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Results for “randomized crossover trial”

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PubMed2005

Effects of ankle support on lower-extremity functional performance: a meta-analysis.

UNLABELLED: Clinicians surmise that the application of external ankle support reduces the ability to perform functional skills and movements, but the outcomes from some of these studies have been inconclusive. PURPOSE: To meta-analyze studies regarding the effects of external ankle support on lower-extremity functional performance measures. METHODS: A total of 93 effects from 17 randomized controlled trials utilizing predominantly crossover designs with recreationally active participants and competitive athletes were subjected to a random-effects meta-analysis. The treatment variable was external ankle support with three levels: adhesive tape, lace-up style, and semirigid style. Differences between mean changes in treatment and control groups were computed as standardized effect sizes for sprint, agility, and vertical jump performance with their 90% confidence intervals (CI). Effect sizes >0.20 were considered substantial. RESULTS: The greatest effect of ankle support on performance was a negative effect of lace-up style brace on sprint speed (effect size -0.22, 90% CI -0.47 to 0.03), equivalent to approximately 1% impairment of speed. The other effects of external ankle support on performance were insubstantial, though most were negative, and their lower confidence limits allowed for realistic chances of impaired performance. Substantial true variation between studies, although poorly defined, was also present for some effects, further increasing the likelihood of performance impairment in some settings. CONCLUSIONS: More research is needed to reduce the uncertainty in the effects of external ankle support on performance. In the meantime, it is our opinion that the benefit in preventing injury outweighs the possibility of substantial but small impairment of performance when athletes use external ankle support.

Ankle↗

PubMed2002

A randomized, double-blind, single-dose, crossover clinical trial of the onset and duration of protection from exercise-induced bronchoconstriction by formoterol and albuterol.

BACKGROUND: Inhaled short-acting beta(2)-adrenoceptor agonists are the most commonly used treatment for the prevention of exercise-induced bronchoconstriction (EIB). Formoterol, a long-acting beta(2)-adrenoceptor agonist, has been demonstrated to provide protection from EIB, although the onset and duration of this protection have not been defined. OBJECTIVE: The purpose of this study was to determine the onset and duration of the protective effect of a single dose of inhaled formoterol powder against EIB, comparing them with the effect of a single dose of placebo and albuterol administered via metered-dose inhaler (MDI). METHODS: In this double-dummy, 4-way crossover study, patients received single doses of formoterol (12 and 24 microg) via a powder inhaler, albuterol by MDI (180 microg), and placebo. Exercise challenge tests (ECTs) were conducted at 15 minutes and at 4, 8, and 12 hours postdose. Pulmonary function studies (forced expiratory volume in 1 second [FEV(1)] and peak expiratory flow rate) were performed before and after each exercise challenge. RESULTS: Twenty adolescent and adult patients (mean age, 23.8 years; range, 13-41 years; 9 male, 11 female) with asthma were enrolled in the study, and 17 completed all 4 treatment sequences. Compared with placebo, both doses of formoterol produced significantly greater inhibition of FEV(1) decreases at all time points (P < 0.01). There were no significant differences in efficacy measures between the 2 formoterol doses throughout the study. The exercise-induced decrease in FEV(1) after albuterol treatment was significantly reduced compared with placebo only at 15 minutes after dosing (P < 0.05). Formoterol and albuterol exhibited a similar rapid onset of action (<15 minutes), but formoterol continued to protect patients against EIB for at least 12 hours (P < 0.01), whereas albuterol was no longer clinically effective by the 4-hour ECT. CONCLUSIONS: Formoterol and albuterol, given as single-dose inhalations, both provided protection from EIB within 15 minutes in this group of patients. The bronchoprotection afforded by formoterol lasted up to 12 hours, whereas that of albuterol was no longer significant by 4 hours.

Administration, Inhalation↗

PubMed1998

Warmed versus room temperature saline solution for ocular irrigation: a randomized clinical trial.

STUDY OBJECTIVE: To test the hypothesis that ocular irrigation with warm saline solution is more comfortable than irrigation with room temperature saline solution in normal volunteers. METHODS: The study was a randomized, single-blind crossover trial, in which each subject received 30 mL warmed and 30 mL room temperature saline solution in opposite eyes. The solutions (warmed versus room temperature) and the order of irrigation (right eye versus left) were separately randomized. Physicians were blinded to solution temperature. Subjects rated the discomfort of irrigation on separate visual analog scales (VAS). The study had 80% power to detect at least a 12-mm difference in VAS readings. RESULTS: Thirty-five volunteers were enrolled in the study. There was no gender effect or order effect for the 2 solutions. The mean VAS score for warmed saline solution was 15 mm+/-15 mm (SD). The mean VAS score for room temperature saline was 34 mm+/-24 mm (SD), (95% confidence interval for difference of 19 mm [10 mm to 28 mm], P <.0001, Wilcoxon signed rank test). CONCLUSION: Warmed saline solution was both clinically and statistically more comfortable than room temperature saline solution as an ocular irrigant among normal volunteers.

Adult↗

PubMed2003

Impact of low-dose acetylsalicylic acid on kidney function in type 2 diabetic patients with elevated urinary albumin excretion rate.

BACKGROUND: Low-dose treatment with acetylsalicylic acid (ASA) is widely recommended to type 2 diabetic patients as primary prevention against cardiovascular disease. High-dose treatment with cyclooxygenase inhibitors reduces urinary albumin excretion rate (AER) in type 1 diabetic patients with micro- or macroalbuminuria. Whether a similar effect on AER exists during low-dose ASA treatment, which may confound the diagnosis and monitoring of micro- and macroalbuminuria in type 2 diabetic patients, remains to be elucidated. METHODS: In a randomized, double-blind, crossover trial, 31 type 2 diabetic patients with elevated levels of AER (>30 mg/24 h) were, in random order, given ASA (150 mg/day) for 4 weeks followed by placebo for 4 weeks with a 2 week washout period or vice versa. At the end of each treatment period AER, glomerular filtration rate (GFR), blood pressure (BP), transcapillary escape rate (TER(alb)) of albumin and haemoglobin A(1c) (HbA(1c)) were measured. RESULTS: The following variables remained unchanged (mean (95% CI) unless otherwise noted) (ASA vs placebo, paired Student's t-test): AER (201 (119-341) vs 205 (124-340) mg/24 h (geometric mean, 95% CI); P=0.78), GFR (103 (94-111) vs 102 (93-110) ml/min; P=0.58), systolic BP (151 (146-158) vs 152 (146-158) mmHg; P=0.68), diastolic BP (87 (83-91) vs 87 (82-91) mmHg; P=0.88), TER(alb) (6.3 (5.7-6.9) vs 5.9 (5.1-6.7); P=0.45) and HbA(1c) (8.6 (8.1-9.0) vs 8.5 (8.1-9.0) %; P=0.60). CONCLUSIONS: Low-dose treatment with 150 mg ASA daily does not have any impact on AER or GFR in type 2 diabetic patients with micro- or macroalbuminuria. Consequently, the widely recommended prescription of low-dose ASA as a primary and secondary prevention strategy against cardiovascular disease in these patients does not confound the diagnosis or monitoring of micro- or macroalbuminuria.

Adult↗

PubMed2002

Comparison of the effects of three insulinotropic drugs on plasma insulin levels after a standard meal.

OBJECTIVE: To compare the effects of repaglinide, glipizide, and glibenclamide on insulin secretion and postprandial glucose after a single standard 500-kcal test meal. RESEARCH DESIGN AND METHODS: A total of 12 type 2 diabetic patients with early diabetes (mean HbA(1c) of 6.1%) and 12 matched control subjects were enrolled in this randomized, double-blind, crossover trial. Subjects received placebo, 2 mg repaglinide, 5 mg glipizide, and 5 mg glibenclamide in a random fashion during the trial. Administration of each drug was followed by a single standard 500-kcal test meal. A washout period of 7-12 days existed between the four study visits. RESULTS: All three drugs were equally effective on the total prandial insulin secretion (area under the curve [AUC] -15 to 240 min). However, clear differences were noted in the early insulin secretion (AUC -15 to 30 min); both repaglinide and glipizide increased secretion in nondiabetic subjects by approximately 61 and 34%, respectively, compared with placebo. In the diabetic patients, the difference versus placebo was 37 and 47%, respectively. The difference between glipizide and glibenclamide reached significance in both groups of subjects, whereas repaglinide was more effective than glibenclamide only in the healthy nondiabetic subject group. All three drugs were effective in decreasing total glucose AUC in the nondiabetic and diabetic population. In the nondiabetic subjects, however, repaglinide was significantly more effective than glibenclamide. The differences disappeared in the diabetic subjects, probably as a result of increased prevalence of insulin resistance in this group. CONCLUSIONS: Repaglinide and glipizide but not glibenclamide significantly enhanced the early insulin secretion in both nondiabetic and diabetic subjects with preserved beta-cell function after a single standard meal.

Aged↗

PubMed1989

Effect of decaffeinated versus regular coffee on blood pressure. A 12-week, double-blind trial.

The effect of decaffeinated versus regular coffee on blood pressure and heart rate was investigated. In a randomized double-blind, crossover trial, 45 healthy volunteers (23 women and 22 men, 25-45 years old) with a habitual intake of 4-6 cups coffee/day received 5 cups of regular coffee each day for a period of 6 weeks, and 5 cups of decaffeinated coffee for the next 6 weeks or vice versa. The background diet was kept constant. The total amount of caffeine ingested was 40 mg during the decaffeinated coffee period and 445 mg during the regular coffee period. Use of decaffeinated coffee led to a significant but small decrease in systolic (mean +/- SEM, -1.5 +/- 0.4 mm Hg; p = 0.002) and diastolic (-1.0 +/- 0.4 mm Hg; p = 0.017) ambulant blood pressure and to a small increase in ambulant heart rate (+1.3 +/- 0.6 beats/min; p = 0.031). Individual differences in rate of caffeine metabolism did not explain differences in long-term response of blood pressure to caffeine. We conclude that in normotensive adults replacement of regular by decaffeinated coffee leads to a real but small fall in blood pressure. However, it remains to be established whether a mass switch from regular to decaffeinated coffee would significantly reduce the total incidence of hypertension-related disorders.

Adolescent↗

PubMed1999

Phase 1 trial of nonoxynol-9 film among sex workers in South Africa.

OBJECTIVES: To assess the acceptability and safety of a vaginal nonoxynol-9 film in a group of sex workers at a truck stop in South Africa. DESIGN: A randomized double-blinded crossover trial was conducted between April 1995 and July 1995. INTERVENTION: Seventy-two mg nonoxynol-9 film and an identical glycerine placebo film. METHODS: Following informed consent, each study participant was randomly assigned the designated pre-coded film for 1 month. The second month was a film-free washout period and the participants used the alternate film in the third month. Besides measuring behavioural and clinical outcomes, colposcopy examination for genital lesions, serology and microbiology investigations for sexually transmitted diseases and semi-quantitative PCR for vaginal HIV load estimates were performed. RESULTS: Twenty women participated in the study. The women reported, on average, 19 sexual encounters per week. Vaginal intercourse was protected 25% of the time by condoms. On average, 11 vaginal films, either nonoxynol-9 or placebos were inserted per week. There were no statistically significant differences between the two treatment groups for genital lesions (P = 0.29), reported side effects (P = 0.73), and viral load (P = 0.9). However, the proportions of clinically detected genital lesions (six out of eight versus two out of eight) and self-reported side-effects (five out of eight versus three out of eight) were higher in the nonoxynol-9 group when compared with the placebo group. Incident sexually transmitted diseases occurred more frequently in the placebo group. An increased viral load was associated with the development of a genital lesion (relative risk, 6.0; 95% confidence interval, 0.81-44.4). CONCLUSIONS: The 72 mg film formulation of nonoxynol-9 was an acceptable product for use in this population of sex workers. Although no statistically significant differences in adverse outcomes were detected, clinically there appeared to be an increase in minor lesions and self-reported side-effects with nonoxynol-9 and less protection against sexually transmitted diseases with the placebo. Furthermore, HIV shedding was correlated with the presence of incident vaginal or cervical lesions. This brings into question the potential narrow margin of safety for this product; additional Phase 2 studies are therefore required.

Administration, Intravaginal↗

PubMed1991

Alcohol after midazolam sedation: does it really matter?

Patients who arrive home several hours after ambulatory surgery may drink alcohol. The extent to which the residual effects of drugs used in ambulatory surgery interact with alcohol, perhaps potentiating alcohol effects, is not known. Accordingly, the purpose of this study was to determine whether intravenous midazolam had residual effects that would interact with alcohol consumed 4 h after the midazolam injection. Healthy male volunteers (n = 16) participated in a double-blind, randomized, placebo-controlled crossover trial. Subjects were studied four times successively with 1 wk between trials. On each test day the subjects randomly received by slow intravenous injection (30 s) either saline or 0.1 mg/kg of midazolam. Four hours after injection, the subjects consumed a beverage that either did or did not contain 0.7 g/kg of alcohol. Before and 1, 3, 5, and 7 h after injection (and before and 1 and 3 h after beverage consumption), psychomotor performance and mood were assessed. Whereas both midazolam and alcohol alone had effects on the dependent measures in this study, there were no significant interactions between the two drugs (i.e., potentiation of alcohol effects by midazolam or potentiation of midazolam by alcohol). We conclude that the effects of a short-acting benzodiazepine used in ambulatory surgery have probably dissipated by the time a patient arrives home, and that effects from alcohol ingested at home will probably not be influenced by the recent administration of a short-acting benzodiazepine such as midazolam.

Adult↗

PubMed1988

Comparative evaluation of gastrointestinal intolerance produced by plain and tri-buffered aspirin tablets.

Two multi-investigator, double-blind, randomized, placebo-controlled, crossover trials were conducted to determine whether tri-buffered formulations of both regular strength aspirin and extra strength aspirin would be less likely than plain aspirin to provoke subjective gastrointestinal (GI) intolerance. Each trial was divided into two phases, a qualification phase and a test phase. During the qualification phase, subjects with a history of gastrointestinal intolerance to aspirin were randomized to a double-blind crossover treatment with aspirin and placebo (325 mg aspirin per tablet in study 1 and 500 mg aspirin per tablet in study 2), two tablets four times a day for 3 days or until the occurrence of stomach upset. Subjects who reported gastrointestinal symptoms with aspirin and not with placebo qualified to participate in the test phase of the study. They were rerandomized to participate in a three-way crossover study of plain aspirin, tri-buffered aspirin, and placebo in the test phase. Tri-buffered aspirin was associated with an appreciable reduction in the incidence of gastrointestinal upset relative to plain aspirin, 34 percentage points in study 1 (p less than 0.001) and 33 percentage points in study 2 (p less than 0.001). Similar results were obtained in the evaluation of the reduction of the severity of gastrointestinal symptoms.

Adult↗

PubMed1990

Frequency of adverse reactions to influenza vaccine in the elderly. A randomized, placebo-controlled trial.

Concern about side effects constitutes a major deterrent to patient compliance with influenza vaccination, yet there is a paucity of data about the occurrence of adverse reactions in the population targeted for immunization. We conducted a randomized, double-blind, crossover trial to compare the frequency of adverse reactions following administration of 1988-1989 trivalent split-antigen influenza vaccine and saline placebo. Outpatient veterans 65 years of age or over (n = 336) were recruited by mail and were randomly assigned to receive vaccine followed 2 weeks later by placebo injection or placebo followed 2 weeks later by vaccine. There was no significant difference between influenza vaccine and placebo with respect ot the proportion of subjects reporting disability or systemic symptoms.

Aged↗

PubMed1977

Comparative effects of tolfenamic acid and acetylsalicylic acid on human gastric mucosa. A double-blind crossover trial employing gastroscopy, extern gastrocamera and multiple biopsies.

A comparative study has been made of the effects of tolfenamic acid (Clotam) and acetylsalicyclic acid on the gastric mucosa in 10 healthy volunteers. The effects were evaluated by means of gastroscopy, photography of the gastric mucosa, and multiple biopsies. The schedule was for a randomized, double-blind crossover trial involving two drug-administered periods of one week's duration separated by an interval of at least 3 weeks. On each day of the drug-administration weeks either tolfenamic acid 600 mg or acetylsalicyclic acid 3 g was administered as three divided doses, taken with meals. Gastroscopy was performed prior to and after each week of drug administration. Subjective side effects were recorded during the therapy periods; haematemesis occurred in 2 volunteers taking acetylsalicyclic acid. The absence of gastritis in each subject during treatment with tolfenamic acid was confirmed both gastroscopically and histologically. In contrast, 6 out of 10 volunteers developed mild superficial acute gastritis after ingestion of acetylsalicyclic acid. The difference in effect between the two treatments on the gastric mucosa was statistically significant(p less than 0.05). The findings of this study are comparable to those of other studies and it is concluded that tolfenamic acid, in the relatively high dosage employed in this trial, is free from any irritant effect on the gastric mucosa.

Adult↗

PubMed1989

Once or twice daily theophylline in childhood asthma.

We conducted a randomized, single-blind, crossover trial to compare two sustained release theophylline preparations. Fifty-nine chronic asthmatics, aged 7-14 years, were randomly allocated to receive Slophyllin (SP) twice daily followed by Uniphyllin (UP) taken as a single dose at bedtime, or UP followed by SP. Two 4-week periods on therapeutic doses of each preparation were compared. Thirty-six patients completed the study. Eight were non-compliant, seven defaulted and eight withdrew because of theophylline related side-effects (seven on UP). Symptom scores, beta-agonist usage, compliance by pill counts, evening peak flow rates and maximal expiratory flow-volume curves were similar on both treatments. Blood levels of theophylline at 11 am and morning peak flow rates were significantly higher on UP. UP may be more helpful for patients with early morning symptoms, but is associated with an increased frequency of severe side effects.

Adolescent↗

PubMed1999

Warmed versus room temperature saline solution for ear irrigation: a randomized clinical trial.

STUDY OBJECTIVE: To test the hypothesis that ear irrigation with warmed normal saline solution is more comfortable and results in fewer side effects than irrigation with room temperature saline solution in normal volunteers. METHODS: The study was a randomized, single-blind, crossover trial in which each subject received 30 mL warmed normal saline solution in 1 ear and 30 mL room temperature saline solution in the opposite ear. The solutions (warmed versus room temperature) and the order of irrigation (right versus left ear) were separately randomized. Investigators obtaining scores were blinded to solution temperature. Subjects rated the discomfort of irrigation, using separate visual analog scales, from 0 (no pain) to 100 mm (worst pain ever). RESULTS: Forty volunteers were enrolled in the study. The mean difference in visual analog scale scores favoring warmed over room temperature saline solution was 26 mm (95% confidence interval [CI], 19 to 33 mm; P <.0001). Twenty percent more patients reported dizziness with room temperature irrigation (95% CI, 6% to 34%). There was no gender effect or order effect for the 2 solutions. CONCLUSION: Warmed normal saline solution was both clinically and statistically more comfortable than room temperature saline solution as an ear irrigant in normal volunteers. Significantly less dizziness was reported with the warmed solution.

Adult↗

PubMedDate not supplied

Comparative study of the analgesic efficacy of flurbiprofen and diclofenac in patients following excimer laser photorefractive keratectomy.

This randomized, patient-masked, crossover trial compared the analgesic efficacy of flurbiprofen and diclofenac in 16 patients following excimer laser photorefractive keratectomy. Patients were randomly assigned to receive one study medication after surgery on the first eye and the other medication after surgery on the second eye (approximately 30 days later). After both surgeries, patients instilled one drop of the assigned medication six times daily for the first 3 days postsurgery and one drop four times daily on postsurgery days 4 through 7. Patients assessed the intensity of postsurgical pain beginning at postsurgery hour 5 and pain relief beginning at postsurgery hour 8 and continued to do so daily thereafter. On the last day (day 7), patients rated the global efficacy of the analgesic treatment. All assessments were performed by patients using descriptor and visual ordinal scales and were recorded in diaries. Patients were queried as to the presence, severity, and duration of any adverse events. Flurbiprofen produced significantly greater reductions in pain intensity than did diclofenac at all evaluations through day 4 and significantly greater relief of pain than did diclofenac at all evaluations through day 3. Significantly more patients treated with flurbiprofen reported being pain free on days 3 and 4 (11 [69%] and 16 [100%], respectively) compared with those treated with diclofenac (3 [19%] and 9 [56%], respectively). Based on patient ratings, flurbiprofen had significantly better global analgesic activity than diclofenac. Both treatments were well tolerated. Mild and transient ocular burning after instillation was the only reported adverse event; it was reported by all patients in both study groups at approximately 50% of study visits.

Adult↗

PubMed2001

Plasma exchange for severe attacks of inflammatory demyelinating diseases of the central nervous system.

Plasma exchange has not been widely accepted as a treatment for multiple sclerosis. However, several uncontrolled studies have suggested that patients with severe attacks of MS and other inflammatory demyelinating disease may improve rapidly after plasma exchange treatment. We recently completed a randomized, sham-controlled, crossover clinical trial of plasma exchange in 22 patients with idiopathic inflammatory demyelinating diseases of the central nervous system. Twelve had MS and ten had other inflammatory demyelinating disease syndromes. Forty-two percent of patients experienced moderate or greater recovery over 2 weeks of active treatment administered every other day while only 6% of patients experienced similar improvement while receiving sham treatment. Three patients who failed the sham treatment subsequently improved rapidly after crossover to active treatment; no patient who failed active treatment improved after crossover to sham. This study illustrates the importance of designing randomized clinical trials based on the treatment regimen and patient population studied in the uncontrolled reports that suggested treatment efficacy. Plasma exchange should be considered for patients with idiopathic inflammatory demyelinating disease syndromes when they have failed corticosteroid therapy.

Demyelinating Autoimmune Diseases, CNS↗

PubMed2004

Redesigned face mask improves "real life" aerosol delivery for Nebuchamber.

The currently available facemask interface for the Nebuchamber (N) valved-holding chamber (VHC) provides a very poor seal to the face, which, on average, decreases the aerosol dose and was previously shown to increase the variability of aerosol delivery. The efficiency of a redesigned mask (RD) for the Nebuchamber with a potentially better seal was compared to the standard mask (SM) supplied with the N in a randomized real-life crossover clinical trial. Twenty children (mean age, 26 +/- 10 months) were randomized to use the Nebuchamber for 1 week with the old mask and then for another week with the newer mask, and vice versa. Filters, changed daily, inserted between the mask and the VHC, trapped the delivered drug (budesonide). The dose of budesonide was quantified by high-performance liquid chromatography (HPLC). Use of the redesigned mask improved aerosol delivery to the filter by 30%, compared to the SM (mean 28.1 +/- 7.7% of nominal dose with RD vs. 21.6 +/- 9.6% with SM, P = 0.017). The relatively high within-subject variability in aerosol delivery (36-38%) did not change, however. Facemasks are arguably the most important determinants of aerosol delivery. The newly developed RD for the Nebuchamber proved to be considerably more efficient than the SM for aerosol delivery to young children. Patient-related factors may be more important with respect to the variability observed.

Asthma↗

PubMed1986

A trial of intranasal Atrovent versus placebo in the treatment of vasomotor rhinitis.

Twenty-six patients with perennial rhinorrhea were treated by Atrovent, the anticholinergic agent, or placebo in a randomized double-blind crossover trial. The severity and duration of rhinorrhea were significantly reduced by Atrovent. Local side effects were more frequent with the active drug. These were reduced in a later open trial by a reduction in dosage.

Administration, Intranasal↗

PubMed1985

Effect of bepridil in patients with chronic stable angina: results of a multicenter trial.

The effects of bepridil, a calcium antagonist with a half-life of approximately 42 hr, were assessed in a double-blind, randomized, placebo-controlled crossover trial. Forty-four patients (39 men, five women) with exercise-induced angina pectoris and ST segment depression with exercise testing (modified Bruce protocol) were studied. Compared with placebo bepridil (400 mg daily) increased total exercise time, time to onset of angina, time to 1 mm of ST segment depression, time to 2 mm of ST segment depression, and total work achieved (all p less than or equal to .001). Both frequency of angina and nitroglycerin consumption decreased during the bepridil compared with the placebo period (p = .02 and .03, respectively). Minor side effects were noted during both the bepridil and placebo phases. Four patients experienced side effects that limited therapy (dizziness in three and abnormal results of liver function tests in one) and one patient died during the bepridil phase. This study suggests that bepridil, 400 mg daily, is effective for the treatment of exercise-induced myocardial ischemia and angina pectoris.

Angina Pectoris↗