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At least 991 records · Page 55Linked to original sources
PubMed2001

Surgery for persistent otitis media with effusion: generalizability of results from the UK trial (TARGET). Trial of Alternative Regimens in Glue Ear Treatment.

TARGET (Trial of Alternative Regimens in Glue Ear Treatment) is a multicentre UK randomized controlled trial (RCT) comparing bilateral ventilation tubes with and without adjuvant adenoidectomy against non-surgical management in children with bilateral, persistent otitis media with effusion (OME). This paper compares the recruited and randomized children with those that, although eligible, were not included in the RCT for various reasons. This is necessary to identify any potential bias in the overall estimate of treatment effectiveness. At the first visit, 1315 children with OME satisfied the criteria of age (3 years 3 months-6 years 9 months), no previous ear or adenoid surgery, tympanometric evidence of fluid (bilateral B or B + C2) and a hearing loss (conductive loss in both ears of > or =20 dBHL). Of these children, 151 (11%) were not followed up because of overriding concern and 70 (5%) because of parental refusal. Of the 506 children eligible for randomization, because of persistence over 12 weeks of watchful waiting of bilateral OME with the same criteria, 20 (4%) were not randomized because of overriding concern and 75 (15%) because of parental refusal. The distribution of the potential effect modifiers was determined for each group. At the first visit, the only significant differences (P < 0.05), comparing those not recruited because of overriding concern with those recruited, were in respect of sex (61% girls compared with 52% boys) and hearing level (34.6 compared with 33.0 dBHL). At the second visit, the only significant difference involved less frequent upper respiratory tract infections (URTIs) in children whose parents refused to allow randomization (8% compared with 18% had had episodic URTI more often than once every 3 months). It is probable that the findings from the TARGET trial will translate to the entire clinic population in this age group as long as they meet the same audiometric and tympanometric criteria. The differences found can be handled by presentation of disaggregated results.

Adenoidectomy↗
PubMed2002

Relationship between number of proximal contacts and survival of root canal treated teeth.

AIM: The present study tested the hypothesis that having two proximal contacts (PCs) at access is associated with improved survival of root canal treated (RCT) teeth, controlling for important presenting conditions, endodontic variables and restorative factors. METHODOLOGY: A treatment database at the University of Iowa College of Dentistry was used to identify permanent teeth undergoing obturation between 1 July 1985 and 31 December 1987. The list was restricted to teeth of patients with at least one dental visit in each two-year interval from 1985 to 1996, and a simple random sample of 280 patients (n = 400 teeth) was selected. Dental charts, radiographs, and computerized databases were examined to ascertain variables of interest and to verify study inclusion criteria. Kaplan-Meier survival estimates were generated for the 221 teeth satisfying study inclusion criteria. Multivariate Cox models were developed, with standard errors adjusted to account for clustering of teeth within patients. RESULTS: The final Cox model showed that teeth with < or =1 PC at access were lost at a rate three times that of teeth with 2 PCs (hazard ratio = 3.1; 95% confidence interval = 1.9-5.1), controlling for tooth type, presence of radiographic caries at access, and presence of a crown before or after obturation. CONCLUSIONS: Because RCT teeth with two PCs at access experienced substantially better survival than teeth with fewer than two PCs, the influence of PCs on prognosis should be recognized during treatment planning. Future research should employ prospective study designs, capture additional variables, and provide data to support endodontic treatment decisions.

Humans↗
PubMed2003

A systematic review of in vivo retrograde obturation materials.

PURPOSE: The aim of this study was to answer the question: For patients requiring apicoectomy (apicectomy/root-end resection) and retrograde (root-end) obturation (filling), which retrograde obturation (root-end filling) material(s) is/are the most effective, as determined by reduction in periapical radiolucency and elimination of signs and symptoms? MATERIALS AND METHODS: A MEDLINE and a Cochrane search (two specified searches) were conducted to identify randomised (RCT) and nonrandomised controlled clinical trials (CCT), cohort studies (CS) and case-control studies (CCS), published between 1966 and 2002, October week 4, conducted on humans, and published in English, German and French language, relating to retrograde obturation materials following apicoectomy. RESULTS: The MEDLINE and the Cochrane search identified 324 and 21 published articles, respectively. The Cochrane search identified three additional articles to the MEDLINE-search articles. Fourteen studies met the inclusion criteria: two were RCTs, six were CCTs, none was a CS and six were retrospective CCSs. Nine of the 14 studies compared a new retrograde (root-end)-filling material to amalgam, 4 of the 14 studies compared orthograde root canal fillings to retrograde (root-end) amalgam and the fourteenth study compared variations of a resin composite (Retroplast) when used in combination with the bonding agent Gluma (Bayer AG, Gluma 1 and 2). The two RCTs indicated that glass ionomer cement appeared to be equivalent to amalgam. The six CCTs indicated that orthograde filling with gutta-percha and sealer was more effective than amalgam retrograde (root-end)-filling (one trial). Similarly, retrograde (root-end)-filling with (i) composite and Gluma (Bayer AG, Leverkusen, Germany) as bonding agent (one trial), (ii) reinforced zinc oxide eugenol cement (EBA cement) (Stailine, Staident, Middlesex, England; one trial) and (iii) gold leaf (one trial) appeared to be better than amalgam retrograde (root-end)-filling. Finally, gutta-percha retrograde (root-end)-filling appears to be less effective than amalgam (one trial) and Retroplast with ytterbium trifluoride is better than Retroplast with silver, when they are both used with Gluma as bonding agent (one trial). CONCLUSIONS: For the highest level of evidence (RCT) retrograde (root-end)-filling with glass ionomer cement is almost as effective as amalgam. However, there was a significant caveat as there were only two RCTs. At the next highest level of evidence (CCT), and given the additional caveat that there was only one controlled trial for each material, retrograde (root-end) EBA cement, composite with Gluma and gold leaf, as well as orthograde gutta-percha, may be more effective than retrograde (root-end) amalgam filling. In conclusion, these results suggest that additional validating CCTs and RCTs are needed.

Apicoectomy↗
PubMed1997

Advancing the standards of clinical research: the urgent need for new methods and better data.

Some of the weaknesses of the randomized controlled trial (RCT) are pointed out, among them unavoidable biases, the possibility of coming to erroneous conclusions by the 'luck of the draw' and the fact that most such experiments lack a doctor/patient relationship and are of little assistance in clinical decision making. An exaggerated propensity on the part of the medical profession to regard the RCT as the only 'scientific' method for research into therapeutics is noted. The potential advantages of post-marketing surveillance of new interventions in a physician-centred manner are outlined. Such a data base could ultimately be expanded into a data base that records all activity in a given practice. The PACE strategy, employed by haematologists in the north of England, and the sentinel practice primary care research networks used by family doctors contain elements of the system proposed here. However, each possesses disadvantages that limit its applicability to special cases. Random choice of practices for any particular observational study of a new intervention could lend it some of the features of an experiment.

Bias↗
PubMed2002

A community randomized controlled trial to investigate impact of improved STD management and behavioural interventions on HIV incidence in rural Masaka, Uganda: trial design, methods and baseline findings.

OBJECTIVE: To describe study design, methods and baseline findings of a behavioural intervention alone and in combination with improved management of sexually transmitted diseases (STDs) aimed at reducing HIV incidence and other STDs. DESIGN: A three-arm community randomized controlled trial (RCT) of 18 rural communities (approximately 96 000 adults) in SW Uganda. A standardized behavioural intervention was implemented in 12 communities (arms A and B) through community-based education, meetings and information leaflets. Six of these communities in addition received improved STD management through government and private health units (arm B). Arm C communities received routine government health services. Impact assessment was through three questionnaire and serological surveys of 750-1000 adults in each community at 18-24-month intervals. The primary outcome measure was HIV incidence and secondary measures were syphilis and herpes simplex virus type 2 incidence, prevalence of Neisseria gonorrhoea and Chlamydia trachomatis and sexual behaviour changes. RESULTS: Approximately 15 000 adults (72% of eligible population) were enrolled at baseline. HIV baseline prevalence rates were 9-10% in all arms and demographic and behavioural characteristics and STD prevalence were also similar. In intervention communities, there were 391 995 attendance at 81 502 activities (6.1 per target adult), 164 063 leaflets distributed (2.6 per person) and 1 586 270 condoms (16.5 condoms per adult). In the STD communities a total of 12 239 STD cases (65% women) were seen over a 5-year period (7.7 per 100 adults/year). CONCLUSION: This is the first community RCT of its type with a behavioural component. There is fair baseline comparability between study arms and process data suggest that interventions were adequately implemented.

Adolescent↗
PubMed2004

Pharmacotherapy of bipolar II disorder: a critical review of current evidence.

OBJECTIVES: There is much controversy surrounding the diagnosis and treatment of patients with bipolar II disorder (BP II). To address the growing need to find effective treatment strategies for patients with BP II, this article identifies and summarizes available published evidence specific to the pharmacotherapy of BP II. METHODS: Using the keywords, 'bipolar disorder', 'type II' or 'type 2', 'bipolar II', 'hypomania', and 'bipolar spectrum', a search of the databases Medline (via PubMed), the Cochrane Central Register of Controlled Trials (via Ovid), and PsychInfo was conducted for the period January 1994 to January 2003. Articles deemed directly relevant to the treatment of BP II were selected. Studies that included both BP I and II patients were excluded if results for BP II patients were not analyzed and reported separately. RESULTS: Fourteen articles were selected for the review period. There are no double blind, randomized controlled trials (RCT) involving only BP II patients. Most studies investigating the pharmacotherapy of BP II are methodologically limited, having observational or retrospective designs and small samples. For long-term treatment, lamotrigine has the strongest quality of evidence (double blind RCT), while lithium is the best studied. With regard to short-term treatment, there is some limited support for the use of risperidone in hypomania, and for divalproex, fluoxetine and venlafaxine in treating depression. CONCLUSIONS: There is a paucity of sound evidence to help guide clinicians treating BP II patients. Decisions about pharmacotherapy should be made on a case-by-case basis; overall, broad recommendations that are based on available evidence cannot be adequately made. More quality research is needed to delineate effective treatment strategies.

Anticonvulsants↗
PubMed2003

Randomized controlled trials in psychiatry. Part 1: methodology and critical evaluation.

OBJECTIVE: To introduce clinicians to the methodology and critical appraisal of randomized controlled trials (RCTs) in psychiatry. METHOD: The methodology of RCTs in psychiatry is discussed. Using a systematic approach to critical appraisal, a published RCT of treatments for severe depression is examined and evaluated. RESULTS AND CONCLUSIONS: The RCT appraised illustrates certain problematic areas in the methodology of trials in psychiatry. A detailed knowledge of methodology and critique of RCTs is essential in determining whether reported results will influence clinicians' practice.

Cyclohexanols↗
PubMed2002

Botulinum toxin A (BoNT-A) for spasticity in adults. What is the evidence?

There are now many reports from open, uncontrolled studies which suggest that botulinum toxin A (BoNT-A) is valuable in treating spasticity. Evidence of its benefit is also gradually accumulating from randomized controlled trials (RCTs). In this presentation I will discuss the reasons why RCT evidence is being generated, and describe the findings currently available, including preliminary results from as yet unpublished trials. RCT data have been reported for leg and arm spasticity in a variety of diseases, but predominantly in stroke and multiple sclerosis patients. In most RCTs, the effects of BoNT-A are compared with placebo over a single injection cycle. The outcomes are generally positive and support the use of BoNT-A. However, data from RCTs are less convincing than those from open studies for a variety of technical reasons. These especially reflect the difficulties of finding good outcome measures for such a heterogeneous array of patients. There is good evidence that BoNT-A has clinical benefit in treating the mechanical effects of spasticity. In order to further clarify its usefulness, future research should address the strategies of short- and longer-term use of BoNT-A, and the unresolved technical issues of how to get the best out of this new treatment.

Arm↗
PubMedDate not supplied

Gender differences for the predictors of depression in young adults with genital herpes.

Genital herpes is a chronic, stigmatizing, sexually transmitted disease (STD), which is increasing despite efforts to control its spread. Depression is commonly reported among people diagnosed with genital herpes and differences in depression by gender have been reported. Therefore, the purpose of this study was to identify gender differences in the predictors of depression in young adults with genital herpes by secondary analyses of baseline data from a randomized clinical trial (RCT). For the RCT, young adults (193 females, 59 males) with genital herpes were recruited from newspaper advertisements. Participants completed questionnaires measuring illness burden, attitudes toward herpes, stress symptoms, mood states, depression, self-concealment, self-disclosure, substance use, and demographics. Univariate analyses and multiple regression techniques were used to identify variables predictive of depression in this sample. In women, increased anger, decreased vigor, increased confusion, a negative attitude toward herpes, self-concealment, and stress symptoms from genital herpes predicted more depression (R2 = 0.63). In men, increased depression was predicted by increased anger, a negative attitude toward herpes, and a decreased willingness to share personal information with a stranger (R2 = 0.51). Findings suggest that future psychoeducational interventions should address anger as a predictor of depression in this population. Gender-specific interventions need to be developed in order to assist young adults who are living with genital herpes.

Adaptation, Psychological↗
PubMed1999

Implication of evidence-based medicine in prescription guidelines taught to French medical students: current status in the cardiovascular field.

OBJECTIVES: To study how satisfactory the contents of introductory courses in cardiovascular therapeutics, given to medical students in France, are with respect to the concepts of evidence-based medicine. METHODS: Medical school lecturers were asked to provide written course material used as part of medical school courses. Best-available evidence was classified as existent (including two therapeutic subclasses: indicated and contraindicated), and nonexistent. Four scores (from 0 to 10) were given, according to conformity with best-available evidence, and citation of randomized clinical trials (RCT), meta-analyses and therapeutic objectives. RESULTS: Thirty-four written documents were obtained from 43 faculties. Although the score (mean +/- SEM) of conformity with best-available evidence was 5.43 +/- 0.28 for the existent best-available evidence class, the corresponding scores for the citation of RCT, meta-analyses, and therapeutic objectives were, respectively, 1 +/- 0.2, 0.16 +/- 0.07, and 2.7 +/- 0.3. The four scores were highest when the best-available evidence belonged to the indicated class, intermediate when best-available evidence was nonexistent, and lowest for the contraindicated class (P < .05). These scores were significantly higher when the printed material was intended for specialists. CONCLUSION: Despite some limitations, the extent of agreement with the best-available evidence is only moderate. Pathophysiologic reasoning is largely preferred to justify the choice of therapeutics recommended to medical students.

Analysis of Variance↗
PubMed2000

Neoadjuvant radio-chemotherapy in advanced primarilynon-resectable carcinomas of the pancreas.

AIM: To investigate the feasibility of neoadjuvant radio-chemotherapy (RCT) in the treatment of primarily non-resectable pancreas carcinoma the parameters tumour regression, possibility of subsequent resection and tolerability were examined. METHOD: Between 1995 and 1997, 27 patients with locally inoperable (assessed by CT criteria) pancreatic carcinoma received radio-chemotherapy for 5 weeks comprising irradiation (55.8 Gy) and chemotherapy with 5-fluorouracil (5-FU, 1000 mg/m(2)/day; 120 h continuous infusion) and mitomycin C (10 mg/m(2)i.v.-bolus, day 2 and day 30) during the first and fifth week of radiotherapy. Two target volumes were irradiated with fractionated doses of 1.8 Gy up to a total of 50.4 Gy. Radiation was applied once a day five times a week and target volume 1 was irradiated with the same fractionated dose, and an additional boost of 5.4 Gy to make an overall total of 55.8 Gy. RESULTS: Sixteen patients underwent explorative laparotomy, 10 of these were resected (eight Whipple's procedures, two distal pancreatic resections), while six could not be resected due to peritoneal carcinosis (n=3), local irresectability (n=2) and liver cirrhosis (n=1). A further nine patients were found to have unresectable tumours on CT and did not undergo surgery after restaging (five of these patients were staged as < >, three patients had distant metastases and one patient refused surgery). In two patients RCT was abandoned because of progression of disease. CONCLUSIONS: The study protocol described is feasible without significant acute toxicity and when used the resectability rate was improved; the survival rate, however, was not improved. Additional intra-arterial or intraportal application of such drugs as mitomycin C or cisplatin may be necessary.

Adenocarcinoma↗
PubMed2001

Mapping a tumor suppressor gene to chromosome 2p13 in metanephric adenoma by microsatellite allelotyping.

Twelve metanephric adenomas (MA) were studied for allelic imbalance at chromosomal regions known to be involved in the genetics of papillary renal cell tumors (RCT) and Wilms' tumors as well as for loci on chromosome 2p13-21. DNA was isolated from paraffin slides, and allelic status was established by fluorescently-labeled microsatellite markers. No allelic changes were seen in the Wilms' tumor gene region at chromosome 11p13 and in the papillary RCT gene region at chromosome 17q21.32. We delineated a tumor suppressor gene region of approximately 8-centimorgan genetic distance between loci D2S2153 and D2S380 on chromosome 2p13. Allelic changes at this region occurred in 56% of informative cases. Our results provide molecular evidence that MA is a genetic entity, and it can be differentiated from both Wilms' tumor and papillary renal cell adenoma.

Adenoma↗
PubMed2002

A new labeling approach using stable isotopes to study in vivo plasma cholesterol metabolism in humans.

A method to study reverse cholesterol transport in humans was developed using stable isotopes and kinetic analysis. Three normolipidemic subjects received simultaneous intravenous infusions of deuterated leucine and (13)C-acetate for 14 and 8 hours, respectively. Deuterium enrichment was measured in protein-bound leucine in apolipoproteins (apo) B-100 and A-I (using gas chromatography coupled with mass spectrometry [GCMS]) and (13)C-enrichment in unesterified cholesterol and cholesteryl ester (using gas chromatography coupled to isotope ratio mass spectrometry [GC-C-IRMS]) in very-low-density lipoprotein (VLDL), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) during the tracer infusion. Curves were analyzed using multicompartmental analysis. This protocol is suitable to quantify the different processes involved in reverse cholesterol transport (RCT) in humans, including cholesterol esterification, transfer of cholesteryl ester from HDL towards apo B-100-containing lipoproteins, and the contribution of VLDL, LDL, and HDL in the final steps of RCT. In agreement with previous data from kinetic analysis of radiotracer experiments, our results suggest that in fasting normolipidemic subjects the major fraction of cholesteryl ester enters plasma through esterification in HDL (more than 95%). The major fraction of cholesteryl ester disappears through apo B-100-containing lipoproteins (VLDL and LDL) catabolism (mean of 82%) rather than through removal from HDL (mean of 18% with approximately an equal part for apo AI-dependent and independent catabolism, respectively, 7% and 11%). We conclude that this protocol could be applied to study the modulation of these processes by nutrition, diseases, or pharmacologic treatments.

Acetates↗
PubMed2003

The effects of physical exercise on plasma prebeta-1 high-density lipoprotein.

The impact of physical exercise on high-density lipoprotein (HDL) metabolism is recognized as a major mechanism of coronary artery disease (CAD) risk reduction. Prebeta-1 HDL subparticle species play a pivotal role in initiating reverse cholesterol transport (RCT). We examined the effect of acute physical exercise on plasma prebeta-1 HDL levels. Nineteen nonsmoking, healthy men (n = 11) and women (n = 8) not receiving lipid-altering medications completed dietary surveys, and had percent body fat determinations, and fasting blood drawn for measurements of plasma lipids, lipoproteins, apolipoprotein A-I (Apo A-I), and absolute and percent prebeta-1 HDL. Each subject completed cardiopulmonary exercise stress testing to Vo(2max) followed by a 4-km course of run-jogging. Laboratory measurements were repeated from blood drawn immediately after exercise. Mean +/- SD values were determined for age, percent body fat, dietary calories, dietary cholesterol, dietary fat, and plasma lipids, lipoproteins, Apo A-I, and absolute and percent prebeta-1 HDL using 1-way analysis of variance (ANOVA). One-way ANOVA comparisons were made for measurements of plasma lipids, lipoproteins, Apo A-I, and absolute and percent prebeta HDL measurements taken before and after exercise for all subjects combined. Entry characteristics showed the following (mean +/-SD): age, 24 +/- 5.8 years; body mass index (BMI), 22.4 +/- 2.6; percent body fat, 13 +/- 5.7; and Vo(2max), 49.1 +/- 7.9 mL O(2)/kg/min. Exercise significantly increased absolute plasma prebeta HDL (0.10 +/- 0.05 to 0.130 +/- 0.07 microg/mL, P =.039) and decreased plasma HDL-triglycerides (23.3 +/- 10.8 to 12.5 +/- 5.6 mg/dL, P =.012). Our findings indicate that prebeta-1 HDL and HDL-triglyceride metabolism are significant components of the effect of acute exercise on RCT. These findings have important relevance for studies pertaining to exercise-related effects on HDL metabolism as pertains to CAD risk reduction.

Adult↗
PubMed2002

Systematic reviews of specialist epilepsy services.

BACKGROUND: Concern has been expressed over UK epilepsy service standards but the most clinically effective model of care is unknown. OBJECTIVE: To systematically review the current evidence on specialist epilepsy clinics compared to general neurology clinics and specialist epilepsy nurses compared to usual care. METHODS: Medline, Psychlit, Embase, Healthplan, GEARS, BIDS ISI, UKCHHO, international HTA websites, InterTASC databases and The Cochrane Library were searched to September 1999. Any studies comparing specialist epilepsy clinics or nurses to generalist services or usual care, reporting physical health, costs or generic quality-of-life outcomes were included. Two people independently applied inclusion and exclusion criteria and extracted data independently. Randomized controlled trial (RCT) quality was assessed by Jadad score and other studies qualitatively by the likelihood of bias. RESULTS: Findings were one RCT and two other studies on epilepsy clinics and four RCTs and a controlled trial on epilepsy nurses. Data synthesis was inappropriate. Epilepsy clinics showed no evidence of reduced seizure frequency or severity, no quality-of-life information and were more expensive. Epilepsy nurse services showed no evidence of reduced seizure frequency or severity, no effect on quality-of-life but were less expensive. CONCLUSION: There is insufficient evidence to demonstrate the superiority of any particular care model for producing better health outcomes.

Ambulatory Care Facilities↗
PubMed2000

Reasons for accepting or declining to participate in randomized clinical trials for cancer therapy.

This paper reports on the reasons why patients agreed to or declined entry into randomized trials of cancer following discussions conducted by clinicians in both District General and University Hospitals. Two hundred and four patients completed a 16-item questionnaire following the consultation, of these 112 (55%) were women with breast cancer. Overall results showed that 147 (72.1%) patients accepted entry to a randomized clinical trial (RCT). The main reasons nominated for participating in a trial were that 'others will benefit' (23.1%) and 'trust in the doctor' (21.1%). One of the main reasons for declining trial entry was that patients were 'worried about randomization' (19.6%). There was a significantly higher acceptance rate for trials providing active treatment in every arm 98 (80.6%) compared with those trials with a no treatment arm 46 (60.5%), chi2 test P= 0.003. The study outlines a number of factors that appear to influence a patient's decision to accept or decline entry into an RCT of cancer therapy. An important factor is whether or not the trial offers active treatment in all arms of the study. Communication that promotes trust and confidence in the doctor is also a powerful motivating influence.

Adult↗
PubMed2002

[Changing surgical therapy because of clinical studies?].

The randomised controlled clinical trial (RCT) is a powerful instrument to evaluate different therapeutic regimens. In a survey among 115 physicians visiting the 25th annual meeting of the Surgical Society of Berlin and Brandenburg, the RCT was judged to be very important when changes of therapeutic strategies are discussed. 90 % of all participants claimed to use data from RCTs in the clinical routine and 89 % would participate in such a trial. In official (e. g. discussions during coffee breaks at scientific meetings) or non-medical (e. g. non-scientific press or media) sources of information were assessed as irrelevant for decisions regarding therapeutic strategies. However, in contrast to this view laparoscopic cholecystectomy was introduced into clinical practice rapidly because patients informed by external (non-medical) sources preferred to be operated on with the "modern" technique. Clinical trials with a high level of evidence had no relevant influence on the rapid distribution of laparoscopic cholecystectomy. Controversial discussions concerning the extent of lymphadenectomy with gastric resection for carcinoma demonstrate that the value of excellent clinical RCTs is low if their results challenge a stable paradigma of the surgical scientific society. To allow a rational judgement, new surgical technologies should undergo a scientific gradual evaluation in agreement with the principles of evidence based medicine.

Attitude of Health Personnel↗
PubMed1996

Determining sample size and power in clinical trials: the forgotten essential.

Estimation of the sample size is a fundamental but usually ignored requirement of the randomized controlled trial (RCT). Indeed, the publication of small trials without consideration of sample size is worrisome from both medical and ethical viewpoints. Type II errors are common, and readers and investigators may reject worthwhile treatments and interventions. Before embarking on an RCT, the investigator must choose an alpha, a beta, and the rates of outcomes anticipated in both treatment groups. This should reflect the characteristics of the condition and its treatment. If limited sample size or available resources pose a problem, the use of continuous outcome measures, paired before-after measurements, and more common outcome measures can minimize sample size requirements. If these approaches are not satisfactory, then a multicenter trial may be in order.

Clinical Trials as Topic↗