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PubMed1999

Placebo-controlled trials in schizophrenia: are they ethical? Are they necessary?

The current controversy as to the proper role of the placebo control in the evaluation of new treatments for schizophrenia requires an analysis that is sensitive to both ethical and scientific issues. Clinical equipoise, widely regarded as the moral foundation of the randomized controlled trial (RCT), requires the use of best available treatment as the control in RCT. Scientific criticisms of the use of an active control are examined and none present an insuperable barrier to the use of an active control. Indeed, scrutiny of the most recent argument for the use of placebo controls, 'assay sensitivity', suggests that the use of placebo may be the cause of the problem pointed to. Scientific, regulatory, ethical and legal advantages of the use of an active control are described. While the use of a placebo control may be acceptable in carefully defined circumstances, in most cases the use of an active control in schizophrenia research is ethically and scientifically preferable.

Antipsychotic Agents↗
PubMed1999

The treatment of tardive dyskinesia--a systematic review and meta-analysis.

This systematic review aimed to collate randomized controlled trials (RCTs) of various interventions used to treat tardive dyskinesia (TD) and, where appropriate, to combine the data for meta-analysis. Clinical trials were identified by electronic searches, handsearches and contact with principal investigators. Data were extracted independently by two reviewers, for outcomes related to improvement, deterioration, side-effects and drop out rates. Data were pooled using the Mantel-Haenzel Odds Ratio (fixed effect model). For treatments that had significant effects, the number needed to treat (NNT) was calculated. From 296 controlled clinical trials, data were extracted from 47 trials. For most interventions, we could identify no RCT-derived evidence of efficacy. A meta-analysis showed that baclofen, deanol and diazepam were no more effective than a placebo. Single RCTs demonstrated a lack of evidence of any effect for bromocriptine, ceruletide, clonidine, estrogen, gamma linolenic acid, hydergine, lecithin, lithium, progabide, seligiline and tetrahydroisoxazolopyridinol. The meta-analysis found that five interventions were effective: L-dopa, oxypertine, sodium valproate, tiapride and vitamin E; neuroleptic reduction was marginally significant. Data from single RCTs revealed that insulin, alpha methyl dopa and reserpine were more effective than a placebo. There was a significantly increased risk of adverse events associated with baclofen, deanol, L-dopa, oxypertine and reserpine. Meta-analysis of the impact of placebo (n=485) showed that 37.3% of participants showed an improvement. Interpretation of this systematic review requires caution as the individual trials identified tended to have small sample sizes. For many compounds, data from only one trial were available, and where meta-analyses were possible, these were based on a small number of trials. Despite these concerns, the review facilitated the interpretation of the large and diverse range of treatments used for TD. Clinical recommendations for the treatment of TD are made, based on the availability of RCT-derived evidence, the strength of that evidence and the presence of adverse effects.

Double-Blind Method↗
PubMed2003

Non-invasive positive pressure ventilation (NIPPV) in stable patients with chronic obstructive pulmonary disease (COPD).

While non-invasive positive pressure ventilation (NIPPV) has become an accepted management approach for patients with acute hypercapnia, it remains unclear whether it can also be beneficial in stable chronic obstructive pulmonary disease (COPD) patients with chronic respiratory failure. Randomised controlled trials (RCT) with a maximum duration of 3 months showed contradictory effects in blood gasses, dyspnoea, sleep efficiency and health-related quality of life. On the other hand, several uncontrolled trials did show positive results in patients with hypercapnia. Recently, an RCT compared the combination of NIPPV and long-term oxygen treatment (LTOT) with LTOT alone for a period of 2 years in hypercapnic patients. After this period dyspnoea decreased and health-related quality of life improved in the NIPPV compared to the LTOT group. Reasons for the contradictory results in the different trials are probably patient selection, adequacy of ventilation, and length of ventilation. Therefore, at this moment there is no conclusive evidence that NIPPV should be provided routinely to stable patients with COPD. However, a selected group of patients might have clinical benefits from it. Patients who are clearly hypercapnic, who can tolerate an effective level of ventilatory support, and who get enough time to adjust to the ventilator might show clinical benefits even after 3 months. A trial with ventilatory support in this group of patients can be considered.

Carbon Dioxide↗
PubMed1999

How do doctors explain randomised clinical trials to their patients?

As part of a larger study designed to improve doctor-patient communication in randomised clinical trials (RCT), we audiotaped the discussions between doctor and patient in which consent was being obtained for a RCT. This paper reports on 82 discussions conducted by 5 clinical oncologists in both District General and University Hospital outpatient departments. When introducing the subject of trials, uncertainty about treatment decisions was expressed by the doctors in the majority of cases (79, 96.3%). This was most often stated in a general sense (78, 95.1%), but some mentioned personal uncertainty (12, 14.6%), an approach which helps to maintain a trusting doctor-patient relationship. The word randomization was mentioned in 51 (62.2%) consultations, although the process itself was usually described implicitly (78, 95.1%), e.g. by telling the patient that they would be allocated either one or other treatment. Analogies were used in 28 (34.1%) cases to describe the randomisation process. In addition, although treatments and side-effects were described frequently, (68, 82.9%) and (72, 87.8%) respectively, information leaflets about the trials were not given to 23 (28%) patients. The study shows that U.K. clinicians adopt individual methods when providing information and eliciting consent to trials.

Adult↗
PubMed1998

Biopatch--a new concept in antimicrobial dressings for invasive devices.

A randomised controlled trial (RCT) was conducted to assess the reduction in the rate of catheter-related infections associated with the Biopatch dressing (Johnson & Johnson Medical Inc., Arlington, Texas, USA) used for insertion-site management of central venous catheters (CVCs) placed in the intensive care unit. Patients having a CVC placed were randomly assigned to receive either a Biopatch keyhole dressing to the occlusive Opsite IV 3000 (Smith and Nephew Medical Ltd., Hull, UK) (experimental group) or the Opsite IV 3000 alone (control group). There was a very low colonisation rate of CVC tip and skin exit-site swabs in both the experimental group (6 of 17) and the control group (5 of 16). No statistical difference was found between the two groups with regard to CVC or exit-site colonisation. A calculated sample size of 11,000 would be required to statistically demonstrate a 10 per cent reduction in CVC infection rate using the new Biopatch dressing. A much larger RCT would be required to demonstrate the efficacy of this new device.

Adult↗
PubMed1995

The randomized clinical trial as a powerful means for understanding treatment efficacy.

The comparison of technologies, ie, alternative ways to accomplish the same aim, is inherently difficult. In orthodontics, technology covers a wide spectrum of areas: variations in treatment approach, appliances, wires, diagnostic procedures, and patient management techniques. Clinical trial methodology has been developed to minimize the effect of bias and to provide more objective answers to questions of comparative efficacy and benefits of particular treatments or procedures. The randomized controlled clinical trial (RCT) is now generally considered the strongest research design for the comparison of treatments. This report reviews four issues that should be addressed in planning an RCT: defining the study cohort, selecting the treatment allocation technique, estimating sample size, and performing the trial.

Data Interpretation, Statistical↗
PubMed2004

Randomization in controlled clinical trials: why the flip of a coin is so important.

The randomized controlled trial (RCT) is considered the highest level of medical evidence. In this brief overview, we discuss several key principles of the RCT. First, balance is paramount. Comparison groups must have similar proportions of participants with "important" prognostic and confounding factors. Randomization may or may not achieve this balance; if it does not, statistical adjustments should be used. Second, a statistical analysis should emphasize comparability and not mask dissimilarity. If the trial was indeed randomized, certain analysis techniques, such as an intention to treat analysis, should always be presented. Third, additional bias-reducing techniques, such as concealing treatment assignments from treating physicians and participants (i.e., masking) and using clearly defined exclusion and inclusion criteria, should be used wherever possible.

Humans↗
PubMedDate not supplied

[Definition of prostatic contours using tomodensitometric slices: study of differences among radiotherapists and between examinations].

Accuracy of conformal treatment planning for prostatic radiotherapy is based on the contours of target volumes (prostate +/- seminal vesicles) and normal tissues (rectum and bladder), drawn on CT (computed tomography) images by radiation oncologists. The interpretation of a given CT image can be different from one radiation oncologist to another, and may change in time with the state of filling of the bladder and of the rectum during the treatment. In order to quantify these variations, 12 patients treated with conformal radiotherapy for prostate carcinoma (pelvis 40 Gy/20 sessions + prostate 30 Gy/15 sessions) had two series of CT at one month intervals. Contouring of prostate, rectum and bladder were performed independently on each CT by two radiation oncologists. The first CT scan (planning CT) and the first series of contours (planning contours) were used for treatment planning. The contours of the second scan were compared to the planning contours after image fusion based on manual superimposition of bony anatomy of the two sets of CT images. Coherence ratio were defined to measure discrepancies in prostate volumes between radiation oncologists (RCE) and between scans (RCT). The mean RCE was 38 +/- 7% (1 standard deviation). Those discrepancies were primarily located at the prostate apex and at the interface between bladder and prostate and between rectum and prostate. The mean RCT was 42 +/- 8% (1 sigma). Those discrepancies were due to the prostate motion related to the state of filling of the rectum and bladder. For bladder and rectal walls, less important differences were observed between the two radiation oncologists for the same CT (4.5% for rectal volume receiving 65 Gy or more, 3% for bladder volume receiving 65 Gy or more). However, important differences in bladder and rectal volumes receiving 65 Gy or more (16% and 7% respectively) were noted for the same patient from a CT to another due to the variation in bladder or rectal filling. New techniques for planning CT acquisition are needed to decrease the discrepancies due to contouring. The treatment must, as far as possible, be delivered with an empty bladder and rectum in order to ensure a good reproduction of the initially planned treatment.

Anthropometry↗
PubMed2001

Evaluating informatics applications--some alternative approaches: theory, social interactionism, and call for methodological pluralism.

A review of evaluation literature concerning CDSSs indicates that randomized controlled clinical trials (RCTs) are the 'gold standard' for evaluation. While this approach is excellent for studying system or clinical performance, it is not well suited to answering questions concerning whether systems will be used or how they will be used. Because lack of use of CDSS has been of concern for some years, other evaluation research designs are needed to address those issues. This paper critiques RCT and experimental evaluation approaches and presents alternative approaches to evaluation that address questions outside the scope of the usual RCT and experimental designs. A wide range of literature is summarized to illustrate the value of evaluations that take into account social, organizational, professional, and other contextual considerations. Many of these studies go beyond the usual measures of systems performance or physicians' behavior by focusing on 'fit' of the system with other aspects of professional and organizational life. Because there is little explicit theory that informs many evaluations, the paper then reviews CDSS evaluations informed by social science theories. Lastly, it proposes a theoretical social science base of social interactionism. An example of such an approach is given. It involves a CDSS in psychiatry and is based on Kaplan's 4Cs, which focus on communication, control, care, and context. Although the example is a CDSS, the evaluation approach also is useful for clinical guideline implementation and other medical informatics applications. Similarly, although the discussion is about social interactionism, the more important point is the need to broaden evaluation through a variety of methods and approaches that investigate social, cultural, organizational, cognitive, and other contextual concerns. Methodological pluralism and a variety of research questions can increase understanding of many influences concerning informatics applications development and deployment.

Attitude↗
PubMed2004

Community level Australian Football: a profile of injuries.

Identification of injuries and their risk factors is required in order to develop risk controls within the context of sports injury prevention. The Australian Football Injury Prevention Project (AFIPP) was a randomised controlled trial (RCT) examining the effects of protective equipment on injury rates in Australian Rules Football. The aim of this paper is to describe the general injury profile of community level Australian Football players over one season, as recorded during this RCT. Players were recruited from the largest community football league in Victoria, Australia, during the 2001 playing season. A total of 301 players participated (64% response rate) and all injuries occurring during training and games were recorded. The overall injury incidence rate was 12.1/1000 player hours. Bruises/soft tissue injuries made up more than a quarter of all injuries (28%) and the leg (lower leg, ankle, thigh/hamstring and knee) was the most commonly injured body region. Most injuries occurred at the beginning of the season (April-May, 53% of injuries), during competition (77%) and through body contact (49.9%). Midfielders (OR = 3.39, 95% CI: 1.13, 10.14) and players aged at least 25 years (OR = 2.15, 95% CI: 1.06, 4.34) were significantly more likely to experience an injury than other playing positions and younger players. Although the injury rate in this study was lower than that in previous studies, the results are consistent with the finding that injuries tend to occur earlier in the season and more commonly during competition. Injury prevention efforts should be particularly targeted at midfielders and older players.

Adolescent↗
PubMed2001

Expression of the prostaglandin E(2) (PGE(2)) receptor subtype EP(4) and its regulation by PGE(2) in osteoblastic cell lines and adult rat bone tissue.

Prostaglandins E (especially PGE(2)) stimulate bone formation and increase bone mass in several species including man. The mechanism for this effect, the target cells, and the receptors involved are not known. Specific cell-surface receptors for PGE(2) (EP(1-4)) have been cloned and characterized. EP(4) was reported to be the major receptor in embryonic and neonatal bone tissue in mice, especially in preosteoblasts; however, no data are available regarding its expression in adult bone. This study examines the expression of EP(4) in bone tissue of young adult rats, in which PGE(2) is markedly anabolic, and in various osteoblastic cell lines. Using northern blot analysis, we found that osteoblastic cell lines RCT-1, RCT-3, TRAB-11, and RP-1, primary osteoblastic cells harvested from fetal rat calvaria, as well as tibiae and calvariae of 5-week-old rats express 3.8 kb EP(4) messenger RNA (mRNA). Treatment of periosteal cells (RP-1) in vitro with 10(-6) mol/L PGE(2) increased the levels of both EP(4) mRNA and EP(4) protein, peaking at 1-2 h. Similarly, systemic administration of an anabolic dose of PGE(2) (3-6 mg/kg) to young adult rats upregulated the expression of EP(4) in the tibia and calvaria, also peaking at 1-2 h. Using in situ hybridization, we found increased expression of EP(4) in bone marrow cells of the tibial metaphysis in response to systemic PGE(2) treatment. The preosteoblastic nature of these EP(4)-expressing cells was suggested by the fact that dexamethasone-treated bone marrow stromal cells in culture express EP(4) mRNA, which is upregulated by PGE(2). Northern blot analysis failed to detect both basal and PGE(2)-induced EP(2) mRNA in the bone samples or cell lines tested. Taken together, these data implicate EP(4) as the major cyclic AMP-related PGE(2) receptor subtype expressed in bone tissue and osteoblastic cells and indicate that this receptor is upregulated by its ligand, PGE(2).

Animals↗
PubMed2006

Influence of ethanol on the rennet-induced coagulation of milk.

The influence of ethanol on the rennet-induced coagulation of milk was studied to investigate potential synergistic effects of these two mechanisms of destabilisation on the casein micelles. Addition of 5% (v/v) ethanol reduced the rennet coagulation time (RCT) of milk, whereas higher levels of ethanol (10-20%, v/v) progressively increased RCT. The temperature at which milk was coagulable by rennet decreased with increasing ethanol content of the milk. The primary stage of rennet coagulation, i.e., the enzymatic hydrolysis of kappa-casein, was progressively slowed with increasing ethanol content (5-20%, v/v), possibly due to ethanol-induced conformational changes in the enzyme molecule. The secondary stage of rennet coagulation, i.e., the aggregation of kappa-casein-depleted micelles, was enhanced in the presence of 5-15% ethanol, the effect being largest at 5% ethanol. Enhanced aggregation of micelles is probably due to an ethanol-induced decrease in inter-micellar steric repulsion. These results indicate an interrelationship between the effects of ethanol and chymosin on the casein micelles in milk, which may have interesting implications for properties of dairy products.

Animals↗
PubMed1998

A qualitative assessment of randomized controlled trials in otolaryngology.

In 1996 the CONSORT statement made recommendations on the strict reporting of randomized controlled trials (RCT). This will facilitate the future assessment of such trials and will highlight those trials that have been performed suboptimally and whose results may be biased. We have devised a scoring system, based on CONSORT, to assess RCT quality and by reading each original paper in full we have now assessed the quality of trials published from 1966 to 1995. The mean score for trials identified was 7.3 out of a maximum 12 points. No one journal was significantly better than the others. Trials in rhinology are reported better than head and neck oncology trials (mean scores 7.6 and 6.5 respectively). The past 30 years has not seen an improvement in the quality of the trials. The reporting of RCTs in the ENT literature is poor. CONSORT guidelines now exist and trialists are encouraged to adopt them when conducting future clinical trials.

Head and Neck Neoplasms↗
PubMed2006

Pre-morbid IQ and response to routine outcome assessment.

BACKGROUND: Routine use of standardized outcome measures within adult mental health services is compulsory in many countries, but not common in clinical practice. As well as political and professional factors, one reason may be that there is little empirical evidence of benefit for patients. It is therefore important to identify predictors of response. Pre-morbid intellectual functioning has predicted response to other interventions. This paper tests the hypothesis that pre-morbid IQ impacts on the effectiveness of routine assessment and feedback of outcome measures. METHOD: The Feedback of Outcomes to Users and Staff (FOCUS) single-blind randomized controlled trial (RCT) investigated routine completion and feedback of outcome measures for 160 (101 intervention, 59 control) adult mental health service patients in Croydon, South London (International Standard RCT Number 16971059). RESULTS: Patients in the top quarter (pre-morbid IQ>110) differentially improved in patient-rated unmet need (adjusted difference 3.4, 95% CI 0.8 to 5.9, p=0.012) and in the top half (pre-morbid IQ>99) in quality of life (adjusted difference -0.6, 95% CI -1.1 to -0.1, p=0.02). The top quarter result remained when controlling for the influence of baseline (p=0.004) and baseline plus follow-up variables (p=0.047). CONCLUSIONS: Feedback of routine outcome measures may improve outcome for patients with higher pre-morbid IQ. There is a need to understand more how routine outcome information is used by staff and patients to inform care. If the goal of routine use of outcome measures is to benefit patients directly, then targeted policies are required.

Adolescent↗
PubMed1998

Trials and tribulations. Emerging issues in designing economic evaluations alongside clinical trials.

Decisions relating to designing and implementing economic evaluations alongside clinical trials are dependent on a number of issues initial consideration should focus on whether an economic evaluation is appropriate, whether a randomized controlled trial (RCT) is a suitable vehicle, and whether the design of the specific RCT is appropriate for integration of economic evaluation. If an economic evaluation is appropriate, decisions are required on how economic data are to be collected and analyzed. This paper discusses these and other issues and, where appropriate, provides recommendations for future studies.

Costs and Cost Analysis↗
PubMed2000

Evaluation of randomized controlled trials on complementary and alternative medicine.

OBJECTIVES: Use of complementary and alternative medicine (CAM) is growing in all Western countries. The goal of this study was to evaluate quality of randomized controlled trials (RCTs) of CAM interventions for specific diagnoses to inform clinical decision making. METHODS: MEDLINE and related databases were searched for CAM RCTs. Visual review was done of bibliographies, meta-analyses, and CAM journals. Inclusion criteria for review and scoring were blinded RCT, specified diagnosis and intervention, complete study published between January 1, 1966 and July 31, 1998 in an English-language, peer-reviewed journal. Two reviewers independently scored each study. RESULTS: More than 5,000 trials were found, but only 258 met all study inclusion criteria. The main cause for rejection (> 90%) was that the study was not an RCT or had no blinding. Mean score across 95 diagnosis/intervention categories was 44.7 (S.D. +/- 14.3) on a 100-point scale. Ordinary least-squares regression found date of publication, biostatistician as author or consultant, published in one of five widely read English-language medical journals and diagnosis/intervention category of hypertension/relaxation as significant predictors of higher scores. CONCLUSIONS: The overall quality of evidence for CAM RCTs is poor but improving slowly over time, about the same as that of biomedicine. Thus, most services are provided without good evidence of benefit.

Complementary Therapies↗
PubMed2003

Does clinical trial subject selection restrict the ability to generalize use and cost of health services to "real life" subjects?

OBJECTIVES: To explore one aspect of the external validity of the randomized controlled trial (RCT), specifically how being selected for inclusion in a trial and having participated has influenced the use and cost of asthma-related health services. METHODS: Services used by asthmatic users of inhaled corticosteroids (iCSTs) having previously participated in an RCT (TS, n = 46) were compared with individuals who had never participated (NS, n = 51). RESULTS: TS were more likely to use higher (> or = 400 microg) daily doses of iCSTs than NS (OR, 3.3; 95% Cl, 1.1-8.3) but less likely to visit emergency departments (OR, 0.3; 95% Cl, 0.1-0.7). Total asthma-related costs did not differ significantly. CONCLUSIONS: Subject differences may impede generalizing from RCTs to real life.

Adrenal Cortex Hormones↗
PubMed2003

Predicting survival in cost-effectiveness analyses based on clinical trials.

This study deals with the question of how to model health effects after the cessation of a randomized controlled trial (RCT). By using clinical trial data on severe congestive heart failure patients, we illustrate how survival beyond the cessation of an RCT can be predicted based on parametric survival models. In the analysis, we compare predicted survival and the resulting incremental cost-effectiveness ratio (ICER) of different survival models with actual survival/ICER. Our main finding is that the results are sensitive to the choice of survival model and that an extensive sensitivity analysis in the CE analysis is required.

Angiotensin-Converting Enzyme Inhibitors↗