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Results for “Randomised controlled trial”

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PubMed2000

Does evidence-based medicine exist in the treatment of Menière's disease? A critical review of the last decade of publications.

Debate surrounding the need for evidence-based research in all fields of otolaryngology has recently emerged. A review of English language articles dealing with the treatment of Menière's disease published from 1989 to 1999 was performed. The papers were classified according to article type (observational studies, non-clinical studies, controlled trials, randomised controlled trials) and according to the grade of evidence that was offered. A total of 128 publications were reviewed, of which only three were randomised controlled trials and a further three were well-designed controlled studies without randomization. The majority of papers were non-experimental clinical descriptive studies or case series. Data from this review would suggest that more comprehensive evidence-based studies are required in order to settle areas of confusion surrounding treatment of this relapsing condition

Clinical Trials as Topic↗

PubMed2001

The CRASH trial: the first large-scale, randomised, controlled trial in head injury.

The global epidemic of head injuries is just beginning. Many are caused by road traffic crashes. It is estimated that, by 2020, road traffic crashes will have moved from its present position of ninth to third in the world disease burden ranking, as measured in disability adjusted life years. In developing countries, it will have moved to second. The Corticosteroid Randomisation After Significant Head Injury (CRASH) trial is a large-scale, randomised, controlled trial, among adults with head injury and impaired consciousness, of the effects of a short-term infusion of corticosteroids on death and on neurological disability. Following a successful pilot phase, which included over 1000 randomised participants, the main phase of the trial is now underway. Over the next 5 years, the trial aims to recruit a total of 20,000 patients. Such large numbers will only be possible if hundreds of doctors and nurses can collaborate in emergency departments all over the world. The trial is currently recruiting, and new collaborators are welcome to join the trial (see www.crash.lshtm.ac.uk).

Accidents, Traffic↗

PubMed1998

The practice of antenatal care: comparing four study sites in different parts of the world participating in the WHO Antenatal Care Randomised Controlled Trial.

In the preparation of a randomised controlled trial to evaluate a new programme of antenatal care (ANC) in different parts of the world, we conducted a baseline survey of the ANC procedures in all 53 clinics participating in the trial. There were two components of this survey: (1) description of clinic characteristics and services offered: the staff of each clinic was interviewed and direct observation was made by field supervisors, and (2) the actual use of services by pregnant women attending these clinics: we reviewed a random sample of 2913 clinical histories. The clinical units surveyed were offering most of the activities, screening, laboratory tests and interventions recommended as effective according to the Cochrane Pregnancy and Childbirth Database (PCD), although some of these were not available in some sites. On the other hand, some tests and interventions that are considered not effective according to these criteria are reportedly offered. There was a difference across sites in the availability and offer to low-risk women of vaginal examination, evaluation of pelvic size, dental examination, external version for breech presentation and formal risk score classification, and a notable difference in the type of principal provider of ANC. There was a large variation in the actual use of screening and laboratory tests and interventions that should be offered to all women according to Cochrane PCD criteria: some of these are simply not available in a site; others are available, but only a fraction of women attending the clinics are receiving them. The participating sites all purport to follow the traditional 'Western' schedule for ANC, but in three sites we found that a high percentage of women initiate their ANC after the first trimester, and therefore do not have either the recommended minimum number of visits during pregnancy or the minimum first trimester evaluation. It is concluded that the variability and heterogeneity of ANC services provided in the four study sites are disturbing to the profession and cast doubts on the rationale of routine ANC.

Argentina↗

PubMed1977

Endothelial cell loss and corneal thickness after intracapsular extraction and iris clip lens implantation: a randomised controlled trial (interim report).

Patients in a randomised controlled trial were chosen either to have iris clip lens implantation after intracapsular cataract extraction or intracapsular extraction only. They were assessed in terms of corneal thickness, postoperative epithelial oedema, and endothelial cell counts. All patients had 1 eye submitted to operation, which was carried out by the same surgeon. There was significantly greater increase in corneal thickness (P less than 0.05) on the 5th postoperative day in eyes which had lens implants (23 patients with intracapsular extraction and 19 with implant), but the difference between the 2 groups became insignificant at 1 month (17 patients in each group). Daily corneal thickness measurements and observations of epithelial oedema in a subgroup (20 patients divided equally into 2 groups) showed that postoperatively there was greater and more widespread corneal oedema after implant surgery. When the operated eye was compared with the unoperated eye, endothelial cell loss was significantly greater in those with implants (P less than 0.01) than in those with simple intracapsular extraction.

Aged↗

PubMed1997

The Internet and randomised controlled trials.

Several factors constrain the implementation of Randomised Controlled Trials (RCTs). To obtain large sample sizes a multicentred multinational trial may be necessary or a long sampling period. The larger the trial the larger is the unit cost. To allow larger sample sizes, shorter sampling periods and lower unit costs, new methods are needed. The Internet and in particular the WWW provides such an opportunity. The WWW can provide global access, fast interaction and automation. A prototype Internet Trials Service (ITS) is currently being tested with a real international clinical trial (the Growth Restriction Intervention Trial--GRIT). The ITS is hosted on a Web server. It provides a series of HTML documents that describe the GRIT protocol. Registered centres may enter patients into the GRIT trial via ITS. Java applets are used to collect trial data before returning the study number and randomisation. ITS assumes all trial data will be intercepted by a sniffer. Therefore no information is sent that could specifically identify a patient, this must be sent later by more secure means. ITS assumes that trial centres can be spoofed. To authenticate the patients entered into the trial and the trial data sent, a regular audit report is sent to each centre by secure means for confirmation. By using Java, a full functional data entry system can be developed that runs locally within any Java enabled browser. It can perform data validation locally and also provide a sophisticated user interface.

Child Development↗

PubMed2002

Factors affecting general practitioner involvement in a randomised controlled trial in primary care.

AIMS: To investigate factors associated with patient recruitment by general practitioners (GPs) in a randomised controlled trial in primary care. METHODS: Cross sectional survey of 100 GPs who had agreed to recruit patients for a randomised controlled trial. A postal questionnaire was sent to the 100 GPs to collect information on factors associated with recruitment in the randomised controlled trial. RESULTS: The response rate to the survey was 97%. GPs who reported that practice nurses were involved in the research project were significantly more likely to recruit patients into the trial. Age, sex, membership of an independent practitioner association (IPA), number of half days worked, and the number of GPs working in a practice were not associated with recruitment. CONCLUSIONS: Involvement of practice nurses together with GPs may improve recruitment of patients in randomised controlled trials in primary care in New Zealand.

Adult↗

PubMed2026

EDucation and eXercise for gluteal tendinopathy in an Irish context (EDX-Ireland): findings from the LEAP-Ireland feasibility randomised controlled trial.

OBJECTIVE: To assess feasibility of a randomised controlled trial (RCT) investigating effectiveness of 6 sessions of an EDucation and eXercise intervention delivered over 8 weeks (EDX-Ireland) for gluteal tendinopathy, against usual care. EDX-Ireland was modified from a 14-session EDucation and eXercise intervention (EDX), delivered over 8 weeks, previously evaluated in an Australian RCT. DESIGN: Feasibility parallel RCT. METHODS: Participants were randomly assigned to physiotherapist-led EDX-Ireland or usual care. EDX-Ireland comprised 6 sessions of education, hip abductor strengthening and functional loading over 8 weeks, supported by a home exercise programme. Primary outcomes included success of different recruitment strategies and recruitment/retention rates. Secondary outcomes measured global rating of change and other clinical outcomes. Descriptive statistics (percentage, mean, standard deviations and 95% confidence intervals (CI)) are presented. RESULTS: Of 323 individuals who expressed interest in study participation, 119 completed physical examination screening, and 65 met criteria and consented to participate (recruitment rate 55%). Sixty-five people (89% women; mean age 53.1 ± 9.3 years), were randomised to EDX-Ireland (n = 32) or usual care (n = 33). Eighty-three percent (n = 54) were recruited via social media/community, 3% (n = 2) from general practitioners and 14% (n = 9) from orthopaedic/rheumatology. Retention was 92% (95% CI 82-97%, n = 60) at 8-weeks, and 89% (95% CI 79-96%, n = 58) at 3-months. Feasibility thresholds were met. Effect size estimates indicate that 134 participants would be required for a future RCT. CONCLUSION: Pre-defined recruitment and retention thresholds were met, indicating that a RCT evaluating 6 sessions of physiotherapist-delivered education and exercise against usual care for gluteal tendinopathy is feasible. TRIAL REGISTRATION: Clinicaltrials.gov (NCT05516563).

Humans↗

PubMed2002

A single infusion of intravenous ketamine improves pain relief in patients with critical limb ischaemia: results of a double blind randomised controlled trial.

We report the first double blind randomised controlled trial of regular opioids and an infusion of low dose (0.6 mg/kg) intravenous ketamine compared with opioids and placebo in patients with allodynia, hyperalgesia and hyperpathia secondary to critical limb ischaemia. Thirty-five patients completed the study, 18 received regular opioids plus ketamine, while 17 received regular opioids plus placebo. Using the Brief Pain Inventory, the % pain relief that the patients in the ketamine group attributed to their medication improved significantly from 50% immediately pre-infusion to 65% 24 h post-infusion and 69% 5 days post infusion. Over the same period, the pain relief achieved by the placebo group rose from 58% pre-infusion to 56% 24 h post infusion and then 50% relief 5 days later. This was statistically significant (P<0.05) using both the t-test and the Wilcoxon Rank Sum test. The ketamine group also showed a statistically significant difference 24 h post infusion of the effect of pain on their general activity (P=0.03) and on their enjoyment of life (P=0.004). This study shows that combining a single infusion of low dose ketamine with regular opioid analgesia can result in a significant improvement in pain relief for this patient group.

Aged↗

PubMed1998

Random allocation or allocation at random? Patients' perspectives of participation in a randomised controlled trial.

OBJECTIVES: To explore trial participants' understandings of randomisation. DESIGN: In this exploratory study, which used qualitative research methods, in-depth, semistructured interviews were carried out with 20 participants from the CLasP randomised controlled trial. Interviews were recorded on audio tape and fully transcribed. Data were analysed by comparing transcripts and describing emergent themes, using a grounded theory approach. SETTING: The CLasP study comprises three linked multicentre, pragmatic randomised controlled trials evaluating the effectiveness and cost effectiveness of laser therapy, standard surgery, and conservative management for men with lower urinary tract symptoms or urinary retention, or both, related to benign prostatic disease. SUBJECTS: 20 participants in the CLasP study were interviewed. Sampling was purposeful: men were included from each of the treatment arms, the two major centres, and at different points in the trial. INTERVENTIONS AND OUTCOME MEASURES: Interviews used a checklist of topics to encourage participants to describe their experiences. Narratives concerning randomisation were compared to identify common themes, retaining the context of the discussion to allow detailed interpretation. RESULTS: Most participants recalled and described aspects of randomisation, such as the involvement of chance, comparison, and concealed allocation. Many found the concept of randomisation difficult, however, and developed alternative lay explanations to make sense of their experiences. Inaccurate patient information and lay interpretations of common trial terms caused confusion. CONCLUSIONS: The provision of clear and accurate patient information is important, but this alone will not ensure consistent interpretation of concepts such as randomisation. Patients may need to discuss the purposes of randomisation in order to understand them fully enough to give truly informed consent.

Attitude to Health↗

PubMed2002

Safety education of pedestrians for injury prevention: a systematic review of randomised controlled trials.

OBJECTIVES: To quantify the effectiveness of safety education of pedestrians. DESIGN: Systematic review of randomised controlled trials of safety education programmes for pedestrians of all ages. MAIN OUTCOME MEASURES: Effect of safety education on pedestrians' injuries, behaviour, attitude, and knowledge and on pedestrian-motor vehicle collisions. Quality of trials: methods of randomisation; and numbers lost to follow up. RESULTS: We identified 15 randomised controlled trials of safety education programmes for pedestrians. Fourteen trials targeted children, and one targeted institutionalised adults. None assessed the effect of safety education on the occurrence of pedestrian injury, but six trials assessed its effect on behaviour. The effect of pedestrian education on behaviour varied considerably across studies and outcomes. CONCLUSIONS: Pedestrian safety education can change observed road crossing behaviour, but whether this reduces the risk of pedestrian injury in road traffic crashes is unknown. There is a lack of good evidence of effectiveness of safety education for adult pedestrians, specially elderly people. None of the trials was conducted in low or middle income countries.

Accidents, Traffic↗

PubMed2003

Mammographic screening: evidence from randomised controlled trials.

BACKGROUND: All randomised breast cancer screening trials have shown a reduction in breast cancer mortality in the 'invited for mammography' screening arm compared with the 'control arm' for women aged 50 years and older at randomisation (overall 25%). However, individually published point estimates differ and concern has been raised about methodological quality and outcome measures. Materials and Methods Review of the evidence on breast cancer mortality reduction and discussion of the causes of difference in point estimates in the five Swedish and Canadian trials. A summary of the prerequisites for methodological quality and its available evidence from the trials is given. Data to support breast cancer mortality as a correct outcome measure are presented. RESULTS: There is no reason not to use breast cancer mortality as an outcome measure for trials intended to reduce breast cancer mortality, both from a clinical and a methodological point of view. Everything possible was performed in these trials in order to determine this outcome measure as accurately as possible. The fact that a few of the trials showed a relatively large breast cancer mortality reduction and others far lower reduction rates is irrelevant, if one does not consider the background situation in the region before the trial started, the design of the trial or quality of screening. CONCLUSIONS: There seems no reason to change or halt the current nation-wide population-based screening programmes. Nor is there any justifiable reason for negative reports towards women or professionals.

Adult↗

PubMed1993

Infertility treatment: from cookery to science. The epidemiology of randomised controlled trials.

OBJECTIVES: To review the epidemiology of published randomised controlled trials in infertility treatment over the last 25 years, with special emphasis on the number and quality of trials. DESIGN: Computer literature review by MEDLINE backed up by a manual search of 41 journals. Each trial was classified according to the methodology described and quality criteria. The results were recorded in a computer database. Odds ratios (OR) and confidence intervals (CI) were calculated where the data were sufficient. SUBJECTS: Couples suffering from primary or secondary infertility. The trials studied 33,761 patients overall. SETTING: Institute of Epidemiology and Health Services Research, Leeds. RESULTS: Five hundred and one randomised trials in male and female infertility treatment were identified between 1966 and 1990. Pregnancy was an outcome in 291 (58%) and these were the subject of detailed analysis. Two hundred and twenty-four (77%) and 67 (23%) 'pregnancy trials' were concerned, respectively, with female and male infertility. Four per cent of the trials were preceded by a sample size calculation, and the average sample size was 96 patients (range 5-933); 700 patients per group would be required to demonstrate plausible success rates for most treatments. The method of randomisation was unstated or pseudo-randomised in 206 (71%) of trials where pregnancy was an outcome. Only 29 (5.8%) of studies were multicentre. The method of confirmation of pregnancy was omitted for 70% of papers. Cross-over design was used in 103 (21%) of cases. Meta-analysis is possible for selected topics such as the use of anti-oestrogens in idiopathic oligospermia and unexplained female infertility. Eight cases of double reporting were identified. CONCLUSIONS: Trials using randomised methodology were relatively few in comparison with other branches of medicine, although their use is important in the evaluation of treatment for infertility as treatment-independent pregnancy is common. It was encouraging to note that an exponential increase in the use of this methodology occurred during the last three years, especially in association with assisted conception techniques, and meta-analysis has become possible for selected topics. However, many trials suffer from an unrealistically small sample size, inappropriate use of cross-over design or pseudo-randomisation. The trend towards properly controlled studies should be encouraged but these studies should be of improved quality and organised on a multicentre or even international basis.

Female↗

PubMed2002

Randomised controlled trials in nursing and midwifery: an interview with Maralyn Foureur. Interview by Pamela J. Wood.

Randomised controlled trials are considered to be one of the best research designs for determining effective care in the clinical setting. Relatively few randomised controlled trials, however, have been carried out in nursing or midwifery practice, so few examples of the practical realities of this research methodology are readily accessible. This is the sixth article in a series based on interviews with nursing and midwifery researchers, designed to offer the beginning researcher a first-hand account of the experience of using particular methodologies. This article focuses on the randomised controlled trial as experienced by Maralyn Foureur (RGON, RM, BA, Grad Dip Clin Epidem, PhD) who used this methodology to demonstrate the effectiveness of a continuity of care model in midwifery practice.

Continuity of Patient Care↗

PubMed1993

Developing a register of randomised controlled trials in primary care.

OBJECTIVE: To determine the number, nature, site of publication, and feasibility of identifying randomised controlled trials relevant to primary care. DESIGN: Review of literature using three strategies: approaching journal editors, Medline search, and manual search of individual journals. SETTING: Journals containing publications of studies based in primary care. MAIN OUTCOME MEASURES: The number, site of publication, and subject of trials identified. RESULTS: No journal had a system which enabled identification of all the randomised controlled trials it published. 266 trials relevant to primary care were identified from 110 different journals during 1987-91 by Medline. Of these, only 62 trials were published in primary care journals. Hand searching of seven major primary care research journals showed that between 13% and 38% of the trials had been missed by the Medline search. Of the trials identified, 47 (18%) were concerned with mental disease (including neuroses, tobacco misuse and alcohol misuse) and 43 (16%) were concerned with hypertension. CONCLUSION: Given the diversity of publication sources and topics, this supports the need for a centrally based register of randomised controlled trials that may be relevant to primary care overviews in the future.

Humans↗

PubMed2001

Treatment of irritable bowel syndrome: a review of randomised controlled trials.

Irritable bowel syndrome (IBS) is a common chronic disorder that is associated with significant disability and health care costs. The purpose of this paper is to review and assess published randomised controlled trials examining the clinical effectiveness of interventions for IBS for 1987-1998. A literature search was conducted to identify randomised controlled trials of IBS treatments: 45 studies were identified that described randomised controlled trials and of these, six fulfilled all three criteria used to assess the quality of randomised controlled trials, as described by Jadad and colleagues.(1) These criteria are: adequate description of randomisation, double blinding, and description of withdrawals and dropouts. It is concluded that there are few studies which offer convincing evidence of effectiveness in treating the IBS symptom complex. This review strongly suggests that future work should include well designed trials that: describe the randomisation method; use internationally approved diagnostic criteria; and are double blinded and placebo controlled. Clear well defined outcome measures are necessary. Inclusion of quality of life measures allows comparison between trials in different therapeutic areas. Conducting such studies will help to overcome some of the difficulties identified in this review.

Colonic Diseases, Functional↗

PubMed1994

Participation in breast cancer screening: randomised controlled trials of doctors' letters and of telephone reminders.

The study used a randomised controlled trial to find out whether supporting letters from general practitioners accompanying the invitations from a screening centre affected participation in a population-based breast cancer screening program for women aged 50 to 64. A further randomised controlled trial compared the effect of postal reminders with telephone reminders for women who did not respond to an initial invitation to participate in the program. There were 482 women in the first trial and 641 in the second. Excluding women who were ineligible or could not be contacted, participation in screening was 71 per cent in the group which received letters from their general practitioners compared with 62 per cent in the group which did not receive letters (P = 0.059). In the group that received letters, 56 per cent were screened without a reminder compared with 43 per cent of the group that did not receive letters (P = 0.01). Fewer women who received letters from their general practitioners declined the invitation to be screened (P = 0.048). In the second trial, there was no difference in participation between the group receiving telephone reminders and the group receiving postal reminders. As in breast cancer screening programs in other countries, general practitioner endorsement of invitations increased participation in breast cancer screening. Postal reminders were as effective as telephone reminders in encouraging women who did not respond to an initial invitation to participate in screening.

Breast Neoplasms↗

PubMed1986

Vegetarian diet in mild hypertension: a randomised controlled trial.

In a randomised crossover trial 58 subjects aged 30-64 with mild untreated hypertension were allocated either to a control group eating a typical omnivorous diet or to one of two groups eating an ovolactovegetarian diet for one of two six week periods. A fall in systolic blood pressure of the order of 5 mm Hg occurred during the vegetarian diet periods, with a corresponding rise on resuming a meat diet. The main nutrient changes with the vegetarian diet included an increase in the ratio of polyunsaturated to saturated fats and intake of fibre, calcium, and magnesium and a decrease in the intake of protein and vitamin B12. There were no consistent changes in urinary sodium or potassium excretion or body weight. In untreated subjects with mild hypertension, changing to a vegetarian diet may bring about a worthwhile fall in systolic blood pressure.

Adult↗

PubMed1997

Language bias in randomised controlled trials published in English and German.

BACKGROUND: Some randomised controlled trials (RCTs) done in German-speaking Europe are published in international English-language journals and others in national German-language journals. We assessed whether authors are more likely to report trials with statistically significant results in English than in German. METHODS: We studied pairs of RCT reports, matched for first author and time of publication, with one report published in German and the other in English. Pairs were identified from reports round in a manual search of five leading German-language journals and from reports published by the same authors in English found on Medline. Quality of methods and reporting were assessed with two different scales by two investigators who were unaware of authors' identities, affiliations, and other characteristics of trial reports. Main study endpoints were selected by two investigators who were unaware of trial results. Our main outcome was the number of pairs of studies in which the levels of significance (shown by p values) were discordant. FINDINGS: 62 eligible pairs of reports were identified but 19 (31%) were excluded because they were duplicate publications. A further three pairs (5%) were excluded because no p values were given. The remaining 40 pairs were analysed. Design characteristics and quality features were similar for reports in both languages. Only 35% of German-language articles, compared with 62% of English-language articles, reported significant (p < 0.05) differences in the main endpoint between study and control groups (p = 0.002 by McNemar's test). Logistic regression showed that the only characteristic that predicted publication in an English-language journal was a significant result. The odds ratio for publication of trials with significant results in English was 3.75 (95% CI 1.25-11.3). INTERPRETATION: Authors were more likely to publish RCTs in an English-language journal if the results were statistically significant. English language bias may, therefore, be introduced in reviews and meta-analyses if they include only trials reported in English. The effort of the Cochrane Collaboration to identify as many controlled trials as possible, through the manual search of many medical journals published in different languages will help to reduce such bias.

Bias↗