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PubMed2005

Design of the BiRmingham Early Detection In untREated psyChosis Trial (REDIRECT): cluster randomised controlled trial of general practitioner education in detection of first episode psychosis [ISRCTN87898421].

BACKGROUND: Treatment delay in first episode psychosis is common. As general practitioners are the first point of contact for many individuals with first episode psychosis, they are well placed to detect the early symptoms and make urgent referrals to specialist secondary care services. However, early psychosis is often difficult to detect. The primary objective of the Redirect trial is to estimate whether an educational intervention targeted at general practitioners increases the general practitioner referral rate of young people with first episode psychosis to Early Intervention Services. METHODS/DESIGN: This paper describes the design of a stratified-cluster randomised controlled trial of an educational intervention on first episode psychosis in primary care. The primary outcome is the number of general practitioner referrals of young people with first episode psychosis to Early Intervention Services. Secondary outcomes are duration of untreated psychosis, time to recovery, use of the Mental Health Act, and general practitioner consultation rate. Young people with first episode psychosis referred to Early Intervention Services will be recruited over a two-year period from 1 March 2004. Seventy-eight out of 89 eligible general practices were recruited. The educational intervention has been implemented and evaluated by general practitioners. The education was well received and considered relevant to clinical practice by the general practitioners. DISCUSSION: The results suggest that the recruitment strategy and implementation of the educational intervention are feasible and acceptable in a primary care setting. The Redirect trial will provide robust information about the efficacy of an evidence-based complex educational intervention targeted at general practitioners on referral rates of young people with first episode psychosis to Early Intervention Services.

Adolescent↗

PubMed2006

The DAMASK trial protocol: a pragmatic randomised trial to evaluate whether GPs should have direct access to MRI for patients with suspected internal derangement of the knee.

BACKGROUND: Though new technologies like Magnetic Resonance Imaging (MRI) may be accurate, they often diffuse into practice before thorough assessment of their value in diagnosis and management, and of their effects on patient outcome and costs. MRI of the knee is a common investigation despite concern that it is not always appropriate. There is wide variation in general practitioners (GPs) access to, and use of MRI, and in the associated costs. The objective of this study was to resolve uncertainty whether GPs should refer patients with suspected internal derangement of the knee for MRI or to an orthopaedic specialist in secondary care. METHODS/DESIGN: The design consisted of a pragmatic multi-centre randomised trial with two parallel groups and concomitant economic evaluation. Patients presenting in general practice with suspected internal derangement of the knee and for whom their GP was considering referral to an orthopaedic specialist in secondary care were eligible for inclusion. Within practices, GPs or practice nurses randomised eligible and consenting participants to the local radiology department for an MRI examination, or for consultation with an orthopaedic specialist. To ensure that the waiting time from GP consultation to orthopaedic appointment was similar for both trial arms, GPs made a provisional referral to orthopaedics when requesting the MRI examination. Thus we evaluated the more appropriate sequence of events independent of variations in waiting times. Follow up of participants was by postal questionnaires at six, twelve and 24 months after randomisation. This was to ensure that the evaluation covered all events up to and including arthroscopy. DISCUSSION: The DAMASK trial should make a major contribution to the development of evidence-based partnerships between primary and secondary care professionals and inform the debate when MRI should enter the diagnostic pathway.

Adolescent↗

PubMed2006

Fatigue Intervention by Nurses Evaluation--the FINE Trial. A randomised controlled trial of nurse led self-help treatment for patients in primary care with chronic fatigue syndrome: study protocol. [ISRCTN74156610].

BACKGROUND: Chronic fatigue syndrome, also known as ME (CFS/ME), is a condition characterised primarily by severe, disabling fatigue, of unknown origin, which has a poor prognosis and serious personal and economic consequences. Evidence for the effectiveness of any treatment for CFS/ME in primary care, where most patients are seen, is sparse. Recently, a brief, pragmatic treatment for CFS/ME, based on a physiological dysregulation model of the condition, was shown to be successful in improving fatigue and physical functioning in patients in secondary care. The treatment involves providing patients with a readily understandable explanation of their symptoms, from which flows the rationale for a graded rehabilitative plan, developed collaboratively with the therapist. The present trial will test the effectiveness and cost-effectiveness of pragmatic rehabilitation when delivered by specially trained general nurses in primary care. We selected a client-centred counselling intervention, called supportive listening, as a comparison treatment. Counselling has been shown to be as effective as cognitive behaviour therapy for treating fatigue in primary care, is more readily available, and controls for supportive therapist contact time. Our control condition is treatment as usual by the general practitioner (GP). METHODS AND DESIGN: This study protocol describes the design of an ongoing, single-blind, pragmatic randomized controlled trial of a brief (18 week) self-help treatment, pragmatic rehabilitation, delivered by specially trained nurse-therapists in patients' homes, compared with nurse-therapist delivered supportive listening and treatment as usual by the GP. An economic evaluation, taking a societal viewpoint, is being carried out alongside the clinical trial. Three adult general nurses were trained over a six month period to deliver the two interventions. Patients aged over 18 and fulfilling the Oxford criteria for CFS are assessed at baseline, after the intervention, and again one year later. Primary outcomes are self-reported physical functioning and fatigue at one year, and will be analysed on an intention-to-treat basis. A qualitative study will examine the interventions' mechanisms of change, and also GPs' drivers and barriers towards referral.

Clinical Protocols↗

PubMed2003

Imaging in antiangiogenesis trial: a clinical trials radiology perspective.

Traditional approaches for treating cancer have largely focused on the ability of chemotherapy, and to a lesser extent radiation therapy, to destroy tumour cells. Recent developments in antiangiogenesis treatments require a fundamental shift in the radiological and imaging paradigms associated with evaluating response. Proper design and execution of any clinical trial involving imaging angiogenesis requires satisfactory consideration of a number of strategies and an in-depth understanding of different imaging techniques such as dynamic contrast enhanced MRI and CT, contrast-enhanced ultrasound and positron emission tomography. In particular, for imaging, the strategies can be divided into issues that need to be addressed during the protocol planning phase, and strategies that need to be addressed during the execution phase. Furthermore, clinical trials are usually subject to stringent regulations surrounding traceability and reproducibility that need to be followed before the regulatory authorities will accept the integrity of the data. This paper elaborates on the above strategies and outlines certain aspects, or tactics, that need to be considered while preparing for a multicentre clinical trial that involves imaging angiogenesis.

Angiogenesis Inhibitors↗

PubMed1993

Glomerular filtration rate measurements in clinical trials. Modification of Diet in Renal Disease Study Group and the Diabetes Control and Complications Trial Research Group.

To assess the utility and precision of GFR measurements in multicenter trials, the test performance and variability of GFR were analyzed in 2,250 patients enrolled in 44 clinical centers participating in either the Modification of Diet in Renal Disease (MDRD) Study or the Diabetes Control and Complications Trial (DCCT). GRF was measured as the renal clearance of [125I]iothalamate after an sc injection without epinephrine. The studies used similar protocols for obtaining blood and urine, training clinical center staff, and processing specimens in central laboratories. The performance of GFR measurements, assessed from adherence to protocol and quality control analyses, was excellent. The variability among the four clearance periods (intratest coefficient of variation [CV]) was acceptable; the median intratest CV for GFR was 9.4% in the MDRD Study and 11.7% in the DCCT. The pattern of decline in serum counts was better approximated by an exponential rather than a linear relationship. The cause of the intratest variability in GFR measurements was explored by univariate and multivariate analysis. The intratest CV was highest at the extremes of GFR. Among patients with a high GFR (> 90 mL/min per 1.73 m2), most of whom were participants in the DCCT, the higher intratest GFR was due, in part, to a systematic decline in GFR during the test. Among patients with a very low GFR (< 13 mL/min per 1.73 m2), technical difficulties in urine collections contributed substantially to the higher intratest CV. Other patient characteristics, including age, gender, weight, serum glucose, renal diagnosis, and use of diuretics, were not strongly correlated with the intratest CV. The precision of GFR measurements was assessed from the variability from measurement to measurement (interest CV). Among MDRD Study subjects, in whom two measurements of GFR were performed over a 3-month interval, the median interest CV was relatively low (6.3%) and was only weakly related to the intratest CV. Thus, GFR measurements are reasonably precise, even if the intratest CV is high. Given the relatively high intratest CV that is characteristic of GFR measurements, the estimate of GFR in an individual is more precise if multiple clearance periods, rather than a single period, are included. Similarly, the estimate of mean GFR for a population is also more precise if multiple clearance periods are included. In conclusion, by the use of standardized methods, an acceptable precision of GFR results can be obtained in multicenter trials. The same methods can be applied in clinical practice.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

PubMed1999

Clinical economics in clinical trials: the measurement of cost and outcomes in the assessment of clinical services through clinical trials.

As the population ages and more expensive high-technology services become available, health care costs continue to spiral upward. Because the financial resources for health care are limited, economic analysis can help to evaluate expenditures and set priorities. Economic analysis of medical technology or medical care evaluates a medical service by comparing its dollar cost with its dollar benefit (cost-benefit), by measuring its dollar cost in relation to its outcomes (cost-effectiveness) as well as in relation to its utility or quality-adjusted outcomes (cost-utility), or simply by tabulating the costs involved (cost-identification). Direct costs are generated as services are provided. In addition, patients' productivity is affected, and these costs can be considered, especially in determining the benefit of a service that decreases morbidity or mortality. Intangible costs are those of pain, suffering, and grief. The point of view, or perspective, of the study determines the costs and benefits that will be measured in the analysis. Sensitivity analysis, which can evaluate the stability of the conclusions to the data used, is an important assessment within economic analysis. Economic analysis of new pharmaceutical therapies is increasingly being incorporated into clinical trials. Although there are some limitations of pharmacoeconomic information in clinical studies of drug safety and efficacy, these trials are often the only opportunity for economic data collection before adoption and reimbursement decisions are made. Validation after the drug has been introduced should complement economic information developed from clinical trials.

Clinical Trials as Topic↗

PubMed2006

Improving the quality of randomized controlled trials in Chinese herbal medicine, part III: quality control of Chinese herbal medicine used in randomized controlled trials.

OBJECTIVE: To discuss quality control of Chinese herbal medicine (CHM) in randomized controlled trials (RCTs), and to provide suggestions for improving this aspect in future clinical study in this therapeutic area. METHODS: A search of the Cochrane Library was conducted to identify RCTs of CHM. Quality control information reported in those RCTs was then assessed independently. RESULTS: The search yielded a total of 167 RCTs of CHM for a variety of conditions. A total of 11 CHM preparations were used in those RCTs. Only one trial discussed quality control of the CHM interventions used. Issues affecting the safety and efficacy of CHM products used in RCTs were discussed including standardization of raw herbal materials, processing methods, screening for product contamination, and effects of combination products. CONCLUSION: The overall quality of reporting of RCTs of CHM was poor, reflecting the need for improvements in reporting future clinical trials in this area. RECOMMENDATIONS: To improve quality control of CHM used in RCTs in future, we recommend developing and implementing guidelines such as Good Agricultural Practice (GAP) for Chinese crude drugs, and current Good Manufacturing Practice (GMP) specific to CHM products. Chemical analyses of individual herbs of CHM and combination products are also recommended to provide reference standards for quality control.

Drugs, Chinese Herbal↗

PubMed2000

Trials with errors--preserving the integrity of clinical trials.

The crucial final test of medical research is the clinical trial, which determines whether a drug or discovery really is an effective therapy. All people who participate in clinical trials--researchers, sponsors, volunteers, analysts, reviewers, overseers, others--have opportunities to strengthen or weaken the integrity of the trial system by their behavior. Medical research is now officially married to business, and "profitable" connotes something different to each partner. Only if research and business can profit in parallel will the alliance succeed. Every person who is involved in the medical research business faces temptations and must choose how to react. Each has power and must choose how to wield it. Several centuries before this marriage, the Englishman Izaak Walton noted that "Health is...a blessing that money cannot buy."

Clinical Trials as Topic↗

PubMed1998

Freebies for subject 641: a discussion of the ethical prospect of providing drug trial subjects with post-trial access to the drug tested--a Canadian perspective.

"Pharmaceutical Company Incorporated" is developing a new drugs to treat AIDS. The Company is hoping to begin clinical trials soon and has submitted its tiral proposal for consideration by the Research Ethics Board (REB). The proposal includes provision to supply the drug free of charge to trial subjects if the drug is shown to be effective and safe. The members of the REB are split as to whether such an offer is acceptable. Some members of the REB are concerned that the offer is an undue inducement for prospective subjects to participate in the clinical trial.

Canada↗

PubMed1992

Osteoarthritis antirheumatic drug trials. III. Setting the delta for clinical trials--results of a consensus development (Delphi) exercise.

Defining the minimum clinically important difference or delta to be detected in a clinical trial depends on a number of factors including the research hypothesis, patient characteristics, the nature of the intervention and the trial design. In 2 studies, we have developed standardized procedures for conducting outcome measurement based on current Food and Drug Administration and European League Against Rheumatism guidelines for osteoarthritis clinical trials, and determined the standard deviation for these outcome measures. In the final component of this series of studies, we have used a Delphi technique to establish estimates for delta, and calculated the sample size requirements under 2 different conditions of Type I and Type II error probabilities.

Clinical Trials as Topic↗

PubMed2000

Mortality in two recent reports of clinical trials on patients with congestive heart failure compared with mortality in three previous clinical trials.

BACKGROUND: Several clinical trials of drug treatment of patients with congestive heart failure (CHF) have previously been reported as Mortality Abstracts in the Journal of Insurance Medicine. Results are presented here for two similar clinical trials reported in September 1999 and compared with the previous results. RESULTS: In a recent international multicenter clinical trial, excess mortality in terms of excess death rates (EDRs) was reduced from 195 per 1000 per year in the placebo group to 139 in the group treated with Spironolactone. There was no significant reduction in the Danish multicenter study of Dofetilide to convert the atrial fibrillation (AF) to a normal rhythm in the 25% of the CHF patients who had AF (EDR was 224 in the placebo group and 216 in the Dofetilide group). In both of these studies, there were more patients with severe CHF than in the previous studies and the EDR values were higher. Results from the Danish study by severity according to the New York Heart Association (NYHA) classification show a progressive increase in EDR from 173 in class 2 to 237 in class 3 to 392 in class 4. CONCLUSION: Excess mortality in symptomatic CHF is far outside the issue limits for individual life insurance, but these results are of potential utility for the underwriting of such cases for structured settlement annuities.

Aged↗

PubMed2006

Recruitment of African American and white postmenopausal women into clinical trials: the beneficial effects of soy trial experience.

OBJECTIVE: To describe the strategies and costs associated with recruiting both African American and White postmenopausal women into a randomized controlled trial. DESIGN: The Beneficial Effects of Soy Trial (BEST) was a randomized, controlled trial designed to determine the effects of a dietary soy supplement on lipoproteins, lipoprotein subclasses, and menopausal symptoms in African American and White postmenopausal women. The goal was to have > or = 80 African American and > or = 80 White women complete the study. RESULTS: A total of 705 postmenopausal women (381 African American, 324 White) were screened, and of those, 217 were randomized (105 African American, 112 White), and 192 (91 African American, 101 White) completed the study. Direct mailings to targeted zip codes proved the most successful recruitment strategy for recruiting African Americans (52% of African Americans recruited) and the second most effective for recruiting Whites (32% of Whites recruited). Newspaper advertisements yielded the highest number of White participants (36%) but proved less successful for recruiting African Americans (8%). Airing advertisements on the radio was the second most effective strategy for recruiting African Americans (15%), yet it was one of the least effective approaches for recruiting Whites (5%). The total cost of recruitment was dollar 49,036.25, which averaged dollar 255.40 per participant who completed the study. The three most successful strategies, direct mailings, newspaper ads, and radio ads, were the three most expensive approaches but yielded 73% of all participants who completed the study.

Black or African American↗

PubMed1991

Ankylosing spondylitis antirheumatic drug trials. III. Setting the delta for clinical trials of antirheumatic drugs--results of a consensus development (Delphi) exercise.

Defining the minimum clinically important difference or delta to be detected in a clinical trial depends on a number of factors including the research hypothesis, patient characteristics, the nature of the intervention and the trial design. In 2 previous studies, we have developed standardized procedures for conducting outcome measurement based on current Food and Drug Administration and European League Against Rheumatism guidelines for clinical trials in ankylosing spondylitis, and thereafter, determined the standard deviation for these outcome measures. In the final component of this series of studies, we have employed a Delphi technique to establish estimates for delta, and calculated the sample size requirements under 2 different conditions of Type I and Type II error probabilities.

Anti-Inflammatory Agents↗

PubMed1991

Rheumatoid arthritis antirheumatic drug trials. III. Setting the delta for clinical trials of antirheumatic drugs--results of a consensus development (Delphi) exercise.

Defining the minimum clinically important difference or delta to be detected in a clinical trial depends on a number of factors including the research hypothesis, patient characteristics, the nature of the intervention and the trial design. In 2 previous studies, we have developed standardized procedures for conducting outcome measurement based on current Food and Drug Administration and European League Against Rheumatism guidelines for RA clinical trials, and thereafter, determined the standard deviation for these outcome measures. In the final component of this series of studies, we employed a Delphi technique to establish estimates for delta and calculated the sample size requirements under different conditions of Type I and Type II error probabilities.

Arthritis, Rheumatoid↗

PubMed1995

Overview of randomized trials of angiotensin-converting enzyme inhibitors on mortality and morbidity in patients with heart failure. Collaborative Group on ACE Inhibitor Trials.

OBJECTIVE: To evaluate the effect of angiotensin-converting enzyme (ACE) inhibitors on mortality and morbidity in patients with symptomatic congestive heart failure. DATA SOURCE AND STUDY SELECTION: Data were obtained for all completed, published or unpublished, randomized, placebo-controlled trials of ACE inhibitors that were at least 8 weeks in duration and had determined total mortality by intention to treat, regardless of sample size. Trials were identified based on literature review and correspondence with investigators and pharmaceutical firms. DATA EXTRACTION: Using standard tables, data were extracted by one author and confirmed where necessary by the other author or the principal investigator of the trial. Unpublished data were obtained by direct correspondence with the principal investigator of each study or pharmaceutical firm. DATA SYNTHESIS: The data for each outcome were combined using the Yusuf-Peto adaptation of the Mantel-Haenszel method. Overall, there was a statistically significant reduction in total mortality (odds ratio [OR], 0.77; 95% confidence interval [CI], 0.67 to 0.88; P < .001) and in the combined endpoint of mortality or hospitalization for congestive heart failure (OR, 0.65; 95% CI, 0.57 to 0.74; P < .001). Similar benefits were observed with several different ACE inhibitors, although the data were largely based on enalapril maleate, captopril, ramipril, quinapril hydrochloride, and lisinopril. Reductions for total mortality and the combined endpoint were similar for various subgroups examined (age, sex, etiology, and New York Heart Association class). However, patients with the lowest ejection fraction appeared to have the greatest benefit. The greatest effect was seen during the first 3 months, but additional benefit was observed during further treatment. The reduction in mortality was primarily due to fewer deaths from progressive heart failure (OR, 0.69; 95% CI, 0.58 to 0.83); point estimates for effects on sudden or presumed arrhythmic deaths (OR, 0.91; 95% CI, 0.73 to 1.12) and fatal myocardial infarction (OR, 0.82; 95% CI, 0.60 to 1.11) were less than 1 but were not significant. CONCLUSIONS: Total mortality and hospitalization for congestive heart failure are significantly reduced by ACE inhibitors with consistent effects in a broad range of patients.

Aged↗

PubMed1996

Drug treatment of functional dyspepsia: a systematic analysis of trial methodology with recommendations for design of future trials.

OBJECTIVES: To evaluate drug treatment of functional dyspepsia (including Helicobacter pylori) and provide guidelines for future trials based on a critical systematic overview of published studies. METHODS: Data sources were a Medline search for articles published in English going back to 1966 and a manual search of four GI journals going back to 1980. Original randomized, double-blind, placebo-controlled trials were selected that enrolled at least 20 patients. Using a standardized, pretested data extraction form, studies were evaluated independently by two observers for study design, outcome measures, and results. RESULTS: Fifty two eligible studies were evaluated. Many studies suffered from important weaknesses in study design and execution. Only five studies used previously validated outcome measures. CONCLUSIONS: Because of suboptimal design and/or unclear presentation of the data, none of the trials provided unequivocal evidence that there is efficacious therapy for the treatment of functional dyspepsia.

Double-Blind Method↗

PubMed1992

Studies of ocular complications of AIDS Foscarnet-Ganciclovir Cytomegalovirus Retinitis Trial: 1. Rationale, design, and methods. AIDS Clinical Trials Group (ACTG).

Cytomegalovirus (CMV) retinitis is the most common intraocular infection in patients with AIDS and affects an estimated 20% of these patients. Two drugs, ganciclovir and foscarnet, are currently available for the treatment of CMV retinitis. The Foscarnet-Ganciclovir CMV Retinitis Trial was designed: (1) to evaluate the relative efficacy and safety of foscarnet and ganciclovir for the treatment of CMV retinitis in patients with AIDS; and (2) to compare the relative benefits of immediate treatment versus deferral of the treatment for patients with disease not involving the posterior pole. Prior to randomization, patients were assigned to one of two strata based upon the location and extent of retinitis in the more severely involved eye. Patients with retinitis in zone 1 (posterior pole) or extensive retinitis (extent greater than or equal to 25% retina) in zones 2 and/or 3 (peripheral retina) were randomly assigned to immediate treatment with either ganciclovir or foscarnet. Patients with CMV retinitis confined to less than or equal to 25% of the retina and in zones 2 and/or 3 were offered the option of participating in the comparison of immediate treatment versus deferral of treatment. Patients opting to participate in this comparison were randomly assigned to immediate treatment versus deferral. Patients preferring to choose either immediate treatment or deferral (treatment preference design) were randomized only to foscarnet or ganciclovir for treatment of CMV retinitis. Patients in the deferral group were started on drug treatment when the retinitis became more immediately sight-threatening either by virtue of location (involvement of zone 1) or size (extent greater than 25% of the retina). Outcome measures included: survival, retinitis progression, visual function (visual acuity and visual field), drug side effects, and morbidity. Enrollment in the trial began in March 1990 and was completed in October 1991.

Acquired Immunodeficiency Syndrome↗

PubMed1995

Trials of Hypertension Prevention, phase II. Structure and content of the weight loss and dietary sodium reduction interventions. Trials of Hypertension Prevention (TOHP) Collaborative Research Group.

Identifying effective, nonpharmacologic means of preventing or significantly delaying the onset of hypertension would be a major advance in the primary prevention of cardiovascular disease. In the first phase of the Trials of Hypertension Prevention (TOHP I), adults with high-normal diastolic blood pressure were randomly assigned to one of seven nonpharmacologic interventions. Only weight loss and reduction of dietary sodium proved to be effective strategies for reducing blood pressure. The second phase of TOHP (TOHP II) will test the effectiveness of weight loss, reduction of dietary sodium, and their combination of lowering blood pressure and preventing the onset of hypertension over a 3- to 4-year follow-up period. This article describes the three interventions used in TOHP II, methods used to maintain continued participation in this long-term trial, and protocol enhancements designed to maximize intervention effectiveness.

Adult↗