages were still present since the first proficiency test was performed in 2006. Further proceedings versus the detection of both lineages are needed particularly for in-house assays.


Assuntos
Ensaio de Proficiência Laboratorial , Técnicas de Diagnóstico Molecular/métodos , Febre do Nilo Ocidental/diagnóstico , Vírus do Nilo Ocidental/isolamento & purificação , Erros de Diagnóstico , Humanos , Laboratórios/normas , Patologia Molecular , Controle de Qualidade , Sensibilidade e Especificidade , Febre do Nilo Ocidental/epidemiologia , Vírus do Nilo Ocidental/genética
16.
PLoS One ; 6(3): e14740, 2011 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-21408060

RESUMO

BACKGROUND: Interventions delivered via the Internet have the potential to address the problem of hazardous alcohol consumption at minimal incremental cost, with potentially major public health implications. It was hypothesised that providing access to a psychologically enhanced website would result in greater reductions in drinking and related problems than giving access to a typical alcohol website simply providing information on potential harms of alcohol. DYD-RCT Trial registration: ISRCTN 31070347. METHODOLOGY/PRINCIPAL FINDINGS: A two-arm randomised controlled trial was conducted entirely on-line through the Down Your Drink (DYD) website. A total of 7935 individuals who screened positive for hazardous alcohol consumption were recruited and randomized. At entry to the trial, the geometric mean reported past week alcohol consumption was 46.0 (SD 31.2) units. Consumption levels reduced substantially in both groups at the principal 3 month assessment point to an average of 26.0 (SD 22.3) units. Similar changes were reported at 1 month and 12 months. There were no significant differences between the groups for either alcohol consumption at 3 months (intervention: control ratio of geometric means 1.03, 95% CI 0.97 to 1.10) or for this outcome and the main secondary outcomes at any of the assessments. The results were not materially changed following imputation of missing values, nor was there any evidence that the impact of the intervention varied with baseline measures or level of exposure to the intervention. CONCLUSIONS/SIGNIFICANCE: Findings did not provide support for the hypothesis that access to a psychologically enhanced website confers additional benefit over standard practice and indicate the need for further research to optimise the effectiveness of Internet-based behavioural interventions. The trial demonstrates a widespread and potentially sustainable demand for Internet based interventions for people with hazardous alcohol consumption, which could be delivered internationally. TRIAL REGISTRATION: Controlled-Trials.com ISRCTN31070347.


Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Consumo de Bebidas Alcoólicas/terapia , Internet , Consumo de Bebidas Alcoólicas/economia , Seguimentos , Humanos , Seleção de Pacientes , Resultado do Tratamento
17.
J Med Internet Res ; 13(1): e26, 2011 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-21371988

RESUMO

BACKGROUND: Attrition from follow-up is a major methodological challenge in randomized trials. Incentives are known to improve response rates in cross-sectional postal and online surveys, yet few studies have investigated whether they can reduce attrition from follow-up in online trials, which are particularly vulnerable to low follow-up rates. OBJECTIVES: Our objective was to determine the impact of incentives on follow-up rates in an online trial. METHODS: Two randomized controlled trials were embedded in a large online trial of a Web-based intervention to reduce alcohol consumption (the Down Your Drink randomized controlled trial, DYD-RCT). Participants were those in the DYD pilot trial eligible for 3-month follow-up (study 1) and those eligible for 12-month follow-up in the DYD main trial (study 2). Participants in both studies were randomly allocated to receive an offer of an incentive or to receive no offer of an incentive. In study 1, participants in the incentive arm were randomly offered a £5 Amazon.co.uk gift voucher, a £5 charity donation to Cancer Research UK, or entry in a prize draw for £250. In study 2, participants in the incentive arm were offered a £10 Amazon.co.uk gift voucher. The primary outcome was the proportion of participants who completed follow-up questionnaires in the incentive arm(s) compared with the no incentive arm. RESULTS: In study 1 (n = 1226), there was no significant difference in response rates between those participants offered an incentive (175/615, 29%) and those with no offer (162/611, 27%) (difference = 2%, 95% confidence interval [CI] -3% to 7%). There was no significant difference in response rates among the three different incentives offered. In study 2 (n = 2591), response rates were 9% higher in the group offered an incentive (476/1296, 37%) than in the group not offered an incentive (364/1295, 28%) (difference = 9%, 95% CI 5% to 12%, P < .001). The incremental cost per extra successful follow-up in the incentive arm was £110 in study 1 and £52 in study 2. CONCLUSION: Whereas an offer of a £10 Amazon.co.uk gift voucher can increase follow-up rates in online trials, an offer of a lower incentive may not. The marginal costs involved require careful consideration. TRIAL REGISTRATION: ISRCTN31070347; http://www.controlled-trials.com/ISRCTN31070347 (Archived by WebCite at http://www.webcitation.org/5wgr5pl3s).


Assuntos
Consumo de Bebidas Alcoólicas , Custos e Análise de Custo , Internet , Motivação , Adulto , Correio Eletrônico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Fatores de Tempo
18.
BMC Res Notes ; 3: 172, 2010 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-20565866

RESUMO

BACKGROUND: The practical and methodological challenges inherent in online behaviour change studies are both novel and complex. We relate our experiences of estimating and managing information technology (IT) research and intervention costs in an ongoing internet trial in the hope that others will find this information useful. FINDINGS: Actual IT costs were approximately twice those that had been originally estimated by external contractors. These original estimates for IT costs allowed little scope for the identification of new needs, which was intrinsic to the iterative nature of the research enterprise. CONCLUSIONS: Making greater provision for the uncertain nature of these costs in future studies is a key practical lesson for the planning of future online behaviour change studies.

19.
BMC Med Res Methodol ; 10: 38, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20433728

RESUMO

BACKGROUND: Trials frequently encounter difficulties in recruitment, but evidence on effective recruitment methods in primary care is sparse. A robust test of recruitment methods involves comparing alternative methods using a randomized trial, 'nested' in an ongoing 'host' trial. There are potential scientific, logistical and ethical obstacles to such studies. METHODS: Telephone interviews were undertaken with four groups of stakeholders (funders, principal investigators, trial managers and ethics committee chairs) to explore their views on the practicality and acceptability of undertaking nested trials of recruitment methods. These semi-structured interviews were transcribed and analysed thematically. RESULTS: Twenty people were interviewed. Respondents were familiar with recruitment difficulties in primary care and recognised the case for 'nested' studies to build an evidence base on effective recruitment strategies. However, enthusiasm for this global aim was tempered by the challenges of implementation. Challenges for host studies included increasing complexity and management burden; compatibility between the host and nested study; and the impact of the nested study on trial design and relationships with collaborators. For nested recruitment studies, there were concerns that host study investigators might have strong preferences, limiting the nested study investigators' control over their research, and also concerns about sample size which might limit statistical power. Nested studies needed to be compatible with the main trial and should be planned from the outset. Good communication and adequate resources were seen as important. CONCLUSIONS: Although research on recruitment was welcomed in principle, the issue of which study had control of key decisions emerged as critical. To address this concern, it appeared important to align the interests of both host and nested studies and to reduce the burden of hosting a recruitment trial. These findings should prove useful in devising a programme of research involving nested studies of recruitment interventions.


Assuntos
Ensaios Clínicos como Assunto/métodos , Seleção de Pacientes , Atenção Primária à Saúde , Projetos de Pesquisa , Pesquisadores , Ensaios Clínicos como Assunto/ética , Pesquisa sobre Serviços de Saúde , Humanos , Entrevistas como Assunto , Seleção de Pacientes/ética , Apoio à Pesquisa como Assunto
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