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A randomized, double-blind, placebo-controlled clinical trial was conducted to investigate the efficacy of infliximab, abatacept, and cenicriviroc in treating patients hospitalized with COVID-19. The patient's clinical status was assessed daily on an 8-point ordinal scale. We evaluated the totality of evidence on the efficacy of the 3 immunomodulators by considering all possible changes in the clinical status of each patient over time. We demonstrated that infliximab accelerated improvement and reduced deterioration of clinical status when added to standard of care. There was also evidence for the benefit of abatacept. There was no evidence for the benefit of cenicriviroc.
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Abatacepte , Tratamento Farmacológico da COVID-19 , COVID-19 , Infliximab , SARS-CoV-2 , Humanos , Abatacepte/uso terapêutico , Infliximab/uso terapêutico , Método Duplo-Cego , Masculino , Pessoa de Meia-Idade , Feminino , Resultado do Tratamento , Idoso , Hospitalização , Adulto , Agentes de Imunomodulação/uso terapêuticoRESUMO
Asthma is a heterogeneous disease, with multiple underlying inflammatory pathways and structural airway abnormalities that impact disease persistence and severity. Recent progress has been made in developing targeted asthma therapeutics, especially for subjects with eosinophilic asthma. However, there is an unmet need for new approaches to treat patients with severe and exacerbation-prone asthma, who contribute disproportionately to disease burden. Extensive deep phenotyping has revealed the heterogeneous nature of severe asthma and identified distinct disease subtypes. A current challenge in the field is to translate new and emerging knowledge about different pathobiologic mechanisms in asthma into patient-specific therapies, with the ultimate goal of modifying the natural history of disease. Here, we describe the Precision Interventions for Severe and/or Exacerbation-Prone Asthma (PrecISE) Network, a groundbreaking collaborative effort of asthma researchers and biostatisticians from around the United States. The PrecISE Network was designed to conduct phase II/proof-of-concept clinical trials of precision interventions in the population with severe asthma, and is supported by the National Heart, Lung, and Blood Institute of the National Institutes of Health. Using an innovative adaptive platform trial design, the PrecISE Network will evaluate up to 6 interventions simultaneously in biomarker-defined subgroups of subjects. We review the development and organizational structure of the PrecISE Network, and choice of interventions being studied. We hope that the PrecISE Network will enhance our understanding of asthma subtypes and accelerate the development of therapeutics for severe asthma.
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Asma/tratamento farmacológico , Medicina de Precisão , Comitês Consultivos , Asma/diagnóstico , Biomarcadores , Protocolos Clínicos , Ensaios Clínicos Fase II como Assunto , Humanos , Projetos de Pesquisa , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios XRESUMO
Acute respiratory distress syndrome (ARDS) is a heterogeneous clinical syndrome. Understanding of the complex pathways involved in lung injury pathogenesis, resolution, and repair has grown considerably in recent decades. Nevertheless, to date, only therapies targeting ventilation-induced lung injury have consistently proven beneficial, and despite these gains, ARDS morbidity and mortality remain high. Many candidate therapies with promise in preclinical studies have been ineffective in human trials, probably at least in part due to clinical and biological heterogeneity that modifies treatment responsiveness in human ARDS. A precision medicine approach to ARDS seeks to better account for this heterogeneity by matching therapies to subgroups of patients that are anticipated to be most likely to benefit, which initially might be identified in part by assessing for heterogeneity of treatment effect in clinical trials. In October 2019, the US National Heart, Lung, and Blood Institute convened a workshop of multidisciplinary experts to explore research opportunities and challenges for accelerating precision medicine in ARDS. Topics of discussion included the rationale and challenges for a precision medicine approach in ARDS, the roles of preclinical ARDS models in precision medicine, essential features of cohort studies to advance precision medicine, and novel approaches to clinical trials to support development and validation of a precision medicine strategy. In this Position Paper, we summarise workshop discussions, recommendations, and unresolved questions for advancing precision medicine in ARDS. Although the workshop took place before the COVID-19 pandemic began, the pandemic has highlighted the urgent need for precision therapies for ARDS as the global scientific community grapples with many of the key concepts, innovations, and challenges discussed at this workshop.
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Medicina de Precisão , Síndrome do Desconforto Respiratório , COVID-19 , Humanos , Síndrome do Desconforto Respiratório/terapiaRESUMO
Severe asthma accounts for almost half the cost associated with asthma. Severe asthma is driven by heterogeneous molecular mechanisms. Conventional clinical trial design often lacks the power and efficiency to target subgroups with specific pathobiological mechanisms. Furthermore, the validation and approval of new asthma therapies is a lengthy process. A large proportion of that time is taken by clinical trials to validate asthma interventions. The National Institutes of Health Precision Medicine in Severe and/or Exacerbation Prone Asthma (PrecISE) program was established with the goal of designing and executing a trial that uses adaptive design techniques to rapidly evaluate novel interventions in biomarker-defined subgroups of severe asthma, while seeking to refine these biomarker subgroups, and to identify early markers of response to therapy. The novel trial design is an adaptive platform trial conducted under a single master protocol that incorporates precision medicine components. Furthermore, it includes innovative applications of futility analysis, cross-over design with use of shared placebo groups, and early futility analysis to permit more rapid identification of effective interventions. The development and rationale behind the study design are described. The interventions chosen for the initial investigation and the criteria used to identify these interventions are enumerated. The biomarker-based adaptive design and analytic scheme are detailed as well as special considerations involved in the final trial design.
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Asma , Biomarcadores , Medicina de Precisão , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Projetos de PesquisaRESUMO
The Precision Interventions for Severe and/or Exacerbation-prone Asthma (PrecISE) study is an adaptive platform trial designed to investigate novel interventions to severe asthma. The study is conducted under a master protocol and utilizes a crossover design with each participant receiving up to five interventions and at least one placebo. Treatment assignments are based on the patients' biomarker profiles and precision health methods are incorporated into the interim and final analyses. We describe key elements of the PrecISE study including the multistage adaptive enrichment strategy, early stopping of an intervention for futility, power calculations, and the primary analysis strategy.
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Asma , Asma/diagnóstico , Asma/tratamento farmacológico , Biomarcadores , Humanos , Projetos de PesquisaRESUMO
The issuance of a report in 2010 by the National Research Council (NRC) of the National Academy of Sciences entitled 'The Prevention and Treatment of Missing Data in Clinical Trials,' commissioned by the US Food and Drug Administration, had an immediate impact on the way that statisticians and clinical researchers in both industry and regulatory agencies think about the missing data problem. We believe that there is currently great potential to improve study quality and interpretability-by reducing the amount of missing data through changes in trial design and conduct and by planning and conducting analyses that better account for the missing information. Here, we describe our view on some of the recommendations in the report and suggest ways in which these recommendations can be incorporated into new or ongoing clinical trials in order to improve their chance of success. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
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Ensaios Clínicos como Assunto , Confiabilidade dos Dados , United States Food and Drug Administration , Humanos , Estados UnidosRESUMO
PURPOSE: To describe prevalence and relationships to cardiovascular morbidity of depression, anxiety, and medication use among Hispanic/Latinos of different ethnic backgrounds. METHODS: Cross-sectional analysis of 15,864 men and women aged 18 to 74 years in the population-based Hispanic Community Health Study/Study of Latinos. Depressive and anxiety symptoms were assessed with shortened Center for Epidemiological Studies Depression Scale and Spielberger Trait Anxiety Scale. RESULTS: Prevalence of high depressive symptoms ranged from low of 22.3% (95% confidence interval [CI], 20.4-24.3) to high of 38.0% (95% CI, 35.2-41.0) among those of Mexican or Puerto Rican background, respectively. Adjusted odds ratios for depression rose monotonically with number of cardiovascular disease (CVD) risk factor from 1.46 (95% CI, 1.18-1.75) for those with one risk factors to 4.36 (95% CI, 2.47-7.70) for those with five risk factors. Antidepressant medication was used by 5% with striking differences between those with and without history of CVD (15.4% and 4.6%, respectively) and between insured (8.2%) and uninsured (1.8%). CONCLUSIONS: Among US Hispanics/Latinos, high depression and anxiety symptoms varied nearly twofold by Hispanic background and sex, history of CVD, and increasing number of CVD risk factors. Antidepressant medication use was lower than in the general population, suggesting under treatment especially among those who had no health insurance.
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Antidepressivos/administração & dosagem , Ansiedade/etnologia , Doenças Cardiovasculares/etnologia , Depressão/etnologia , Hispânico ou Latino , Adolescente , Adulto , Idoso , Estudos Transversais , Uso de Medicamentos , Emigrantes e Imigrantes/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Distribuição por Sexo , Estados Unidos/epidemiologia , Adulto JovemRESUMO
OBJECTIVE: We examine differences in prevalence of diabetes and rates of awareness and control among adults from diverse Hispanic/Latino backgrounds in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL). RESEARCH DESIGN AND METHODS: The HCHS/SOL, a prospective, multicenter, population-based study, enrolled from four U.S. metropolitan areas from 2008 to 2011 16,415 18-74-year-old people of Hispanic/Latino descent. Diabetes was defined by either fasting plasma glucose, impaired glucose tolerance 2 h after a glucose load, glycosylated hemoglobin (A1C), or documented use of hypoglycemic agents (scanned medications). RESULTS: Diabetes prevalence varied from 10.2% in South Americans and 13.4% in Cubans to 17.7% in Central Americans, 18.0% in Dominicans and Puerto Ricans, and 18.3% in Mexicans (P < 0.0001). Prevalence related positively to age (P < 0.0001), BMI (P < 0.0001), and years living in the U.S. (P = 0.0010) but was negatively related to education (P = 0.0005) and household income (P = 0.0043). Rate of diabetes awareness was 58.7%, adequate glycemic control (A1C <7%, 53 mmol/mol) was 48.0%, and having health insurance among those with diabetes was 52.4%. CONCLUSIONS: Present findings indicate a high prevalence of diabetes but considerable diversity as a function of Hispanic background. The low rates of diabetes awareness, diabetes control, and health insurance in conjunction with the negative associations between diabetes prevalence and both household income and education among Hispanics/Latinos in the U.S. have important implications for public health policies.
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Diabetes Mellitus/etnologia , Hispânico ou Latino/estatística & dados numéricos , Adolescente , Adulto , Idoso , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Masculino , Americanos Mexicanos/estatística & dados numéricos , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Características de Residência/estatística & dados numéricos , Fatores de Risco , Fatores Socioeconômicos , Estados Unidos/epidemiologia , Adulto JovemRESUMO
BACKGROUND: The prevention and control of hypertension is an essential component for reducing the burden of cardiovascular diseases. Here we describe the prevalence of hypertension in diverse Hispanic/Latino background groups and describe the proportion who are aware of their diagnosis, receiving treatment, and having their hypertension under control. METHODS: The Hispanic Community Health Study/Study of Latinos is a longitudinal cohort study of 16,415 Hispanics/Latinos, aged 18-74 years from 4 US communities (Bronx, NY; Chicago, IL; Miami, FL; and San Diego, CA). At baseline (2008-2011) the study collected extensive measurements and completed questionnaires related to research on cardiovascular diseases. Hypertension was defined as measured blood pressure ≥140/90mm Hg or use of antihypertensive medication. RESULTS: The total age-adjusted prevalence of hypertension in this study was 25.5% as compared with 27.4% in non-Hispanic whites in the National Health and Nutrition Examination Survey. Prevalence of hypertension increased with increasing age groups and was highest in Cuban, Puerto Rican, and Dominican background groups. The percent with hypertension who were aware, being treated with medication, or had their hypertension controlled was lower compared with US non-Hispanic whites with hypertension and it was lowest in those without health insurance. CONCLUSIONS: These findings indicate a significant deficit in treatment and control of hypertension among Hispanics/Latinos residing in the United States, particularly those without health insurance. Given the relative ease of identification of hypertension and the availability of low-cost medications, enabling better access to diagnostic and treatment services should reduce the burden of hypertension in Hispanic populations.
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Conscientização , Pressão Sanguínea/efeitos dos fármacos , Comportamentos Relacionados com a Saúde/etnologia , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Hispânico ou Latino/psicologia , Hipertensão/tratamento farmacológico , Hipertensão/etnologia , Hipoglicemiantes/uso terapêutico , Adolescente , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Hipertensão/diagnóstico , Masculino , Pessoas sem Cobertura de Seguro de Saúde/etnologia , Pessoa de Meia-Idade , Prevalência , Inquéritos e Questionários , Resultado do Tratamento , Estados Unidos/epidemiologia , Adulto JovemRESUMO
In the absence of placebo-controlled trials, determining the non-inferiority (NI) margin for comparing an experimental treatment with an active comparator is based on carefully selected well-controlled historical clinical trials. With this approach, information on the effect of the active comparator from other sources including observational studies and early phase trials is usually ignored because of the need to maintain active comparator effect across trials. This may lead to conservative estimates of the margin that translate into larger sample-size requirements for the design and subsequent frequentist analysis, longer trial durations, and higher drug development costs. In this article, we provide methodological approaches to determine NI margins that can utilize all relevant historical data through a novel power adjusted Bayesian meta-analysis, with Dirichlet process priors, that puts ordered weights on the amount of information a set of data contributes. We also provide a Bayesian decision rule for the non-inferiority analysis that is based on a broader use of available prior information and a sample-size determination that is based on this Bayesian decision rule. Finally, the methodology is illustrated through several examples.
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Anti-Infecciosos/uso terapêutico , Teorema de Bayes , Ensaios Clínicos como Assunto , Projetos de Pesquisa , Humanos , Metanálise como Assunto , Tamanho da AmostraRESUMO
Subpopulations and Intermediate Outcomes in COPD Study (SPIROMICS) is a multicentre observational study of chronic obstructive pulmonary disease (COPD) designed to guide future development of therapies for COPD by providing robust criteria for subclassifying COPD participants into groups most likely to benefit from a given therapy during a clinical trial, and identifying biomarkers/phenotypes that can be used as intermediate outcomes to reliably predict clinical benefit during therapeutic trials. The goal is to enrol 3200 participants in four strata. Participants undergo a baseline visit and three annual follow-up examinations, with quarterly telephone calls. Adjudication of exacerbations and mortality will be undertaken.
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Biomarcadores/metabolismo , Gerenciamento Clínico , Doença Pulmonar Obstrutiva Crônica/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Doença Pulmonar Obstrutiva Crônica/metabolismo , Espirometria , Inquéritos e Questionários , Tomografia Computadorizada por Raios XRESUMO
The number of statistical challenges facing regulators remains high, as does the importance of statistical thinking in the regulatory decision-making process. Statisticians in the Office of Biostatistics at the US Food and Drug Administration review hundreds of new drug and therapeutic biologic applications each year and advise sponsors on protocols numbering in the thousands. In addition to remaining up to date on the newest statistical methods, statisticians are often called upon for innovative approaches to difficult regulatory problems. This article presents the author's view of the important role that statisticians play in regulatory decision making, beginning with a broad overview of current office initiatives, including the development of guidance documents and a recent push for open and transparent collaboration with industry on methods development. Several recent examples are provided to illustrate the impact that statisticians can have on regulatory decisions through the use of strategic quantitative thinking. Also discussed are areas where it is believed that innovative statistical solutions or greater clarity on existing approaches is still needed.
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RATIONALE: Several studies suggest that nasal nitric oxide (nNO) measurement could be a test for primary ciliary dyskinesia (PCD), but the procedure and interpretation have not been standardized. OBJECTIVES: To use a standard protocol for measuring nNO to establish a disease-specific cutoff value at one site, and then validate at six other sites. METHODS: At the lead site, nNO was prospectively measured in individuals later confirmed to have PCD by ciliary ultrastructural defects (n = 143) or DNAH11 mutations (n = 6); and in 78 healthy and 146 disease control subjects, including individuals with asthma (n = 37), cystic fibrosis (n = 77), and chronic obstructive pulmonary disease (n = 32). A disease-specific cutoff value was determined, using generalized estimating equations (GEEs). Six other sites prospectively measured nNO in 155 consecutive individuals enrolled for evaluation for possible PCD. MEASUREMENTS AND MAIN RESULTS: At the lead site, nNO values in PCD (mean ± standard deviation, 20.7 ± 24.1 nl/min; range, 1.5-207.3 nl/min) only rarely overlapped with the nNO values of healthy control subjects (304.6 ± 118.8; 125.5-867.0 nl/min), asthma (267.8 ± 103.2; 125.0-589.7 nl/min), or chronic obstructive pulmonary disease (223.7 ± 87.1; 109.7-449.1 nl/min); however, there was overlap with cystic fibrosis (134.0 ± 73.5; 15.6-386.1 nl/min). The disease-specific nNO cutoff value was defined at 77 nl/minute (sensitivity, 0.98; specificity, >0.999). At six other sites, this cutoff identified 70 of the 71 (98.6%) participants with confirmed PCD. CONCLUSIONS: Using a standardized protocol in multicenter studies, nNO measurement accurately identifies individuals with PCD, and supports its usefulness as a test to support the clinical diagnosis of PCD.
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Síndrome de Kartagener/diagnóstico , Óxido Nítrico/análise , Adolescente , Adulto , Idoso , Asma/diagnóstico , Dineínas do Axonema/genética , Testes Respiratórios/métodos , Estudos de Casos e Controles , Criança , Pré-Escolar , Cílios/ultraestrutura , Fibrose Cística/diagnóstico , Feminino , Humanos , Síndrome de Kartagener/genética , Síndrome de Kartagener/patologia , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Mucosa Nasal/citologia , Mucosa Nasal/ultraestrutura , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Valores de Referência , Sensibilidade e Especificidade , Adulto JovemRESUMO
OBJECTIVE: To add to the evidence on comparative long-term effects of insulin analog glargine versus human NPH insulin on the risk for cancer. RESEARCH DESIGN AND METHODS: We identified cohorts of initiators of glargine and human NPH without an insulin prescription during the prior 19 months among patients covered by the Inovalon Medical Outcomes Research for Effectiveness and Economics Registry (MORE2 Registry) between January 2003 and December 2010. Patients were required to have a second prescription of the same insulin within 180 days and to be free of cancer. We balanced cohorts on risk factors for cancer outcomes based on comorbidities, comedication, and health care use during the prior 12 months using inverse probability of treatment weighting. Incident cancer was defined as having two claims for cancer (any cancer) or the same cancer (breast, prostate, colon) within 2 months. We estimated adjusted hazard ratios (HRs) and their 95% CI using weighted Cox models censoring for stopping, switching, or augmenting insulin treatment, end of enrollment, and mortality. RESULTS: More patients initiated glargine (43,306) than NPH (9,147). Initiators of glargine (NPH) were followed for 1.2 (1.1) years and 50,548 (10,011) person-years; 993 (178) developed cancer. The overall HR was 1.12 (95% CI 0.95-1.32). Results were consistent for breast cancer, prostate cancer, and colon cancer; various durations of treatment; and sensitivity analyses. CONCLUSIONS: Patients initiating insulin glargine rather than NPH do not seem to be at an increased risk for cancer. While our study contributes significantly to our evidence base for long-term effects, this evidence is very limited mainly based on actual dynamics in insulin prescribing.
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Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina Isófana/uso terapêutico , Insulina de Ação Prolongada/uso terapêutico , Insulina Regular Humana/uso terapêutico , Neoplasias/epidemiologia , Adulto , Idoso , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Incidência , Insulina Glargina , Insulina Isófana Humana , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Probabilidade , Modelos de Riscos Proporcionais , Sistema de Registros , Fatores de RiscoRESUMO
We develop a simple statistic for comparing rates of rare adverse events between treatment groups in postmarketing safety studies where the events have uncertain status. In this setting, the statistic is asymptotically equivalent to the logrank statistic, but the limiting distribution has Poisson and binomial components instead of being Gaussian. We develop two new procedures for computing critical values: a Gaussian approximation and a parametric bootstrap. Both numerical and asymptotic properties of the procedures are studied. The test procedures are demonstrated on a postmarketing safety study of the RotaTeq vaccine. This vaccine was developed to reduce the incidence of severe diarrhea in infants.
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Qualidade de Produtos para o Consumidor , Prontuários Médicos/estatística & dados numéricos , Modelos Estatísticos , Vigilância de Produtos Comercializados/métodos , Vigilância de Produtos Comercializados/estatística & dados numéricos , Incerteza , Humanos , Vacinas contra Rotavirus/normas , Vacinas Atenuadas/normasRESUMO
We develop a simple statistic for comparing rates of rare adverse events between treatment groups in postmarketing safety studies where the events have uncertain status. In this setting, the statistic is asymptotically equivalent to the logrank statistic, but the limiting distribution has Poisson and binomial components instead of being Gaussian. We develop two new procedures for computing critical values, a Gaussian approximation and a parametric bootstrap. Both numerical and asymptotic properties of the procedures are studied. The test procedures are demonstrated on a postmarketing safety study of the RotaTeq vaccine. This vaccine was developed to reduce the incidence of severe diarrhea in infants.
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Prontuários Médicos/normas , Segurança do Paciente/normas , Vigilância de Produtos Comercializados/métodos , Vigilância de Produtos Comercializados/normas , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Vacinas contra Rotavirus/efeitos adversos , Humanos , Lactente , Intussuscepção/etiologia , Intussuscepção/prevenção & controle , Prontuários Médicos/estatística & dados numéricos , Distribuição Normal , Segurança do Paciente/estatística & dados numéricos , Vigilância de Produtos Comercializados/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Vacinas Atenuadas/efeitos adversosRESUMO
BACKGROUND: In response to the Agency for Healthcare Research and Quality statement questioning the usefulness of "screening spirometry," the National Heart, Lung, and Blood Institute and the COPD Foundation held a consensus conference in June 2008 to establish a procedure to detect cases of COPD in the general population. Conference participants developed a three-stage approach, using a brief questionnaire, peak flow measurement with a pocket spirometer, and diagnostic quality spirometry. The overall objective of this study was to examine the usefulness of a simple questionnaire and peak flow measurement in screening for COPD in a self-selected population. We hypothesized that this combination would efficiently screen for clinically relevant COPD. METHODS: We queried individuals attending public events regarding the presence of wheeze and/or asthma, mucus production, dyspnea, exposure to irritants, and tobacco use. Peak expiratory flow (PEF) was then measured with a pocket spirometer. If PEF was < 70% predicted, spirometry was performed. In order to estimate the false-negative rate, a random sample of every 10th participant was also selected for spirometry. RESULTS: Between June 2008 and December 2009, 5,761 adults completed the risk assessment questionnaire. The mean age of the respondents was 54 years, 58% were women, and 88% were white. Of these, 5,638 participants completed pocket spirometry, and 315 (5.6%) had PEF < 70% predicted. Of 5,323 with normal PEF, 651 underwent spirometry. The performance of PEF was assessed via positive and negative predictive values relative to a diagnosis of clinically significant airflow obstruction, defined as FEV(1)/FEV(6) < the lower limit of normal and FEV(1) < 60% predicted. Of 4,238 subjects with at least two risk factors, 267 (6.3%) had PEF < 70%, compared with 48 of the 1,400 subjects (3.4%) with fewer than two risk factors (P < .001). Based on 729 participants with acceptable spirometry, 63.1% (113 of 179) of those with abnormal PEF tested positive for clinically significant airflow obstruction, compared with 5.5% (30 of 550) with normal PEF (P < .001). The estimated prevalence of significant COPD among the 5,638 screened was 8.7%, and sensitivity and specificity were 40.7% and 97.7%, respectively. CONCLUSIONS: A staged approach to COPD screening in adults is useful for detecting clinically significant airflow obstruction in our study population.