1,144 results match your criteria Controlled Clinical Trials[Journal]


On the generation and ownership of alpha in medical studies.

Authors:
Vance W Berger

Control Clin Trials 2004 Dec;25(6):613-9

National Cancer Institute, University of Maryland Baltimore County, Biometry Research Group, Executive Plaza North, Suite 3131, 6130 Executive Boulevard, MSC 7354, Bethesda, MD 20892-7354, USA.

Much is known about how to split alpha between or among several comparisons, or how to preserve the nominal alpha level with an exact analysis, but the issue of how alpha is generated, or where it comes from, has not received a commensurate degree of attention. It would seem that there is little point in working out methods to allocate or conserve alpha if it is unlimited in supply. Moreover, there seems to be a logical inconsistency in requiring that a given amount of alpha, generally 0. Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560400073
Publisher Site
http://dx.doi.org/10.1016/j.cct.2004.07.006DOI Listing
December 2004
7 Reads

An analysis of the effect of funding source in randomized clinical trials of second generation antipsychotics for the treatment of schizophrenia.

Control Clin Trials 2004 Dec;25(6):598-612

Department of Psychiatry and Human Behavior, University of Mississippi Medical Center, Jackson, MS, USA.

Objective: The effect of funding source on the outcome of randomized controlled trials has been investigated in several medical disciplines; however, psychiatry has been largely excluded from such analyses. In this article, randomized controlled trials of second generation antipsychotics in schizophrenia are reviewed and analyzed with respect to funding source (industry vs. non-industry funding). Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560400087
Publisher Site
http://dx.doi.org/10.1016/j.cct.2004.09.002DOI Listing
December 2004
6 Reads

Symptom recording in a randomised clinical trial: paper diaries vs. electronic or telephone data capture.

Control Clin Trials 2004 Dec;25(6):585-97

Department of Gastroenterology, Odense University Hospital, Odense, Denmark.

Background: Patients may be asked to register a symptom daily in clinical trials. A problem associated with this kind of registration is that patients do not always fill in the diary at the appropriate time. As there is evidence showing that memory is unreliable, this undermines the entire purpose of collecting daily data on paper diaries. Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560400086
Publisher Site
http://dx.doi.org/10.1016/j.cct.2004.09.001DOI Listing
December 2004
13 Reads

Statistical comparison of random allocation methods in cancer clinical trials.

Control Clin Trials 2004 Dec;25(6):572-84

Department of INdustrial Management and Engineering, Faculty of Engineering, Tokyo University of Science, Tokyo, Japan.

The selection of a trial design is an important issue in the planning of clinical trials. One of the most important considerations in trial design is the method of treatment allocation and appropriate analysis plan corresponding to the design. In this article, we conducted computer simulations using the actual data from 2158 rectal cancer patients enrolled in the surgery-alone group from seven randomized controlled trials in Japan to compare the performance of allocation methods, simple randomization, stratified randomization and minimization in relatively small-scale trials (total number of two groups are 50, 100, 150 or 200 patients). Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.08.004DOI Listing
December 2004
7 Reads

Analyzing bronchodilation with emphasis on disease type, age and sex.

Control Clin Trials 2004 Dec;25(6):563-71

Cardialysis B.V., Westblaak 92, 3012 KM Rotterdam, The Netherlands.

In the literature, different statistical methods to evaluate bronchodilator studies are used. These approaches are all based on the absence of residual heterogeneity and on baseline independency of the parameter under analysis. A database containing the lung function values of newly referred patients was used to assess these assumptions as function of the underlying diagnosis (asthma, bronchitis and emphysema) and to chart the characteristics of analysis of covariance, which (partly) deals with these drawbacks. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.08.006DOI Listing
December 2004
6 Reads

Geographic variability in patient characteristics, treatment and outcome in an International Trial of Magnesium in acute myocardial infarction.

Control Clin Trials 2004 Dec;25(6):553-62

The Clinical Trials Group, National Heart, Lung, and Blood Institute, 6701 Rockledge Drive, MSC 7936, Bethesda, MD 20892, USA.

Background: The interpretation of clinical trials and efforts directed at reducing the worldwide burden of coronary disease must take regional differences into account. This study examined the regional differences in baseline characteristics, treatment, and outcome in patients presenting with ST elevation myocardial infarction (STEMI) who were entered into the Magnesium in Coronaries (MAGIC) trial.

Methods And Results: MAGIC randomized 6213 patients to standard care with either placebo infusion or infusion of intravenous magnesium sulphate. Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560400089
Publisher Site
http://dx.doi.org/10.1016/j.cct.2004.08.005DOI Listing
December 2004
7 Reads

Measuring treatment impact: a review of patient-reported outcomes and other efficacy endpoints in approved product labels.

Control Clin Trials 2004 Dec;25(6):535-52

Pfizer Inc., Bridgewater, NJ 08807, USA.

Context: The term "patient-reported outcomes" (PROs) has evolved to include any endpoint derived from patient reports, whether collected in the clinic, in a diary, or by other means, including single-item outcome measures, event logs, symptom reports, formal instruments to measure health-related quality of life (HRQL), health status, adherence, and satisfaction with treatment. This term coincides with the explicit interest from drug development researchers and regulatory authorities in the appropriate utilization and reporting of treatment impact measures.

Objective: To determine the level and nature of use of PROs compared to other types of effectiveness endpoints in approved product labeling for new drugs recently approved in the United States. Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560400091
Publisher Site
http://dx.doi.org/10.1016/j.cct.2004.09.003DOI Listing
December 2004
11 Reads

Negative results in cancer clinical trials--equivalence or poor accrual?

Control Clin Trials 2004 Oct;25(5):525-33

University of Colorado Health Science Center, Room L18-8122, 12801 E 17th Avenue, Aurora, CO 80010, USA.

This study was performed to evaluate randomized cancer trials resulting negative regarding inadequate accrual, unsupported assumptions of equivalence and factors implied in such assumptions. A search in PubMed electronic data base was done for a sample of 800 most recently entered studies by March 2003 indexed with MESH term "neoplasms" and categorized according to design, intervention, outcome and conclusion. Minimal detectable differences with optimized power were calculated in each comparison according to number of patients accrued. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.08.001DOI Listing
October 2004
5 Reads

Ensuring the comparability of comparison groups: is randomization enough?

Control Clin Trials 2004 Oct;25(5):515-24

National Cancer Institute, EPN, Suite 3131, 6130 Executive Boulevard, MSC-7354, Bethesda, MD 20892-7354, USA.

Background: It is widely believed that baseline imbalances in randomized trials must necessarily be random. In fact, there is a type of selection bias that can cause substantial, systematic and reproducible baseline imbalances of prognostic covariates even in properly randomized trials. It is possible, given complete data, to quantify both the susceptibility of a given trial to this type of selection bias and the extent to which selection bias appears to have caused either observable or unobservable baseline imbalances. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.04.001DOI Listing
October 2004
6 Reads

Improving asthma symptom control in rural communities: the design of the Better Respiratory Education and Asthma Treatment in Hinton and Edson study.

Control Clin Trials 2004 Oct;25(5):502-14

Department of Public Health Sciences, University of Alberta, Edmonton, Alberta T6G 2C8, Canada.

Methods: The prevalence of asthma in adults in the United States is approximately 7%, and 9% of asthma patients will require hospitalization each year. Many patients do not seek care, as they do not recognize overuse of beta-agonists as a risk factor for poorly controlled asthma. However, pharmacists are able to identify these patients through refill information on reliever medication prescriptions and potentially initiate community-management opportunities for these patients. Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560400067
Publisher Site
http://dx.doi.org/10.1016/j.cct.2004.07.004DOI Listing
October 2004
7 Reads

The utility of partial cross-over designs in early phase randomized prevention trials.

Control Clin Trials 2004 Oct;25(5):493-501

University at Buffalo, Department of Biostatistics, Farber Hall Room 249A, 3435 Main St., Buffalo, NY 14214-3000, USA.

In this note, we outline the benefits of a partial cross-over design for a class of experiments where the interest is the cumulative effect of dose versus placebo. The goal of our design strategy is to answer several complex question efficiently in a phase II setting with a minimal number of assumptions with an eye towards planning a phase III study. Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560400069
Publisher Site
http://dx.doi.org/10.1016/j.cct.2004.07.005DOI Listing
October 2004
6 Reads

Evolution of the HALT-C Trial: pegylated interferon as maintenance therapy for chronic hepatitis C in previous interferon nonresponders.

Control Clin Trials 2004 Oct;25(5):472-92

The Hepatitis C Antiviral Long-term Treatment against Cirrhosis (HALT-C) Trial was designed to determine whether maintenance interferon therapy could slow disease progression in patients who had failed to eradicate hepatitis C virus (HCV) during prior interferon treatment (nonresponders). Ten clinical sites, a virological testing center, and a data coordinating center (DCC) were selected to collaborate in the design and implementation of the final protocol. Eligible patients had been treated previously with interferon for at least 12 weeks, with or without another antiviral, ribavirin, but still had persistent viremia. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.08.003DOI Listing
October 2004
11 Reads

SEARCH for Diabetes in Youth: a multicenter study of the prevalence, incidence and classification of diabetes mellitus in youth.

Authors:

Control Clin Trials 2004 Oct;25(5):458-71

SEARCH for Diabetes in Youth is an observational, multicenter study focusing on physician-diagnosed diabetes in individuals <20 years old. The study will estimate the population prevalence and incidence of diabetes by type, age, gender, and ethnicity and develop practical approaches to diabetes classification in 5 million children ( approximately 6% of the <20 U.S. Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560400070
Publisher Site
http://dx.doi.org/10.1016/j.cct.2004.08.002DOI Listing
October 2004
22 Reads

Challenges and innovations in enhancing adherence.

Control Clin Trials 2004 Oct;25(5):447-57

Department of Health and Exercise Science, PO Box 7868, Wake Forest University, Winston-Salem, NC 27109, USA.

Adherence is a complex phenomenon involving interactions among the individual, the environment and the community. In an adherence workshop, a small group of investigators discussed their experiences with challenges and innovations regarding adherence gleaned from clinical research. This article summarizes the information and outcomes of that meeting. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.07.003DOI Listing
October 2004
9 Reads

Validating electronic source data in clinical trials.

Authors:
Ronald G Marks

Control Clin Trials 2004 Oct;25(5):437-46

Department of Biostatistics, College of Medicine, University of Florida, P.O. Box 100212, Gainesville, FL 32610-0212, USA.

The clinical trials industry relies heavily on paper-based source documents as the foundation for the collection of its clinical research data from human subjects and medical records. This focus on paper documents has been prevalent throughout the history of clinical trials conduct, even as computing solutions advanced throughout the past 20 years. With the advent of additional electronic capabilities recently with the growth of Internet-based products to enhance business operations in many fields, the clinical trials industry remains uniquely behind most other industries in electronic technology adoptions. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.07.001DOI Listing
October 2004
5 Reads

Application of stochastic processes to participant recruitment in clinical trials.

Control Clin Trials 2004 Oct;25(5):429-36

Department of Biometry and Epidemiology, Medical University of South Carolina, 135 Cannon Street, Ste 303, P.O. Box 250835, Charleston, SC 29425, USA.

The allocation of sufficient time for participant recruitment is one of the fundamental aspects in planning a clinical trial. This paper illustrates how a Poisson process can be used to determine an optimal period of time for participant recruitment by simulating Poisson arrival into a clinical trial. The simulation study provides the means to generate of an empirical probability density function for the recruitment time based on time-dependent changes in the accrual rate. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.07.002DOI Listing
October 2004
5 Reads

Incorporating the sampling variation of the disease prevalence when calculating the sample size in a study to determine the diagnostic accuracy of a test.

Control Clin Trials 2004 Aug;25(4):417-27

Department of Biostatistics, Princess Margaret Hospital, University Health Network, 610 University Avenue, Toronto, ON, Canada M5G 2M9.

During the design stage of a study to assess the population sensitivity (P(S)) (or specificity) of a diagnostic test, the number of subjects (N) who will be administered both a gold standard test and a new test needs to be calculated. A common approach is to calculate the number of cases (n) with a specific disease or condition as diagnosed by the gold standard test first, and then to determine N based on the prevalence or incidence rate of the disease (P(P)) in the population, calculated as N=n/P(P). Due to sampling variation, given the sample size N, the number of cases having the disease identified by the gold standard test could be less than N x P(P). Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.06.003DOI Listing
August 2004
5 Reads

Adjustment for baseline measurement error in randomized controlled trials induces bias.

Control Clin Trials 2004 Aug;25(4):408-16

Screening and Test Evaluation Program (STEP), School of Public Health, The University of Sydney, Edward Ford Building, A27, Sydney, NSW 2006, Australia.

When estimating the treatment effect in a randomized controlled trial, it is common to have a continuous outcome which is also observed at baseline. These observations are often prone to measurement error, for example due to within-patient variability. Controversy exists in the literature about whether baseline measurement error should be adjusted for in this context. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.06.001DOI Listing
August 2004
4 Reads

Surveillance of the eye and vision in a clinical trial of MART1-transformed dendritic cells for metastatic melanoma.

Control Clin Trials 2004 Aug;25(4):400-7

Department of Ophthalmology, and the Jules Stein Eye Institute, and the UCLA Jonsson Comprehensive Cancer Center, University of California at Los Angeles, 100 Stein Plaza, Los Angeles, CA 90095-7000, USA.

Purpose: To report the protocol for surveillance of the eye and vision in a clinical trial of MART1-transduced dendritic cells for metastatic melanoma.

Methods: In a phase I/II clinical trial of dendritic cell-based genetic immunotherapy for metastatic cutaneous melanoma, ophthalmic evaluation is performed prior to immunization (Baseline Evaluation), 56+/-7 days after first vaccination (mid-study evaluation), when dendritic cell injections are complete 112+/-7 days after first vaccination (end-study evaluation) and 168+/-7 days after first vaccination (post-study evaluation).

Results: The protocol for baseline, mid-study and end-study evaluations of the eye and vision includes ophthalmic history, comprehensive ophthalmic examination, psychophysical and electrophysiological visual function assessment, fundus photography and fluorescein angiography. Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560400046
Publisher Site
http://dx.doi.org/10.1016/j.cct.2004.06.002DOI Listing
August 2004
10 Reads

When free condoms and spermicide are not enough: barriers and solutions to participant recruitment to community-based trials.

Control Clin Trials 2004 Aug;25(4):388-99

Department of Primary Care, University of Liverpool, Whelan Building, Quadrangle, Brownlow Hill, Liverpool L69 3GB, UK.

While randomised controlled trials remain the accepted 'gold standard' in medical research, participant recruitment is often problematic, particularly with primary care trials or those requiring healthy volunteers. Such difficulties can jeopardise the trial, leading to early abandonment, reduced statistical power or timetable and budget overruns. Substantial changes in recruitment plans may reduce the generalisability of the research. Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560400048
Publisher Site
http://dx.doi.org/10.1016/j.cct.2004.06.004DOI Listing
August 2004
7 Reads

Enrollment in clinical trials according to patients race: experience from the VA Cooperative Studies Program (1975-2000).

Control Clin Trials 2004 Aug;25(4):378-87

Center for Health Services Research in Primary Care, VA Medical Center, Durham, NC 27705, USA.

Background: Racial distribution of clinical trial participants is important because results from these studies serve to define evidence-based practice. This report summarizes the experience of the VA Cooperative Studies Program (CSP) in enrolling white, black and Hispanic patients.

Methods: An analysis of enrollment in randomized controlled trials conducted by VA CSP between 1975 and 2000. Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560400044
Publisher Site
http://dx.doi.org/10.1016/j.cct.2004.05.001DOI Listing
August 2004
14 Reads

Investigator and site selection and performing GCP clinical studies in India.

Authors:
Krishan Maggon

Control Clin Trials 2004 Aug;25(4):366-77

Pharma Biotech R&D, P.O. Box 1887, ICC-20 Route de Pré Bois, 1215, Geneva 15, Switzerland.

The optimum site and investigator selection process remains a closely guarded confidential matter and an essential part of development expertise of big pharmaceutical companies and CROs. The right and careful selection and evaluation of investigators and site is critical for successful completion of the trial within budget, timelines and generation of high quality data. The criteria for site and investigator selection in India for Good Clinical Practices (GCP) clinical trials are described for a start up company/CRO and can be applied to any country in Asia and Africa. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.06.006DOI Listing
August 2004
4 Reads

Issues in the design of a clinical trial with a behavioral intervention--the Zambia exclusive breast-feeding study.

Control Clin Trials 2004 Aug;25(4):353-65

Center for International Health and Development, Boston University School of Public Health, 710 Albany Street, 715, Boston, MA 02118, USA.

Purpose: We present the rationale and design of the Zambian Exclusive Breast-feeding Study (ZEBS), a randomized trial evaluating the efficacy of short-duration exclusive breast-feeding (EBF) as a strategy to reduce postnatal human immunodeficiency virus (HIV) transmission while preserving the other health benefits of this important mode of infant feeding.

Methods: One thousand two hundred HIV-positive pregnant women were recruited in Lusaka, Zambia, and followed with their infants for 24 months. In addition to Nevirapine (NVP), all women received intensive and frequent clinic- and home-based counseling to support exclusive breast-feeding. Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560400049
Publisher Site
http://dx.doi.org/10.1016/j.cct.2004.06.005DOI Listing
August 2004
11 Reads

Special populations recruitment for the Women's Health Initiative: successes and limitations.

Control Clin Trials 2004 Aug;25(4):335-52

Division of Preventive Medicine, University of Alabama at Birmingham, 1530 3rd Avenue South, MT 618, Birmingham, AL 35294-4410, USA.

The Women's Health Initiative (WHI) is a study designed to examine the major causes of death and disability in women. This multi-arm, randomized, controlled trial of over 160,000 post-menopausal women of varying ethnic and socioeconomic backgrounds and a goal of 20% of the study participants from minority populations is perhaps one of the most challenging recruitment efforts ever undertaken. Of the two main study arms, the Clinical Trial (CT) and the Observational Study (OS), the CT arm recruitment goal was to randomize 64,500 postmenopausal women 50-79 years of age. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.03.005DOI Listing
August 2004
20 Reads

Samples of exact k-stage group sequential designs for Phase II and Pilot studies.

Control Clin Trials 2004 Jun;25(3):326-33

Biostatistics, Department of Biostatistics, University of Florida, Gainesville, FL 32601-3330, USA.

That the test of H(0): p=p(0) versus H(1): p>p(0) can be based on a binomially distributed random variable is widely known among users of statistical methods. What is not generally known is that under certain very general conditions, it is possible to find an exact k-stage group sequential test whose total sample size is bounded above by the sample size for the single stage binomial test. That is, it is possible to find k-stage tests for detecting H(1) for which the sum of the sample sizes at each of the stages is bounded above by the sample size for the standard binomial test. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.03.004DOI Listing
June 2004
5 Reads
2 Citations

Multicenter trial of early treatment for retinopathy of prematurity: study design.

Control Clin Trials 2004 Jun;25(3):311-25

The Early Treatment for Retinopathy of Prematurity (ETROP) study was a randomized, prospective multicenter trial comparing the safety and efficacy of earlier vs. conventionally timed ablation of the peripheral retina for the management of moderate to severe retinopathy of prematurity (ROP). Approximately 7000 infants with birth weights <1251 g were screened at 26 centers over a 2-year period to achieve the sample size of 401 consented infants for the randomized trial. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.03.003DOI Listing
June 2004
5 Reads

The Prevention of Early Asthma in Kids study: design, rationale and methods for the Childhood Asthma Research and Education network.

Control Clin Trials 2004 Jun;25(3):286-310

Division of Pediatric Pulmonary Medicine, Arizona Respiratory Center, University of Arizona, 1501 N Campbell Avenue, PO Box 245073, Tucson, AZ 85724, USA.

Pediatric asthma remains an important public health concern as its prevalence and cost to the health care system is rising. In order to promote innovative research in asthma therapies, the National Heart, Lung and Blood Institute created the Childhood Asthma Research and Education Network in 1999. As its first study, the steering committee of the Childhood Asthma Research and Education Network designed a randomized clinical trial to determine if persistent asthma could be prevented in children at a high risk to develop the disease. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.03.002DOI Listing
June 2004
26 Reads

Quality of life intervention for prostate cancer patients: design and baseline characteristics of the active for life after cancer trial.

Control Clin Trials 2004 Jun;25(3):265-85

Department of Behavioral Science-243, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030-4095, USA.

Prostate cancer patients receiving androgen ablation therapy experience significant physical and psychological sequelae associated with their disease and treatment. Because physical activity improves physical and psychological well-being, a lifestyle physical activity intervention may help slow or reverse the associated decline in quality of life (QOL). No studies have evaluated an intervention to improve multiple QOL domains in patients receiving androgen ablation therapy. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2004.03.001DOI Listing
June 2004
8 Reads

Widening eligibility to phase II trials: constant arcsine difference phase II trials.

Authors:
Roger P A'Hern

Control Clin Trials 2004 Jun;25(3):251-64

Department of Information, Royal Marsden NHS Trust, Fulham Road, London SW3 6JJ, United Kingdom.

This paper presents a method for undertaking Phase II trials in which not all patients are considered equally likely to respond to treatment. In ovarian cancer, for example, it has been shown that response is less likely in patients who have failed the previous treatment after only a short interval compared to those who have a protracted failure-free interval [Gynecol. Oncol. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2003.12.001DOI Listing
June 2004
4 Reads

Mounting a community-randomized trial: sample size, matching, selection, and randomization issues in PRISM.

Control Clin Trials 2004 Jun;25(3):235-50

Centre for the Study of Mothers' and Children's Health, La Trobe University, Bundoora Victoria, 3083, Australia.

This paper discusses some of the processes for establishing a large cluster-randomized trial of a community and primary care intervention in 16 local government areas in Victoria, Australia. The development of the trial in terms of design factors such as sample size estimates and the selection and randomization of communities to intervention or comparison is described. The intervention program to be implemented in Program of Resources, Information and Support for Mothers (PRISM) was conceived as a whole community approach to improving support for all mothers in the first 12 months after birth. Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560400028
Publisher Site
http://dx.doi.org/10.1016/j.cct.2003.12.002DOI Listing
June 2004
6 Reads

Sequenced treatment alternatives to relieve depression (STAR*D): rationale and design.

Control Clin Trials 2004 Feb;25(1):119-42

Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9086, USA.

STAR*D is a multisite, prospective, randomized, multistep clinical trial of outpatients with nonpsychotic major depressive disorder. The study compares various treatment options for those who do not attain a satisfactory response with citalopram, a selective serotonin reuptake inhibitor antidepressant. The study enrolls 4000 adults (ages 18-75) from both primary and specialty care practices who have not had either a prior inadequate response or clear-cut intolerance to a robust trial of protocol treatments during the current major depressive episode. Read More

View Article

Download full-text PDF

Source
https://xa.yimg.com/kq/groups/19525360/1899315440/name/fulte
Web Search
February 2004
19 Reads

Preventing chronic ectopic bone-related pain and disability after hip replacement surgery with perioperative ibuprofen. A multicenter, randomized, double-blind, placebo-controlled trial (HIPAID).

Control Clin Trials 2004 Apr;25(2):223-33

Institute for International Health, University of Sydney, P.O. Box 576, Newtown, Sydney, NSW 2042, Australia.

Postoperative ectopic bone formation affects about 40% of people undergoing elective hip replacement surgery. Despite clear evidence that a short course of perioperative nonsteroidal anti-inflammatory drugs (NSAIDs) can substantially reduce the occurrence of ectopic bone, the use of NSAID-based prophylactic therapy is uncommon in Australia or New Zealand. In part, this reflects surgeons' uncertainty about the importance of ectopic bone as a cause of impaired long-term outcome, and in part, concerns about possible increased risk for gastrointestinal complications and excess wound bleeding in patients undergoing orthopedic surgery. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2003.11.008DOI Listing
April 2004
7 Reads

Implementation of the Prostate Cancer Prevention Trial (PCPT).

Control Clin Trials 2004 Apr;25(2):203-22

Southwest Oncology Group Statistical Center, M/S M3-C102, 1100 Fairview Avenue North, Box 19024, Seattle, WA 98109-1024, USA.

The Prostate Cancer Prevention Trial is a randomized double blind chemoprevention trial of 18,882 men. It is designed to test the difference in the histologically proven prostate cancer prevalence between a group of participants given finasteride and another given placebo for 7 years. We present an overview of the study design, details of the administrative structure of the study and a description of the successful implementation of the accrual phase. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2003.11.007DOI Listing
April 2004
7 Reads

The UCSD Statin Study: a randomized controlled trial assessing the impact of statins on selected noncardiac outcomes.

Control Clin Trials 2004 Apr;25(2):178-202

Department of Medicine, University of California, San Diego School of Medicine, San Diego, CA 92093-0995, USA.

There has been persistent controversy regarding possible favorable or adverse effects of statins or of cholesterol reduction on cognition, mood and behavior (including aggressive or violent behavior), muscle function, and quality of life. The UCSD Statin Study seeks to ascertain the beneficial or adverse effects of statin cholesterol-lowering drugs on a set of noncardiac endpoints, including cognition, behavior, and serotonin biochemistry. The study will enroll 1000 subjects (minimum 20% female) of mixed ethnicity from San Diego. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2003.08.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4285453PMC
April 2004
7 Reads

Comparing the power of the discontinuation design to that of the classic randomized design on time-to-event endpoints.

Authors:
William B Capra

Control Clin Trials 2004 Apr;25(2):168-77

Department of Biostatistics and Clinical Data Management, Chiron Corporation, 4560 Horton Street, M/S U-120, Emeryville, CA 94608-2916, USA.

The discontinuation design has been proposed as an alternative to the classic randomized design for evaluating the effect of an experimental agent on time-to-disease progression and survival duration. With this design, all enrolled patients are treated with an experimental agent for a fixed course of therapy. Those patients with progressive disease at or before the end of this fixed period are removed from trial while those with stable disease or better are randomized to continued treatment with the experimental agent or standard of care. Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560300178
Publisher Site
http://dx.doi.org/10.1016/j.cct.2003.11.005DOI Listing
April 2004
5 Reads

Bayesian sample size calculations in phase II clinical trials using informative conjugate priors.

Control Clin Trials 2004 Apr;25(2):157-67

Department of Preventive Medicine and Public Health, Medical Statistics and Research Design Unit, Kansas Cancer Institute, University of Kansas Medical Center, Kansas City, KS, USA.

A number of researchers have discussed phase II clinical trials from a Bayesian perspective. A recent article by Tan and Machin focuses on sample size calculations, which they determine by specifying a diffuse prior distribution and then calculating a posterior probability that the true response will exceed a prespecified target. In this article, we extend these sample size calculations to include informative prior distributions using various strategies that allow researchers with both optimistic and pessimistic priors direct involvement in the sample size decision making. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2003.11.006DOI Listing
April 2004
5 Reads

Assessment of blinding in clinical trials.

Control Clin Trials 2004 Apr;25(2):143-56

Department of Biostatistics, University of North Carolina at Chapel Hill, 137 E. Franklin Street, Chapel Hill, NC 27599, USA.

Success of blinding is a fundamental issue in many clinical trials. The validity of a trial may be questioned if this important assumption is violated. Although thousands of ostensibly double-blind trials are conducted annually and investigators acknowledge the importance of blinding, attempts to measure the effectiveness of blinding are rarely discussed. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2003.10.016DOI Listing
April 2004
8 Reads

Medicine or Surgery (Ms): a randomized clinical trial comparing hysterectomy and medical treatment in premenopausal women with abnormal uterine bleeding.

Control Clin Trials 2004 Feb;25(1):104-18

Department of Obstetrics and Gynecology, University of Alabama at Birmingham, 619 South 19th Street, NHB-219, Birmingham, AL 35249-7333, USA.

Hysterectomy may be overused as treatment for abnormal uterine bleeding due to benign causes in reproductive women. Medical therapies are an alternative, and there is a need for randomized trials comparing the outcomes of these approaches. Women of reproductive age who continued to have bothersome abnormal uterine bleeding after cyclic hormonal treatment with medroxyprogesterone acetate (MPA; 10-20 mg for 10-14 days/month) for 3-5 months were invited to participate in a randomized trial of hysterectomy versus other medical therapies. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2003.08.008DOI Listing
February 2004
9 Reads

Stop Hypertension with the Acupuncture Research Program (SHARP): clinical trial design and screening results.

Control Clin Trials 2004 Feb;25(1):76-103

New England Research Institutes, 9 Galen Street, Watertown, MA 02472, USA.

Hypertension is a major public health problem with serious medical and financial consequences. Barriers to successful conventional pharmacological treatment include side effects, out-of-pocket expenses, patient noncompliance and insufficient dosages. Acupuncture has been studied as an alternative therapy for controlling blood pressure (BP) but previous studies have serious methodological limitations. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2003.08.006DOI Listing
February 2004
54 Reads
17 Citations

Assessing patient comprehension of informed consent forms.

Authors:
Jessica Ancker

Control Clin Trials 2004 Feb;25(1):72-4; author reply 74-5

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2003.10.003DOI Listing
February 2004
4 Reads

Stopping rules for clinical trials.

Authors:
John Whitehead

Control Clin Trials 2004 Feb;25(1):69-70; author reply 71-2

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/S0197-2456(03)00110-7DOI Listing
February 2004
5 Reads

Data monitoring and large apparent treatment effects.

Control Clin Trials 2004 Feb;25(1):67-9; author reply 71-2

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/S0197-2456(03)00109-0DOI Listing
February 2004
5 Reads

A randomized controlled trial of the effects of nurse case manager and community health worker team interventions in urban African-Americans with type 2 diabetes.

Control Clin Trials 2004 Feb;25(1):53-66

Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Room E6034, Baltimore, MD 21205, USA.

The objective of the study was to determine the effectiveness and cost-effectiveness of primary care and community-oriented interventions in managing HbA1c, blood pressure, and lipids, and reducing hospitalizations and emergency room visits over 2 years. We describe an ongoing, randomized controlled trial of 542 urban African-Americans with type 2 diabetes ages 25 years and older who are members of a university-affiliated managed-care organization in Baltimore, MD. The participants are 74% female, have a mean age of 58 years, and 35% have yearly incomes greater than 7500 US dollars. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2003.10.010DOI Listing
February 2004
10 Reads

Follow-up by mail in clinical trials: does questionnaire length matter?

Control Clin Trials 2004 Feb;25(1):31-52

CRASH Trial Co-ordinating Centre, Department of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, 49-51 Bedford Square London, WC1B 3DP, UK.

In large clinical trials where outcome assessment is possible using questionnaires, it may be more cost-effective to mail them to patients than to conduct interviews in-person. However, nonresponse to mailed questionnaires reduces the effective sample size and can introduce bias. We conducted a systematic review and meta-analysis of randomized controlled trials evaluating the effect of questionnaire length on response rates. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2003.08.013DOI Listing
February 2004
6 Reads

Applying linear mixed models to estimate reliability in clinical trial data with repeated measurements.

Control Clin Trials 2004 Feb;25(1):13-30

Johnson & Johnson Pharmaceutical Research and Development, Beerse, Belgium.

Repeated measures are exploited to study reliability in the context of psychiatric health sciences. It is shown how test-retest reliability can be derived using linear mixed models when the scale is continuous or quasi-continuous. The advantage of this approach is that the full modeling power of mixed models can be used. Read More

View Article

Download full-text PDF

Source
http://linkinghub.elsevier.com/retrieve/pii/S019724560300133
Publisher Site
http://dx.doi.org/10.1016/j.cct.2003.08.009DOI Listing
February 2004
18 Reads

A simple alternative confidence interval for the difference between two proportions.

Control Clin Trials 2004 Feb;25(1):3-12

Robarts Clinical Trials, Robarts Research Institute, London, Ontario, Canada N6A 5K8.

The difference between two proportions is often the focus of interest in prospective comparative studies such as randomized controlled trials that have a binary outcome. Consequently, interval estimation for this parameter has received considerable attention in the literature. A hybrid procedure resulting from combining two sets of confidence limits for a single proportion as proposed by Newcombe has been previously recommended for this purpose because of its superior properties and relative simplicity. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cct.2003.08.010DOI Listing
February 2004
5 Reads

The Italian-American Clinical Trial of Nutritional Supplements and Age-Related Cataract (CTNS): design implications. CTNS report no. 1.

Authors:

Control Clin Trials 2003 Dec;24(6):815-29

The Italian-American Clinical Trial of Nutritional Supplements and Age-Related Cataract (CTNS) is a 13-year study designed primarily to evaluate the safety and efficacy of a vitamin-mineral supplement containing recommended daily allowance (RDA) dosages in preventing age-related cataract or delaying its progression. As secondary objectives the study will collect data on incidence and progression rates as well as risk factors for the disease. The clinical trial was initiated largely because of epidemiological studies suggesting that various nutrients, particularly those with antioxidant capabilities, might retard cataract development. Read More

View Article

Download full-text PDF

Source
December 2003
8 Reads

The Children's Amalgam Trial: design and methods.

Authors:

Control Clin Trials 2003 Dec;24(6):795-814

The safety of silver amalgam as a dental restorative material has been controversial since its introduction 150 years ago, but until recently it has been assumed that the exposure to mercury from dental amalgam is limited to the acute placement phase. However, some recent studies have raised safety concerns by demonstrating chronic release of mercury vapor from amalgam fillings during chewing and brushing. The Children's Amalgam Trial is a two-arm randomized trial of safety, comparing amalgam with a mercury-free restorative material. Read More

View Article

Download full-text PDF

Source
December 2003
7 Reads

Evaluation of outcome and cost-effectiveness using an FDG PET-guided approach to management of patients with coronary disease and severe left ventricular dysfunction (PARR-2): rationale, design, and methods.

Control Clin Trials 2003 Dec;24(6):776-94

Cardiac PET Center, Divisions of Cardiology and Cardiac Surgery, University of Ottawa Heart Institute, Ottawa, Ontario, Canada.

Patients with severe ventricular dysfunction and coronary disease have high morbidity and mortality. They may benefit from revascularization but have significant perioperative morbidity and mortality. Positron emission tomography (PET) imaging with F-18-fluorodeoxyglucose (FDG) can detect viable myocardium that may recover from revascularization in such patients. Read More

View Article

Download full-text PDF

Source
December 2003
9 Reads

The Osteoporosis Prevention and Arterial effects of tiboLone (OPAL) study: design and baseline characteristics.

Control Clin Trials 2003 Dec;24(6):752-75

Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands.

The Osteoporosis Prevention and Arterial effects of tiboLone (OPAL) trial is a three-arm, randomized, placebo-controlled, double-blind study to determine the effect of tibolone 2.5 mg (Org OD 14) and continuous combined conjugated equine estrogens plus medroxyprogesterone acetate (0.625 mg/2. Read More

View Article

Download full-text PDF

Source
December 2003
5 Reads