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In Phase II oncology studies, response rate has traditionally been used to assess activity. However stabilization of disease (SD) may also provide patient benefit. To assess the value of SD (stabilization of measurable disease for at least 8 weeks) as a predictor of survival following chemotherapy in patients with non-small cell lung cancer (NSCLC), we have analyzed data from 198 NSCLC patients receiving topotecan i.v. or orally as first-line therapy either as single agent or in combination. Proportional hazards (Cox) regression models showed that responders [complete response (CR) + partial response (PR), 1.5% and 11.6% respectively] had an estimated risk of death that was 9.8% (95% CI: 4.2% to 22.7%) of that for progressive disease (PD) (60.1% of the patient population). Similarly, patients with SD (26.8% of the patient population) showed a potential benefit with a risk of death that was 27.7% of the one of patients with PD (95% CI: 17.8% to 43.1%). In conclusion SD may be a useful indicator of patient benefit from chemotherapy for NSCLC.
BACKGROUND: The benefits of new technology steadily being introduced in medicine should be documented. In this study, remote entry of a set of data from the daily routine was submitted via the Internet to a common database. The usefulness and quality of the information are evaluated. METHODS: Fourteen hospitals reported a common data set on consecutive Hp+ve patients handled in accordance with daily practice. Participants submitted their data via the Internet to a database. There was no monitoring or other surveillance. No audit was planned or expected, but was nevertheless possible. Doctor compliance with the common agreement was checked, differences in medical practice were noted and quality was assessed comparing the most important source data with the data in the final database. RESULTS: Four-hundred-and-forty patients were included. The quality of the reported data was high, only 1.3% showing a discrepancy between source data and the database. Overall treatment success was 89%, with no significant differences between hospitals. There were significant differences in clinical practice between the centres, the proportion of patients treated for ulcer disease varying from 36% to 96% (P < 0.001). Doctor compliance with the agreed collaboration varied significantly (P < 0.001). CONCLUSION: Internet collaboration through remote data entry in a common database yields data of high quality without monitoring, and is a powerful and resource economic tool for clinical multicentre trials and quality assurance.
OBJECTIVE: To examine the roles of different types of hospitals in implementation of multicenter Phase II/III trials in Japan, specifically focusing on two dichotomies: public versus private, and academic versus nonacademic. Possible explanation was sought as to why a hospital of one category was more likely to participate in specific types of trials in the Japanese medical environment. METHODS: A database containing attributes of published clinical trials (n = 217) was established from four journals featuring reports of clinical trial results. The preferences of public and academic hospitals for specific types of trials were estimated by applying a linear regression model. The trial compositions of these institutions were also estimated, taking the actual prevalence of trials in 1995 into consideration. RESULTS: Public sector hospitals, which were established for particular policy purposes in the national healthcare system, were more likely to accept trials in some fields (e.g., cardiovascular diseases, anesthesiology, antineoplastics, pediatrics) and of some kinds (e.g., Phase II rather than Phase III trials, trials supervised by the principal investigator in the public sector). Academic hospitals also showed preferences for some types of trials (e.g., cardiovascular diseases, dermatology; Phase II rather than Phase III trials). The analysis focusing on public hospitals suggested that policy purposes were achieved at least in some fields such as antineoplastics and anesthesiology. CONCLUSIONS: Japanese clinical trials were unevenly distributed between public and private sectors, and also between academic and nonacademic sectors. These data provide fundamental information about the clinical research environment for future pharmaceutical research and development strategies and policies.
BACKGROUND/AIMS: Electronic searches on databases for randomised clinical trials and controlled clinical trials do not identify as many trials as handsearches, and trial reporting may be flawed. The aims were to identify all fully reported randomised clinical trials in the Journal of Hepatology and to make a qualitative assessment of the reporting. METHODS: The publications were identified by systematically handsearching the full text of the journal and searching MEDLINE. Central dimensions of trial quality were used to assess the reporting quality of the trials. RESULTS: Randomised clinical trials represented 8.4% of the original articles (171/2028). Ten original articles (0.5%) could not be classified. A search on MEDLINE identified 81.3% of the randomised clinical trials, i.e., 139 out of the 171 identified by the handsearch. A total of 166 randomised clinical trials could be quality assessed. Forty-seven (28.3%) of them reported adequate generation of allocation sequence; 22 (13.3%) adequate allocation concealment; 95 (57.2%) allowed intention-to-treat analysis with only a few losses to follow-up; 50 (30.1%) were double-blind; 33 (19.9%) reported sample-size calculations; 13 trials (7.8%) employed the crossover design; and the median number of subjects per intervention arm in parallel group trials was 19 subjects (interquartile range: 11-31; range: 5-519). The quality of reporting was significantly better in regular issue articles than in supplement articles. CONCLUSIONS: Many important randomised clinical trials are published in the Journal of Hepatology, but there seems to be ample room for improvement of quality of reporting.
This essay explores briefly the approach of the Craniofacial Research Instrumentation Laboratory to the systematic and rigorous investigation of the usual outcome of orthodontic treatment in the practices of experienced clinicians. CRIL's goal is to produce a shareable electronic database of reliable, valid, and representative data on clinical practice as an aid in the production of an improved environment for truly evidence-based orthodontic treatment.
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The emergence of evidence-based health care at an operational level is well underway in the National Health Service, driven on by clinical effectiveness initiatives. Unless evidence-based care is supported by evidence-based policymaking, the environment will not be conducive to effective professional practice. The article describes a methodology that has been developed to meet the needs of the Project for the Enhancement of the Welsh-Protocols for Investment in Health Gain. A detailed description of the background, aims, methods, planning, and supporting documentation of the project is given. The methodological principles are transferable to other policymaking scenarios.
Homeopathy remains one of the most controversial subjects in therapeutics. This article is an attempt to clarify its effectiveness based on recent systematic reviews. Electronic databases were searched for systematic reviews/meta-analysis on the subject. Seventeen articles fulfilled the inclusion/exclusion criteria. Six of them related to re-analyses of one landmark meta-analysis. Collectively they implied that the overall positive result of this meta-analysis is not supported by a critical analysis of the data. Eleven independent systematic reviews were located. Collectively they failed to provide strong evidence in favour of homeopathy. In particular, there was no condition which responds convincingly better to homeopathic treatment than to placebo or other control interventions. Similarly, there was no homeopathic remedy that was demonstrated to yield clinical effects that are convincingly different from placebo. It is concluded that the best clinical evidence for homeopathy available to date does not warrant positive recommendations for its use in clinical practice.
BACKGROUND: Disease registries are powerful tools with the potential to transform the way chronic diseases are managed. To date, however, little work has been done to determine how to optimize the implementation of a chronic disease registry in practice. METHODS: Twenty-nine physicians and their nurse teams in a large community internal medicine practice participated in this 6-month prospective randomized trial in 2000. Teams were assigned to one of three implementation strategies using information from a diabetes registry. Process and outcome measures for diabetes management were analyzed. Process measures included the percentage of patients completing glycosylated hemoglobin (Hgb) testing within 6 months and low-density lipoprotein (LDL) testing within 12 months. Outcome measures included the percentage of patients with a glycosylated Hgb > 9.3% (equivalent to a HgbA1c > 8.0%), the percentage of patients with an LDL cholesterol > 130 mg/dl, and the percentage of patients with controlled blood pressure, defined as < 130/85 millimeters of mercury. Mean change in LDL and glycosylated Hgb values was also measured. RESULTS: Teams randomized to an intervention strategy that included direct letters to patients showed significant improvement across a number of measures. The improvement was most apparent among patients without recent testing or with poorly controlled disease. The two interventions that did not include direct patient letters resulted in limited improvement. DISCUSSION: Disease registries can be used to improve outcomes in the management of diabetes and other chronic diseases. Better outcomes were seen in patients who received letters based on registry-generated data. This strategy should be included as part of a comprehensive chronic disease management plan. Further refinements in the use of registries should result in further incremental improvement.
Comparing the outcome of chemotherapy and bone marrow transplants in the absence of a randomized trial is difficult but necessary for diseases where small numbers of patients make such trials difficult if not impossible. To address this issue for adults with acute lymphoblastic leukemia in first remission, we created an empirical database using two separate datasets, one from the International Bone Marrow Transplant Registry and the other from two multicenter chemotherapy studies. Prior to combining the datasets, a study protocol was developed to define inclusion criteria, outcomes to be compared and statistical methods. The main problems of a non-randomized comparison are biases potentially introduced by differences in baseline composition of the two cohorts and differences in time-to-treatment. The source of the latter bias is different distributions of waiting times between achieving complete remission and receiving post-remission therapy. Several techniques to control these biases were evaluated; each gave qualitatively similar results. These methods can easily be applied to other clinical situations where randomized trials are not available.
UNLABELLED: A wealth of bioinformatics tools and databases has been created over the last decade and most are freely available to the general public. However, these valuable resources live a shadow existence compared to experimental results and methods that are widely published in journals and relatively easily found through publication databases such as PubMed. For the general scientist as well as bioinformaticists, these tools can deliver great value to the design and analysis of biological and medical experiments, but there is no inventory presenting an up-to-date and easily searchable index of all these resources. To remedy this, the BioWareDB search engine has been created. BioWareDB is an extensive and current catalog of software and databases of relevance to researchers in the fields of biology and medicine, and presently consists of 2800 validated entries. AVAILABILITY: BioWareDB is freely available over the Internet at http://www.biowaredb.org/
Large phase III studies have identified limited survival benefits with chemotherapy in high-grade glioma. However, numerous clinical trials have been published previously with smaller patient numbers and no control groups. A small positive effect could be missed this way, resulting in premature rejection of possible beneficial treatment. In order to perform a treatment arm summarizing analysis (TASA), a database was created summarizing treatments published between January 1976 and June 2002. In this database, one record represents a cohort of patients treated in the same way. Various patient cohort characteristics such as median age, and outcome measures including median overall survival times (mOS), were documented. Two-hundred and twenty publications were documented with a total number of 17,213 cases treated in 337 treatment groups. There was a statistically significant relationship between the distribution of histological grades (p<0.001) and the outcome, and a better outcome in younger patient populations (p<0.01). However, the known influence of the median Karnowsky performance scale could not be confirmed in this database. The extent of surgery showed a positive influence only when excluding relapse studies, while the positive effect of radiation was clear in all subgroups (p<0.05). Clinical studies that included nitrosurea in the treatment had a significantly better outcome than those with platinum drugs or without chemotherapy. We conclude that TASA, representing a novel way to perform a meta-analysis, is valid since it confirms the known treatment effects and, therefore, has the potential to provide new insights by combining information from different clinical treatment studies.
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Prostate cancer is one of most common solid tumors in men and poses some of the most difficult problems in clinical research. Although many clinical research hypotheses in this condition have been explored using single center cases series and multi-center clinical trials, the results of these studies have often been equivocal, leaving many questions unanswered. Recently, investigators have utilized large, administrative datasets for prostate cancer research. These databases tend to include large numbers of patients from different geographic regions increasing their generalizability and statistical power. The goal of this report is to review lessons learnt about early prostate cancer using these data sources. In particular, we focus on the application of large, population-based datasets to address issues concerning the natural history of prostate cancer, the impact of race on outcomes in prostate cancer and the effectiveness of various treatments for localized disease. Information gathered from large, administrative databases will be helpful when counseling patients regarding their treatments options for localized prostate cancer and in identifying future directions for prostate cancer research.
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The Irish healthcare system is a mixture of free, state-supported and private medicine. The state-supported General Medical Services (GMS) scheme maintains a large prescription database, which has been used to conduct pharmacoepidemiological studies in Ireland. The dataset is anonymized thus maintaining patient and prescriber confidentiality. Three recent studies using this data are described, two of which outline the effect of regulatory advice and the media on prescribing patterns and one which describes the development of an index of prescribing quality which may be applied to prescription data. The GMS prescription database is presently being complemented by a database for some 0.7 million people who seek reimbursement for prescriptions from individuals or families in excess of 42 Pounds per month which together will have an important role for the continued development of pharmacoepidemiology in Ireland.
OBJECTIVE: Withdrawal of a drug from the market for safety reasons is a serious and sometimes complex decision. The scientific evidence supporting drug withdrawals in the past years is critically appraised. METHODS: With data provided by the Spanish Medicines Agency, all drugs withdrawn from the Spanish market for safety reasons from January 1990 to December 1999 were identified. The adverse drug reactions (ADRs) were classified by the year of withdrawal, by the organ/system affected and by the alleged type of reaction (Rawlins and Thompson classification). A systematic review of the literature was performed. RESULTS: A total of 22 drugs were withdrawn from the market due to safety reasons. In 18 of 22 cases (82%), the evidence supporting the drug withdrawal came from individual case reports, cases series or the combination of data provided by randomised clinical trials and case reports. Hepatic (eight cases) and cardiac (five cases) reactions accounted for 59% (13 of 22) of the total withdrawals. In 10 of 22 (45%) cases, drug withdrawal was clearly due to type-B reactions. Only four withdrawals were based on evidence from observational studies including a comparison group. CONCLUSION: Case reports are the main source of information used to withdraw a drug from the market for safety reasons. It is necessary to improve the quality of evidence supporting the withdrawal process of drugs linked to unexpected and severe ADRs. The use of large databases to perform cohort or nested case-control analyses is the most efficient and reliable method to study type-A class effect ADRs. The implementation of such databases in different countries could increase the quality of the information on ADRs by allowing researchers to conduct efficiently these type of studies.