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Results for “Randomized controlled trials”

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PubMed2004

Interactive video behavioral intervention to reduce adolescent females' STD risk: a randomized controlled trial.

A longitudinal randomized design was used to evaluate the impact of a theoretically based, stand-alone interactive video intervention on 300 urban adolescent girls' (a) knowledge about sexually transmitted diseases (STDs), (b) self-reported sexual risk behavior, and (c) STD acquisition. It was compared to two controls, representing high-quality informational interventions. One used the same content in book form; the other used commercially available brochures. Following randomization, the interventions were administered at baseline, with booster sessions at 1, 3, and 6 months. Self-reports revealed that those assigned to the interactive video were significantly more likely to be abstinent in the first 3 months following initial exposure to the intervention, and experienced fewer condom failures in the following 3 months, compared to controls. Six months after enrollment, participants in the video condition were significantly less likely to report having been diagnosed with an STD. A non-significant trend in data from a clinical PCR assay of Chlamydia trachomatis was consistent with that finding.

Adolescent↗

PubMed1990

A randomized controlled trial of extra-amniotic ethinyloestradiol for cervical ripening in multiparas.

A double-blind randomized controlled trial was carried out to determine if ethinyloestradiol applied extra-amniotically would ripen the unfavourable cervix at term. Twenty five multiparas were given 150 mg ethinyloestradiol gel while 25 multiparas were given gel alone. There was no difference between the ethinyloestradiol and control groups in either mean change of Bishop score or the induction-to-delivery interval.

Adult↗

PubMed1999

A meta-analysis of randomized controlled trials of laparoscopic versus conventional appendectomy.

BACKGROUND: Despite many randomized controlled trials, the merits of laparoscopic appendectomy remain unclear. A meta-analysis may provide insights not evident from any individual studies. DATA SOURCES: Systematic literature search yielded 17 trials (1,962 subjects) of true randomized design with usable statistical data comparing laparoscopic and conventional appendectomy in adults. The effect sizes for operating time, hospitalization, postoperative pain, return to normal activity, wound infection, and intra-abdominal abscess were calculated, using the random effects model to allow for heterogeneity. An estimate of the robustness of all positive findings was also calculated. RESULTS: Modest but statistically significant effect sizes were found for four of the six outcome measures. Laparoscopic appendectomy takes 31% longer to perform, but results in less postoperative pain, faster recovery (by 35%), and lower wound infection rates (by 60%). CONCLUSION: Laparoscopic appendectomy offers significant improvement in postoperative outcomes at the cost of a longer operation.

Adolescent↗

PubMed1999

Issues in surgical randomized controlled trials.

As technology expands and health care resources become more limited, there is increasing pressure on surgeons to evaluate surgical procedures and technology to ensure they are effective. No longer is evidence from case series acceptable, and treatments must be evaluated in randomized controlled trials. The power of the randomized controlled trial is that because of its rigorous design the risk of random or systematic (bias) error is minimized and thus the risk of making an incorrect conclusion about the efficacy of a treatment is minimized. The randomized controlled trial has been widely accepted for evaluating the efficacy of medical treatments but less so for surgical procedures. Many cite methodologic issues related to surgical issues as the reason for this, including concerns related to standardization of the surgical procedure, timing of surgical trials, difficulties with blinding of subjects and investigators, ethics of surgical trials, and patient and surgeon acceptance of surgical trials. These issues are discussed in this paper as are possible strategies to minimize their effect.

Ethics, Medical↗

PubMed2001

Control of bias in randomized controlled trials published in prosthodontic journals.

STATEMENT OF PROBLEM: Randomized controlled trials (RCTs) have become the gold standard for evaluating the effectiveness of treatment interventions. If not properly controlled, bias in the design of trial methodology can affect the validity of the study results. PURPOSE: The purpose of this investigation was to assess the methodological quality of RCTs published in 3 prosthodontic journals over a 10-year period. MATERIAL AND METHODS: Issues of The International Journal of Prosthodontics, The Journal of Prosthetic Dentistry, and The Journal of Prosthodontics published between 1988 and 1997 were searched manually to identify RCTs. Specific inclusion and exclusion criteria were established to identify articles about studies that qualified as RCTs. Two independent reviewers evaluated all qualified RCTs on the basis of how potential sources of bias in the trial methodology were controlled. Three areas-control of bias at entry, control of bias in assessment of outcome, and control of bias after entry-were evaluated with a scheme developed through the Cochrane Collaboration. A score of 1 or 0 was assigned for each of the 3 potential sources of bias, with the maximum quality score for an RCT being 3 (good bias control) and the minimum 0 (poor control). Frequencies were calculated for each dimension of trial methodology and overall quality scores of the RCTs. RESULTS: Sixty-two RCTs were identified from 3631 articles screened. The method of randomization was explicit in only 47% of the RCTs. Forty percent of RCTs incorporated blinding in the assessment of outcome, and 76% accounted for all subjects at the end of the study. Overall quality scores revealed that only 16% of RCTs attempted to control bias in all 3 areas examined. Forty percent were deficient in 1 area, 34% were deficient in 2 areas, and 10% were deficient in all areas examined. CONCLUSION: The quality of RCTs published in prosthodontic journals may be improved by minimizing potential sources of bias and adequately reporting trial methodology.

Dental Research↗

PubMed2004

Early analgesic effects of parecoxib versus ketorolac following laparoscopic sterilization: a randomized controlled trial.

BACKGROUND: The aim of this prospective double blind randomized controlled trial was to compare the effects of ketorolac and parecoxib on early postoperative pain. METHOD: We studied 36 ASA I/II patients who received a standardized general anaesthetic for laparoscopic sterilization. Patients were allocated randomly to receive either parecoxib 40 mg i.v. or ketorolac 30 mg i.v., at induction. After surgery, patients were assessed on awakening and then at 1, 2, and 3 h. Abdominal pain at rest and on inspiration, in addition to nausea and sedation were assessed on a 100 mm visual analogue scale. RESULTS: Of 36 patients, one was excluded from analysis. In the remaining patients, pain scores at rest and on inspiration were significantly lower in patients given ketorolac compared with those given parecoxib. This difference was attributable to the higher pain scores on awakening and at 1 h postoperatively in the parecoxib group compared with the ketorolac group. Despite this initial difference, there was no significant difference between the two groups in the number of patients receiving rescue analgesia. The median (interquartile range) time to consumption of rescue cocodamol of 60 (46-74) min in the parecoxib group was not significantly shorter than that of 100 (70-130) min in the ketorolac group. The amount of cyclizine given, nausea and sedation did not differ significantly between the groups. CONCLUSION: We found that parecoxib 40 mg i.v. given at induction of anaesthesia was less effective than or ketorolac 30 mg i.v., in the first hour after laparoscopic sterilization.

Adult↗

PubMed2003

The combination of calcipotriol and methotrexate compared with methotrexate and vehicle in psoriasis: results of a multicentre placebo-controlled randomized trial.

BACKGROUND: A multicentre, randomized, double-blind, vehicle-controlled, parallel-group study was carried out to study the effect of the addition of calcipotriol ointment to methotrexate (MTX) therapy in patients with psoriasis vulgaris. OBJECTIVES: To investigate whether the addition of calcipotriol to treatment with MTX has an MTX-sparing effect, and whether the combination of treatments is safe. Additionally, to compare the effect of calcipotriol or vehicle on the duration of the relapse-free interval after cessation of MTX. METHODS: Patients on maintenance therapy with MTX with controlled psoriasis were selected. The study was divided into three phases: (i) an MTX-free phase with double-blind treatment with either calcipotriol ointment or vehicle; (ii) an MTX titration phase with open MTX treatment and additional double-blind treatment with either calcipotriol or vehicle until target response; and (iii) follow-up phase: in a group of 97 patients, psoriasis was assessed using the modified psoriasis severity score, patients' assessment and safety parameters were monitored as well. RESULTS: The combined use of calcipotriol with MTX resulted in an MTX-sparing effect of 3.4 mg week-1 (phase (II) and 2.6 mg week-1 (phase I and II taken together), while still maintaining efficacy. Calcipotriol treatment increased the time to relapse of psoriasis following discontinuation of MTX: 113 days vs. 35 days. A decrease in aspartate aminotransferase and alanine aminotransferase was seen during the study of 8% (calcipotriol) and 12% (vehicle). CONCLUSIONS: The combination of calcipotriol and MTX was safe and well tolerated. The combination resulted in lower cumulative dosages of MTX compared with MTX and vehicle. Therefore the risk of side-effects is substantially decreased.

Adult↗

PubMed2003

Intention-to-treat approach to data from randomized controlled trials: a sensitivity analysis.

The intention-to-treat (ITT) approach to randomized controlled trials analyzes data on the basis of treatment assignment, not treatment receipt. Alternative approaches make comparisons according to the treatment received at the end of the trial (as-treated analysis) or using only subjects who did not deviate from the assigned treatment (adherers-only analysis). Using a sensitivity analysis on data for a hypothetical trial, we compare these different analytical approaches in the context of two common protocol deviations: loss to follow-up and switching across treatments. In each case, two rates of deviation are considered: 10% and 30%. The analysis shows that biased estimates of effect may occur when deviation is nonrandom, when a large percentage of participants switch treatments or are lost to follow-up, and when the method of estimating missing values accounts inadequately for the process causing loss to follow-up. In general, ITT analysis attenuates between-group effects. Trialists should use sensitivity analyses on their data and should compare the characteristics of participants who do and those who do not deviate from the trial protocol. The ITT approach is not a remedy for unsound design, and imputation of missing values is not a substitute for complete, good quality data.

Data Interpretation, Statistical↗

PubMed2001

A randomized controlled trial of outpatient commitment in North Carolina.

OBJECTIVE: A randomized controlled trial of outpatient commitment was conducted in North Carolina to provide empirical data on involuntary outpatient commitment and to evaluate its effectiveness in improving outcomes among persons with severe mental illnesses. METHODS: A total of 331 involuntarily hospitalized patients awaiting discharge under outpatient commitment were randomly assigned to be released or to undergo outpatient commitment. Each received case management services and outpatient treatment. Participants in both groups were monitored for one year. After the initial 90-day outpatient commitment order, a patient could receive a renewable 180-day extension. Patients in the control group were immune from outpatient commitment for one year. Information was obtained from self-reports and reports of several informants as well as from outpatient treatment, hospital, and arrest records. RESULTS: In most bivariate analyses, outcomes for the outpatient commitment group and the control group did not differ significantly when the duration of outpatient commitment was not taken into account. However, patients who underwent sustained outpatient commitment and who received relatively intensive outpatient treatment had fewer hospital admissions and fewer days in the hospital, were more likely to adhere to community treatment, and were less likely to be violent or to be victimized. Extended outpatient commitment was also associated with fewer arrests of participants with a combined history of multiple rehospitalizations and previous arrests. The intervention was particularly effective among individuals with psychotic disorders. CONCLUSIONS: Outpatient commitment can improve treatment outcomes when the court order is sustained and combined with relatively intensive community treatment. A court order alone cannot substitute for effective treatment in improving outcomes.

Case Management↗

PubMed2006

Randomized controlled trial of 7-Day vs. 14-Day antibiotics for neonatal sepsis.

There are no evidence-based guidelines available regarding the duration of antibiotics in neonatal septicemia. We compared the effectiveness of a 7-day intravenous antibiotic regimen with the standard 14-day regime in blood-culture-proven sepsis in neonates. This was a controlled, blinded, randomized trial with stratification (for birth weight). Blood-culture-positive septic babies > or =32 weeks and/or > or =1500 g were enrolled if meningitis and other deep-seated focal infections were ruled out. Parental consent was obtained. Randomization to either 7-day or 14-day therapy was done on day 7 of antibiotics if the baby had clinically remitted by day 5. Blood culture was repeated 24 h after antibiotic completion. Subjects were observed in the hospital for at least 72 h, and followed-up for 28 days by weekly visits and telephonic contacts. The primary outcome was treatment failure within 28 days defined as a positive blood culture, or clinical signs accompanied by either positive CRP or adjudicated to be a relapse by an expert committee. A total of 120 babies were eligible, 51 were excluded (no consent: 12; non-remission: 39), and 69 were randomized to receive either a 7-day course (n = 34) or a 14-day course (n = 35) of antibiotics. Baselines variables were comparable in the two groups. Primary outcome assessment could be done in 33 cases in either group. There was a trend to greater treatment failures in the 7-day group compared with 14-day group (5 vs. 1, respectively; P = 0.19). On subgroup analysis of subjects with Staphylococcus aureus infection, those who received 7-day therapy (n = 7) had significantly more treatment failure than 14-day therapy (n = 7) (four and zero, respectively; P = 0.022), whereas on sub-group analysis of babies with non-S. aureus infections, treatment failure rates were identical (3.8% in both groups). On comparing the organisms isolated in the group of subjects which was not randomized by virtue of being symptomatic (n = 39) vs. the group which was randomized (n = 69), it was found that S. aureus infections were significantly commoner in the former group (61.5 vs. 21.3%, respectively; P < 0.001). Neonates > or =32 weeks and/or > or =1500 g with S. aureus sepsis require 14 days of antibiotics. S. aureus infection is also associated with failure to achieve clinical remission by the 5th day of antibiotic therapy. Larger trials are required to confirm whether neonates with non-S. aureus sepsis, whose symptoms remit by 5 days, can be treated with 7 days of antibiotics.

Anti-Bacterial Agents↗

PubMed1997

Pulmonary artery catheterization: a narrative and systematic critique of randomized controlled trials and recommendations for the future.

OBJECTIVE: The purpose of this review is to evaluate the current literature regarding the efficacy of pulmonary artery catheterization, to assess the quality of existing randomized controlled trials and to make recommendations for future studies. DATA SOURCE: A Medline search was conducted of English language studies published between 1970 and 1996 using as search terms "Swan-Ganz catheterization," "pulmonary artery catheterization," and "right heart catheterization." STUDY SELECTION: Randomized controlled trials of pulmonary artery catheterization were selected for review. Sixteen randomized controlled trials were identified. DATA EXTRACTION: The quality of the randomized controlled trials was assessed and a formal meta-analysis was performed. DATA SYNTHESIS: The overall quality score was 40.15 +/- 6.32 out of a possible score of 100. Serious deficiencies were identified including a lack of a priori sample size calculations, unclear definitions of concomitant therapy, inability to blind physicians and patients, and lack of blinded outcome assessments. A random effects model found the relative risk ratio of .808 (95% confidence interval [CI] = .598, 1.091; p = .148). An analysis of potential covariates revealed patients from surgical series treated with pulmonary artery catheter (PAC)-guided therapy had a relative risk ratio of .578 (95% CI = .357, .937; p = .03) compared with control groups. Patients from medical or mixed unit series had a relative risk of 1.043 (95% CI = .784, 1.387; p = NS). CONCLUSION: Existing randomized controlled trials on PAC-guided strategies reveal a modest risk reduction that does reach statistical significance. Risk reduction appears to be greatest in surgical series. Deficiencies of these trials have important implications for the proper design of future trials.

Catheterization, Swan-Ganz↗

PubMed2006

To what extent do real life practice studies differ from randomized controlled trials in lower urinary tract symptoms/benign prostatic hyperplasia?

PURPOSE OF THE REVIEW: To compare the real-life practice studies and randomized controlled trials on benign prostatic hyperplasia in order to understand the applications of the data from the two types of study. RECENT FINDINGS: Until recently, much of the available information on benign prostatic hyperplasia has come from randomized controlled trials conducted by secondary care urologists on selected populations of patients, who are likely to represent the more symptomatic among the cohort of men with lower urinary tract symptoms in the community. The strict inclusion criteria in these trials led to uncertainty about the applicability of the results to community populations. Moreover, as patients in randomized controlled trials are specially recruited, rather than being drawn from a general population of men with lower urinary tract symptoms, the calculations of incidence and prevalence rates may not be possible. In the last few years, there have been a few important real-life practice studies such as the Triumph project, the Quadraet study and the ALF-ONE study, which have provided very useful data regarding the incidence and prevalence of lower urinary tract symptoms/benign prostatic hyperplasia, the incidence of acute urinary retention, the impact of therapy on the risk of surgery related to benign prostatic hyperplasia and the predictors of disease progression during treatment with alpha-blocker. SUMMARY: As the results from randomized controlled trials cannot always be generalized to daily urological practice, it is important to complement them with data made available by the real-life practice studies. In order to do that, the salient features in the methodology of both types of study must be understood.

Humans↗

PubMed2003

Community reactions to the introduction of permethrin-treated bed nets for malaria control during a randomized controlled trial in western Kenya.

Prior to implementation of a randomized controlled trial of insecticide (permethrin)-treated bed nets (ITNs) in western Kenya, ethnographic studies were conducted to understand local perceptions of disease, sleeping patterns, and other factors that might affect use of ITNs. Educational activities took place prior to distribution, but immediately after distribution in Asembo only approximately half of the ITNs were in use. A qualitative study was then conducted to identify the community's perceptions about ITNs and the ITN project. While participants ranked malaria as important and recognized that malaria prevention could be beneficial, they believed ITNs would be only partly effective due to the perception that malaria has multiple causes. Concerns expressed included fear of the insecticide, thought by some to be a toxic family planning aid, the taking of blood during clinical studies, and the mixing up of family ITNs during net re-treatment, which would violate cultural taboos. Attempts were made to allay fears by improved communication on these subjects and modification of the study design.

Attitude to Health↗

PubMed2006

The Trial Protocol Tool: The PRACTIHC software tool that supported the writing of protocols for pragmatic randomized controlled trials.

OBJECTIVE: To develop a tool that would make it easier for researchers, especially those in low- and middle-income countries, to write research protocols for pragmatic randomized controlled trials. STUDY DESIGN AND SETTING: A series of focus groups was held at the inaugural meeting of the Pragmatic RAndomized Controlled Trials in Health Care (PRACTIHC) project in 2001 to develop a desired specification for the Trial Protocol Tool. A working group of five individuals from the PRACTIHC group was formed to develop content for the tool. RESULTS: The Trial Protocol Tool was developed in English and Spanish as a Microsoft Windows HTML help system. A Web-based version is also available. This main body of the tool provides information, advice, and resources about the major headings that should be part of every research protocol. Illustrative examples are used throughout and are taken directly from the tool's protocol library. Additional resources include checklists, programs (e.g., a sample size calculator), and example documents (e.g., patient information leaflets). CONCLUSION: The Trial Protocol Tool packages all the key requirements for the development of a research protocol into one resource. We believe that the use of the tool will help researchers to design effective trials and to write high-quality protocols.

Clinical Protocols↗

PubMedDate not supplied

A randomized control trial of an Ultra-Short zidovudine regimen in the prevention of perinatal HIV transmission in rural Zimbabwe.

OBJECTIVE: To assess the practicality and effectiveness of an Ultra-Short zidovudine regimen for prevention of perinatal HIV transmission in rural Zimbabwe. DESIGN: Double-blinded placebo-controlled randomized clinical trial. SETTING: The Salvation Army Howard Hospital, a district hospital in rural Zimbabwe. SUBJECTS: 222 HIV positive pregnant women presenting for antenatal care prior to 36 weeks were randomized. Twenty nine women were lost to follow up. INTERVENTION: In the Thai regimen, mothers received zidovudine (300 mg po bid) from 36 weeks gestation until labour, and zidovudine (300 mg po q3h) during labour, and the neonates received a placebo. In the Ultra-Short regimen, the mothers received a placebo from 36 weeks to labour, then zidovudine (300 mg po q3h) in labour. The neonates received zidovudine (2 mg/kg po qid) for the first three days of life. MAIN OUTCOME MEASURE: Infant HIV RNA status at six weeks of life. RESULTS: Results were available for 90 infants from the Thai group and 89 infants from the Ultra-Short group. Infant HIV seroconversion rates at six weeks of life were 18.9% (95%CI 10.8 to 27.0) with the Thai regimen, and 15.7% [95% Confidence Interval (CI) 8.1 to 23.4] with the Ultra-Short regimen. The upper bound of seroconversion in the Ultra-Short group was lower than the 25% seroconversion boundary that was specified to show equivalence. CONCLUSIONS: Although the Ultra-Short regimen has equivalent efficacy to the Thai regimen, it also has many practical advantages. Ultra-Short is thus a preferable protocol.

Adult↗

PubMed2004

A national evaluation of school breakfast clubs: evidence from a cluster randomized controlled trial and an observational analysis.

STUDY OBJECTIVE: To measure the health, educational and social impacts of breakfast club provision in schools serving deprived areas across England. DESIGN: A cluster randomized controlled trial and an observational analysis. SETTING: England, the UK. INTERVENTION: funding to establish a school-based breakfast club vs. control (no funding). MAIN RESULTS: Intention to treat analysis showed improved concentration (Trail Making Test Part A) amongst the intervention group at 3 months. Fewer pupils within the intervention group reported having skipped classes within the last month and fewer pupils within the intervention group reported having skipped 1 or more days of school within the last month at 1 year. Observational analysis at 1 year showed a higher proportion of primary-aged breakfast club attendees reported eating fruit for breakfast in comparison to non-attendees. A higher proportion of breakfast club attendees had borderline or abnormal conduct and total difficulties scores (primary-aged pupils) and prosocial score (secondary-aged pupils). CONCLUSIONS: Analyses revealed a mixed picture of benefit and apparent disbenefit. This study illustrated the challenges of evaluating a complex intervention in which the evaluators had less control than is usual in randomized trials over recruitment, eligibility checking and implementation. If the impact of new policy initiatives is to be assessed using the most robust forms of evaluation, social policy needs to be organized so that evaluations can be constructed as experiments. This is likely to prove most difficult where the perceived value of implementing an intervention rapidly is high.

Absenteeism↗

PubMed2003

Methodologic issues in randomized controlled trials of surgical interventions.

A physician's ability to make conclusions about the relative efficacy of interventions based on their clinical experience is limited frequently. Therefore, surgeons commonly use research evidence to guide their clinical practice. The randomized controlled trial is the strongest study design. However, randomization in itself does not guarantee the trial results are valid (free from bias). Understanding the potential impact of various methodologic features of a randomized controlled trial allows a clinician to determine the validity of a trial. We present a guide for evaluating the validity of randomized controlled trials giving special consideration to issues confronted in surgical trials.

Humans↗

PubMedDate not supplied

Flexible sigmoidoscopy as a colorectal cancer screening test in the general population: recruitment phase results of a randomized controlled trial in Lombardia, Italy.

UNLABELLED: A two arm multicentre randomized controlled trial is in progress to evaluate the efficacy of flexible sigmoidoscopy (FS) as a screening test for colorectal cancer in the general population. AIMS: To determine the acceptance rate and feasibility of FS as a colorectal cancer screening test in average-risk asymptomatic volunteers. Average-risk, asymptomatic subjects, aged 55-64 years and assisted by 244 general practitioners (GPs) in Lombardy, Italy, were invited by postal questionnaire (PQ) to enter a study for the prevention of colorectal cancer and asked to indicate their interest in, and willingness to undergo, screening: those responding positively were randomized to the intervention or control arms. GPs were trained in colorectal cancer screening and proposed free FS to their patients randomized to the intervention arm. All sigmoidoscopies were performed by experienced endoscopists. Small polyps were removed at FS. Colonoscopy was indicated for high risk polyps (size more than 5 mm, more than two adenomas, villous histology, severe dysplasia or malignancy). 40,945 subjects were invited. 667 PQs were returned undelivered due to postal failure. 7,892 (19.59%) subjects responded, 2,116 of whom (26.81%) were not included, presenting 1 or more exclusion criteria. We randomized 5,778 volunteers and performed 1,582 sigmoidoscopies out of 2,885 subjects in the intervention arm (54.84% acceptance rate). Although the screening procedure had a good attendance rate in the intervention group, involvement of the people invited was lower than expected. Future FS screening programmes will require a keener focus on recruitment strategies, mainly with participation of GPs.

Colorectal Neoplasms↗