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Results for “Randomized controlled trials”

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PubMed1999

Antipsychotic medication for challenging behaviour in people with intellectual disability: a systematic review of randomized controlled trials.

A study was performed to determine the effectiveness of antipsychotic medication for people with intellectual disability (ID) and challenging behaviour. Randomized controlled trials comparing antipsychotic medication to placebo in people with ID and challenging behaviour were identified by electronic searching and hand-searching. Reviewers independently evaluated and analysed data on an intention-to-treat basis. Only three randomized controlled trials could be included in the analyses. These trials provided no evidence as to whether antipsychotic medication does or does not help adults with ID and challenging behaviour. There is limited data on this important issue and good quality research is urgently needed.

Antipsychotic Agents↗

PubMed1976

A randomized controlled trial of vitamin C in the prevention and amelioration of the common cold.

A randomized controlled trial of the effect of 1 g ascorbic acid per day in the prevention of the common cold was conducted on 688 adult women. There is evidence of a small reduction by vitamin C in the mean number of chest colds, but no evidence of any effect on simple colds. The existence of a subgroup of vulnerable women in the community who benefit from vitamin C was considered but further examination of the data gives no support to this conclusion.

Adult↗

PubMed2006

Systematic evaluation of the quality of randomized controlled trials in diabetes.

OBJECTIVE: We sought to systematically ascertain the quality of randomized controlled trials (RCTs) in diabetes. RESEARCH DESIGN AND METHODS: We identified the 10 most recently published trials as of 31 October 2003 in each of six general medical, five diabetes, and five metabolism and nutrition journals and further enriched our sample with 10 additional RCTs from each of five journals that published the most eligible RCTs in a year. We explored the association between trial characteristics and reporting quality using univariate analyses and a preplanned multivariate regression model. RESULTS: After excluding redundant reports of included trials and one trial that measured outcomes on the health system and not on patients, we included 199 RCTs: 119 assessed physiological and other laboratory outcomes, 42 assessed patient-important outcomes (e.g., morbidity and mortality, quality of life), and 38 assessed surrogate outcomes (e.g., disease progression or regression, HbA(1c), cholesterol). Fifty-three percent were of low methodological quality, as were one-third (36-40%) of trials reporting patient-important or surrogate outcomes and two-thirds (64%) of laboratory investigations. Independent predictors of low quality were nonprofit funding source (odds ratio 3.1 [95% CI 1.5-6.2]), measure of physiological and laboratory outcomes (2.3 [1.2-4.4]), and cross-over design (2.3 [1.1-4.8]), all characteristics of laboratory clinical investigations. CONCLUSIONS: There is ample room for improving the quality of diabetes trials. To enhance the practice of evidence-based diabetes care, trialists need to pay closer attention to the rigorous implementation and reporting of important methodological safeguards against bias in randomized trials.

Diabetes Mellitus↗

PubMed1995

The use of topical 4% lidocaine in spheno-palatine ganglion blocks for the treatment of chronic muscle pain syndromes: a randomized, controlled trial.

To assess the efficacy of 4% topical lidocaine in spheno-palatine blocks, a randomized controlled trial was carried out on patients with chronic muscle pain syndromes. Sixty-one patients (42 with fibromyalgia (FM) and 19 with myofascial pain syndrome (MPS)) completed the trial. Outcome measures included pain intensity, a daily pain diary, headache frequency, sensitivity to pressure using a dolorimeter, anxiety, depression, and sleep quality. Patients were randomized to receive either 4% lidocaine or sterile water (placebo) 6 times over a 3-week period. Both subjects and investigators were blind to treatment allocation. The results showed that 4% lidocaine had no superiority over placebo in any of the outcome measures. Twenty-one subjects (35%) showed a decrease in pain which was greater than 30% of their baseline value. Of these 21 subjects, 10 received lidocaine and 11 received placebo. These data suggest that, in this population, 4% lidocaine is no better than placebo in the treatment of chronic muscle pain.

Administration, Topical↗

PubMed2001

Patterns of patient enrollment in randomized controlled trials.

We aimed to describe enrollment patterns in a large cohort of randomized controlled trials (RCTs) and evaluate whether early recruitment predicts the ability of RCTs to reach their target enrollment. We considered all 77 efficacy RCTs initiated by the AIDS Clinical Trials Group between 1986 and 1996 (28,992 patients enrolled until November 1999). Thirteen RCTs (17%) failed to reach half their target recruitment. Enrollment trajectories showed that the initial rate of accrual determined the subsequent rates of enrollment. The target sample size was attained by 7/8, 11/14, 15/35 and 4/20 of trials with very rapid, rapid, moderate and slow enrollment during the first 3 months, respectively (P < 0.001). Enrollment during the first month or two strongly correlated with subsequent accrual (P < 0.001). The patient pool, the eligibility criteria, the attractiveness of a trial and adequacy of the network of clinical sites may influence RCT enrollment. Early enrollment offers strong evidence on the feasibility of a trial and is indicative of its future pace of recruitment.

Acquired Immunodeficiency Syndrome↗

PubMed2005

Effectiveness of a home-based balance-training program in reducing sports-related injuries among healthy adolescents: a cluster randomized controlled trial.

BACKGROUND: Sport is the leading cause of injury requiring medical attention among adolescents. We studied the effectiveness of a home-based balance-training program using a wobble board in improving static and dynamic balance and reducing sports-related injuries among healthy adolescents. METHODS: In this cluster randomized controlled trial, we randomly selected 10 of 15 high schools in Calgary to participate in the fall of 2001. We then recruited students from physical education classes and randomly assigned them, by school, to either the intervention (n = 66) or the control (n = 61) group. Students in the intervention group participated in a daily 6-week and then a weekly 6-month home-based balance-training program using a wobble board. Students at the control schools received testing only. The primary outcome measures were timed static and dynamic balance, 20-m shuttle run and vertical jump, which were measured at baseline and biweekly for 6 weeks. Self-reported injury data were collected over the 6-month follow-up period. RESULTS: At 6 weeks, improvements in static and dynamic balance were observed in the intervention group but not in the control group (difference in static balance 20.7 seconds, 95% confidence interval [CI] 10.8 to 30.6 seconds; difference in dynamic balance 2.3 seconds, 95% CI 0.7 to 4.0 seconds). There was evidence of a protective effect of balance training in over 6 months (relative risk of injury 0.2, 95% CI 0.05 to 0.88). The number needed to treat to avoid 1 injury over 6 months was 8 (95% CI 4 to 35). INTERPRETATION: Balance training using a wobble board is effective in improving static and dynamic balance and reducing sports-related injuries among healthy adolescents.

Adolescent↗

PubMed2004

The emotional impact of amblyopia treatment in preschool children: randomized controlled trial.

PURPOSE: To investigate the emotional status of children undergoing active treatment for amblyopia. DESIGN: Postal survey, in the context of a prospective, multicenter, randomized controlled trial. PARTICIPANTS: Parents of 177 children with a unilateral visual impairment referred from preschool vision screening. The children had been recruited to a randomized controlled trial of treatment for unilateral visual impairment and randomly assigned to receive either glasses with or without patches, glasses alone, or treatment deferred for 1 year. METHODS: A self-completion questionnaire, including a psychometric behavioral scale, was sent to the parents of all children recruited to the trial at age 4 years, to 66 whose deferred treatment began at age 5 years, and finally to 151 remaining in the trial at the end of follow-up. MAIN OUTCOME MEASURES: Mean scores per treatment group on the Revised Rutter Parent Scale for Preschool Children. Comparison of parent responses to questions assessing the child's general well-being and difficulties associated with treatment. RESULTS: Completed questionnaires were returned for 144 of 177 (81%) children at a mean age (standard deviation) of 48 months (5.0), for 45 of 66 (68%) at a mean age of 61 months (5.8), and for 78 of 151 (52%) at a mean age of 67 months (5.0). Most parents reported having difficulty with patching their child regardless of age (77% at age 4 years and 73% at age 5 years), with fewer reporting difficulties with glasses alone (42% and 53%, respectively). Children were significantly more upset by patching than by glasses only (chi-square test, P = 0.03 for age 4 years and P = 0.01 for age 5 years), as were the parents of 4-year-olds (chi-square test, P = 0.01). Most parents thought their children were happy, cooperative, and good tempered, and behavioral scores did not differ between treatment groups. CONCLUSIONS: Treatment for unilateral visual impairment is not easy to implement and is commonly associated with some degree of distress. Despite this, no impact on the child's global well-being or behavior was seen either during or after the treatment period.

Affective Symptoms↗

PubMed2000

Laparoscopic compared with open methods of groin hernia repair: systematic review of randomized controlled trials.

BACKGROUND: The place of laparoscopic groin hernia repair remains controversial. Individual randomized controlled trials alone have not provided statistically reliable results when considering recurrence, potentially serious complications and chronic pain. METHODS: A rigorous systematic review was performed of published data from all relevant randomized or quasi-randomized trials. Electronic databases were searched and members of the EU Hernia Trialists Collaboration consulted to identify trials. Prespecified data items were extracted from reports and, where possible, quantitative meta-analysis was performed. RESULTS: Thirty-four published reports of eligible trials were included, involving 6804 participants. Sample sizes ranged from 20 to 1051, with follow-up from 6 weeks to 36 months. Duration of operation was longer in the laparoscopic groups (P < 0.001, Sign test). Operative complications were uncommon for both methods, but visceral and vascular injuries were more frequent in the laparoscopic group (4.7 per 1000 versus 1. 1 per 1000). Postoperative pain was less among laparoscopic groups (P = 0.08). Length of hospital stay did not differ significantly between groups (P = 0.50), but return to usual activity was earlier for laparoscopic groups (P < 0.001). Chronic pain and numbness were reported for only a small minority of trials. Overall, recurrences did not differ between groups, but comparison of laparoscopic with open non-mesh repair favoured laparoscopic methods, significantly so for transabdominal preperitoneal repair (Peto odds ratio 0.56 (95 per cent confidence interval 0.33-0.93); P = 0.026). CONCLUSION: Although the rigorous search maximized trial identification, variation in trial reporting made formal meta-analysis difficult. Laparoscopic repair was associated with less postoperative pain and more rapid return to normal activities, but it takes longer to perform and may increase the risk of rare, but serious, complications.

Hernia, Inguinal↗

PubMed1996

A randomized controlled trial of laparoscopic extraperitoneal hernia repair as a day surgical procedure.

BACKGROUND: A randomized controlled trial was conducted in a day surgery setting comparing a standardized variant of the Shouldice hernioplasty with extraperitoneal laparoscopic herniorrhaphy. METHODS: The laparoscopic repair was technically challenging, evidenced by conversion from extraperitoneal to transabdominal repairs in 6.25% of patients. It was free from the inherent dangers of intraperitoneal laparoscopy. Surgical morbidity was low and comparable to that for patients randomized to the open repair. RESULTS: Outcome following laparoscopic extraperitoneal herniorrhaphy varied depending on the parameter measured. It was comparable to the open repair with respect to postoperative activity levels and the number of days required for return to work but inferior to the open repair in terms of operation time and time to hospital discharge. The extraperitoneal approach was superior to the open repair with respect to postoperative pain levels and analgesic requirements. No attempt was made to compare recurrence rates due to the short follow-up period. CONCLUSIONS: Laparoscopic extraperitoneal herniorrhaphy should not supercede conventional hernia repair until subjected to further trials with the aid of larger study populations and greater technical expertise; the results of long-term recurrence rates are awaited.

Adolescent↗

PubMed2004

Valproic acid has no effect on pain in polyneuropathy: a randomized, controlled trial.

The aim of this randomized, double-blind, placebo-controlled cross-over study was to test whether valproic acid relieves painful polyneuropathy. Thirty-one patients completed two treatment phases of 4 weeks' duration with valproic acid (1,500 mg daily) and placebo. There was no significant difference between valproic acid and placebo in the rating of total pain (median, 5 in the valproic acid period vs 6 in the placebo period; p = 0.24) or in individual pain ratings.

Adult↗

PubMedDate not supplied

Comparison of meperidine plus midazolam and fentanyl plus midazolam in procedural sedation: a double-blind, randomized controlled trial.

This double-blind, randomized, prospective study was conducted to compare the analgesic and sedative efficacy of fentanyl and meperidine in orthopedic closed reduction of fractures and dislocations undertaken in the emergency department. Seventy consecutive adult patients with fractures or dislocations suitable for reduction were randomized to receive fentanyl (1 mcg/kg; n = 36) or meperidine (0.5 mg/kg; n = 34) in combination with midazolam (0.02 mg/kg). Vital signs and alertness scale scores of the patients were monitored. The Visual Analog Scale (VAS) was used to determine the degree of pain. There was no statistically significant difference between the VAS mean scores of the fentanyl and meperidine groups (t test, P = .772). The need for additional analgesic drugs was significantly more frequent in patients receiving meperidine (P = .018). No adverse events, such as hypotension or respiratory depression, were noted. Euphoria occurred in one patient in the fentanyl group. Although dose requirements differ, fentanyl and meperidine provide effective and reliable analgesia in closed reduction of fractures and dislocations.

Adult↗

PubMed2003

Improved risk-benefit ratio for topical triamcinolone acetonide in Transfersome in comparison with equipotent cream and ointment: a randomized controlled trial.

BACKGROUND: Transfersome is a drug delivery technology based on highly deformable, ultraflexible lipid vesicles which penetrate the skin when applied non-occlusively. OBJECTIVES: To assess the advantages of this carrier-based formulation in humans, the efficacy and the atrophogenic potential of triamcinolone acetonide (TAC) in Transfersome was compared with commercially available TAC-containing cream and ointment. METHODS: Healthy volunteers were enrolled in double-blind, placebo-controlled clinical trials with random study medication assignment to the test areas. RESULTS: A 10-fold lower dose of TAC in Transfersome(R) (2.5 micro g cm-2) was bioequivalent to 25 micro g cm-2 TAC in conventional formulations as measured by erythema suppression (cream: P = 0.01, ointment: P < 0.001). A skin blanching assay revealed different kinetics of the formulations, with a delayed onset of action of the Transfersome and ointment preparations. Ultrasonic measurements revealed a significantly reduced atrophogenic potential. There was a 12.1% reduction in skin thickness given by TAC in Transfersome compared with a 21.1% reduction given by a bioequivalent dose in TAC cream after a 6-week treatment period (P = 0.007). CONCLUSIONS: Transfersome may significantly improve the risk-benefit ratio of topically applied glucocorticosteroids.

Administration, Topical↗

PubMed2004

Comparing the fixed combination dorzolamide-timolol (Cosopt) to concomitant administration of 2% dorzolamide (Trusopt) and 0.5% timolol -- a randomized controlled trial and a replacement study.

PURPOSE: To compare the intraocular pressure (IOP) lowering effect of concomitant administration of 0.5% timolol and 2% dorzolamide and a fixed combination dorzolamide-timolol (Cosopt) To critically evaluate discrepancies between phase 3 clinical trials and prior replacement studies. DESIGN: A prospective, randomized, controlled clinical trial and a prospective, non-randomized comparative replacement trial. PARTICIPANTS/INTERVENTIONS: In a national multicentre trial, 131 patients were randomized to dorzolamide-timolol or a topical carbonic anhydrase inhibitor (CAI) and non-selective beta-blocker following a 1-month run-in using the separate components. Peak (maximal drug effect) and trough (minimal drug effect) IOPs were measured at baseline and 1 month after treatment. The replacement therapy study enrolled 404 consecutive glaucoma patients using a non-selective beta-blocker and dorzolamide and changed treatment to the fixed combination. Mean IOPs at the same time of day were compared before and 1 month after changeover. MAIN OUTCOME MEASURE: The main outcome measure was IOP, comparing baseline and on-therapy measurements at study conclusion between the two arms of the randomized trial and before and after switching therapy in the replacement trial. RESULTS: In the randomized trial, the mean baseline peak and trough IOPs were 18.4 and 21.0 mmHg in the group randomized to combination therapy and 17.6 and 19.8 mmHg in the dual drug group. After randomization and treatment for four weeks, the peak and trough IOPs were 17.6 and 19.5 mmHg in the combination group and 17.3 and 19.0 mmHg in the concomitant group. The percentage change in IOP was -3.2% at peak and -6.5% at trough for the combination and -0.3 and -3.2% for the concomitant group. These differences did not show statistical significance. In the replacement study, mean baseline IOP was 19.4 mmHg. Four weeks after initiation of treatment on the fixed combination, a significant additional IOP reduction of 1.7 mmHg (-8.8%) was observed (P < 0.0001). Overall, 81% of eyes exhibited equal or lower IOP on the fixed combination compared with concomitant therapy. CONCLUSION: The results of the randomized trial indicate that the fixed combination dorzolamide-timolol (Cosopt) was as effective as its components in controlling IOP, confirming results seen in phase 3 clinical trials. However, in the replacement study, utilization of the combination drug offered a statistically significant additional IOP reduction (P < 0.0001), which duplicates results from previous replacement studies.

Aged↗

PubMed1997

Are randomized controlled trials controlled? Patient preferences and unblind trials.

The most reliable information about treatment effects comes from randomized controlled trials (RCTs). However, the possibility of subtle interactions--for example, between treatment preferences and treatment effects--is generally subordinated in the quest for evidence about main treatment effects. If patient preferences can influence the effectiveness of treatments through poorly understood (psychological) pathways, then RCTs, particularly when unblinded, may wrongly attribute effects solely to a treatment's physiological/pharmacological properties. To interpret the RCT evidence base it is important to know whether any preference effects exist and, if so, by how much they affect outcome. Reliable measurement of these effects is difficult and will require new approaches to the conduct of trials. In view of the fanciful image with which such effects are portrayed and the uncertainties about their true nature and biological mechanisms, existing evidence is unlikely to provide sufficient justification for investment in trials. This is a Catch 22. Until an escape is found we might never know, even approximately, how much of modern medicine is attributable to psychological processes.

Humans↗

PubMed2000

Effects of three-month oral supplementation of beta-carotene and vitamin C on serum concentrations of carotenoids and vitamins in middle-aged subjects: a pilot study for a randomized controlled trial to prevent gastric cancer in high-risk Japanese population.

Prior to a randomized controlled trial to prevent gastric cancer by oral supplementation of beta-carotene and vitamin C in a high-risk Japanese population, we examined the serum response to three-month oral supplementation of beta-carotene (0, 3, 30 mg / day) and vitamin C (0, 50, 1000 mg / day) by a three-by-three factorial design using 54 subjects (age range = 40 - 69 years). Serum concentrations of carotenoids, alpha-tocopherol, and ascorbic acid were examined at baseline, and one, two, and three-month points. Both serum beta-carotene and ascorbic acid were significantly higher in high-dose groups than in each placebo group during the supplementation. The serum beta-carotene increased gradually (597 - 830% increase) during the study, whereas the serum ascorbic acid reached nearly a steady-state at the one-month point and remained stable thereafter (88 - 95% increase). No statistically significant interaction between beta-carotene and vitamin C supplementations was observed either for serum beta-carotene or for serum ascorbic acid. Among carotenoids and alpha-tocopherol examined, serum lycopene in the high-dose beta-carotene group was significantly higher than in the placebo group at all points. No unfavorable change in carotenoids and alpha-tocopherol was observed in any group.

Administration, Oral↗

PubMed2001

Tamoxifen for the prevention of breast cancer: psychosocial impact on women participating in two randomized controlled trials.

PURPOSE: The purpose of this study was to evaluate the psychosocial implications of tamoxifen versus placebo in women who are at increased risk of breast cancer. PATIENTS AND METHODS: The 488 women in the psychosocial study were recruited from participants in two placebo-controlled, double-blind, randomized, controlled trials that investigated the efficacy of tamoxifen in the prevention of breast cancer in women who are at high familial risk. During a 5-year period, repeated assessments were made of anxiety, psychological distress, and sexual functioning using standardized questionnaires before treatment at baseline and at 6-month intervals during the trial. RESULTS: Questionnaire completion over 5 years was good, with 71.1% of women returning at least 8 of 10 follow-up assessments. Although scores from individuals showed considerable fluctuation and variation over time, changes in anxiety, mood, and sexual functioning were not associated with treatment group. The number of symptoms reported at 48 months via a self-report checklist were not associated with treatment group, but vasomotor symptoms were more frequent among tamoxifen-treated women. Symptoms of low energy, breast sensitivity, and visual blurring were reported most frequently in the placebo group. CONCLUSION: In general, these results are comparable to those from the National Surgical Adjuvant Breast and Bowel Project psychosocial study despite differences in study populations, methodology, and instruments. The long-term use of tamoxifen and other selective estrogen response modulators as preventive agents in high-risk groups has been questioned, but we found no evidence of treatment-related side effects that affect women's psychosocial and sexual functioning.

Adult↗

PubMed1998

What can we conclude from the randomized controlled trials of fecal occult blood test screening?

The results of three published randomized controlled trials of fecal occult blood testing (FOBT) provide unequivocal proof of the principle that screening reduces mortality from colorectal cancer (CRC). However, several interesting questions remain in interpreting and applying the results of the clinical trials, including: how well does FOBT screening work (i.e. how much can CRC mortality be reduced), how does it work, when is it worthwhile and worthwhile doing, and how can technique be optimized? The answers to these questions have important practical and clinical implications.

Age Factors↗

PubMed1995

Assessing the quality of randomized controlled trials: an annotated bibliography of scales and checklists.

Assessing the quality of randomized controlled trials (RCTs) is important and relatively new. Quality gives us an estimate of the likelihood that the results are a valid estimate of the truth. We present an annotated bibliography of scales and checklists developed to assess quality. Twenty-five scales and nine checklists have been developed to assess quality. The checklists are most useful in providing investigators with guidelines as to what information should be included in reporting RCTs. The scales give readers a quantitative index of the likelihood that the reported methodology and results are free of bias. There are several shortcomings with these scales. Future scale development is likely to be most beneficial if questions common to all trials are assessed, if the scale is easy to use, and if it is developed with sufficient rigor.

Bias↗