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Results for “randomized trial”

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PubMed1987

Fast neutron therapy for squamous cell carcinoma in the head and neck region: results of a randomized trial.

A randomized trial of fast neuron therapy compared with 4MV photons for patients with head and neck cancer is reported. One hundred and sixty-eight patients were recruited between 1977 and 1984. The minimum follow-up is 2 years. Three patients were withdrawn before treatment began. Eighty-five were allocated to neutron therapy and 80 to receive photon therapy. All patients had squamous cell cancers in one of four primary sites: oral cavity, oropharynx, larynx, and hypopharynx. Local tumor control was similar in both groups: 44.7% after neutrons and 45.0% after photons. Salvage surgery was performed on 18 patients in each treatment group for residual or recurrent cancer. Acute radiation reactions of the mucous membranes were significantly more severe after photons. The number of patients with serious late reactions was greater after neutron therapy but the difference was not statistically significant. There were six deaths related to late morbidity after neutron therapy but none after photon therapy. Survival was better after photon therapy but the difference compared with the neutron group failed to reach statistical significance. When intercurrent deaths are excluded, the difference is less marked. Photon therapy was clearly better in terms of disease-free survival giving a 2-year local disease-free rate of 41.3% (s.e. 5.5%) compared with 29.4% (s.e. 4.9%) after neutrons.

Carcinoma, Squamous Cell↗
PubMed1988

Compliance for low-back pain patients in the emergency department. A randomized trial.

A randomized trial was used to evaluate two forms of a Health Belief Model (HBM) intervention aimed at increasing compliance among low-back pain (LBP) patients visiting an Emergency Department (ED). Patients who received an HBM clinical intervention administered in the ED, HBM phone intervention made 1 to 2 days post-ED visit, or both interventions were much more likely than control patients to both schedule and keep a follow-up referral appointment. Both the phone and clinical interventions were designed to increase patients' perceived susceptibility to complications of the LBP, seriousness of the complications, and benefits and costs of action through a follow-up referral appointment. Other factors predicting compliance included persistence of pain symptoms, previous treatment of LBP by a health care provider, and an unmet need for child care.

Adult↗
PubMed2001

Selected statistical issues in group randomized trials.

Group randomized trials (GRTs) in public health research typically use a small number of randomized groups with a relatively large number of participants per group. Two fundamental features characterize GRTs: a positive correlation of outcomes within a group, and the small number of groups. Appropriate consideration of these fundamental features is essential for design and analysis. This paper presents the fundamental features of GRTs and the importance of considering these features in design and analysis. It also reviews and contrasts the main analytic methods proposed for GRTs, emphasizing the assumptions required to make these methods valid and efficient. Also discussed are various design issues, along with guidelines for choosing among them. A real data example illustrates these issues and methods.

Humans↗
PubMed2006

Design and analysis of stepped wedge cluster randomized trials.

Cluster randomized trials (CRT) are often used to evaluate therapies or interventions in situations where individual randomization is not possible or not desirable for logistic, financial or ethical reasons. While a significant and rapidly growing body of literature exists on CRTs utilizing a "parallel" design (i.e. I clusters randomized to each treatment), only a few examples of CRTs using crossover designs have been described. In this article we discuss the design and analysis of a particular type of crossover CRT - the stepped wedge - and provide an example of its use.

Adolescent↗
PubMed1989

Effect of a gatekeeper plan on health services use and charges: a randomized trial.

A randomized trial was conducted to determine the effectiveness of a health care plan which uses physicians as gatekeepers to control health services use and charges. New enrollees in United Healthcare (UHC), an independent practice association, were randomly assigned to the standard UHC plan requiring a gatekeeper, or to an alternate plan with equal benefits but without a gatekeeper. Individuals in both plans were similar in demographic characteristics, perceived health status, and other health insurance coverage. The gatekeeper plan had 6 percent lower total charges per enrollee than the plan without a gatekeeper. There were minor differences in hospital use and charges. Ambulatory charges were $21 lower per person per year in the plan with a gatekeeper (95% CI = -39.9, -2.1) and these were due to .3 fewer visits to specialists (95% CI = -0.50, -0.10). We conclude that a health plan which incorporates incentives and penalties for physicians to act as gatekeepers can reduce the cost of ambulatory services by limiting specialist visits.

Adolescent↗
PubMed1997

Misoprostol 3, 4, or 5 days after methotrexate for early abortion. A randomized trial.

A randomized trial was conducted including 287 pregnant women seeking elective abortion to compare the efficacy of misoprostol given 3, 4, or 5 days after methotrexate for abortion at < or = 63 days' gestation. Subjects received 50 mg/m2 methotrexate intramuscularly and were randomly allocated to self-administer vaginally 800 micrograms of misoprostol 3, 4, or 5 days after the methotrexate. The misoprostol dose was repeated 48 and 96 h later if the abortion did not occur. Outcome measures included successful abortion (complete abortion without requiring a surgical procedure), and side effects. Eighty-six cases (93%; 95% confidence interval [CI] 85%-97%) aborted in Group I; 90 cases (92%; 95% CI 84%-96%) aborted in Group II (relative risk [RR] = 1.09; RR 95% CI 0.38-3.14); and 89 (93%; 95% CI 86%-97%) cases aborted in Group III (RR = 0.97; RR 95% CI 0.33-2.87). No significant statistical differences were obtained for the success rates when misoprostol was given days 3, 4, or 5 after the administration of methotrexate (p = 0.97) nor with any of the characteristics of the subjects. Complete abortion occurred in 265/287 (92%; 95% CI 89%-95%) patients. Twenty-two cases (8%; 95% CI 5%-11%) resulted in failure. Side effects for methotrexate were minimal while for misoprostol they were moderate. This combination could be an alternative to surgical abortion or the use of antiprogestins and prostaglandins for medical abortion.

Abortifacient Agents, Nonsteroidal↗
PubMed1985

The antiemetic efficacy of methylprednisolone compared with metoclopramide in outpatients receiving adjuvant CMF chemotherapy for breast cancer: a randomized trial.

A randomized trial was performed comparing the antiemetic efficacy of methylprednisolone (MPN) and metoclopramide (MCP) in 60 breast cancer patients eligible for outpatient adjuvant chemotherapy with cyclophosphamide, methotrexate, and 5-FU (CMF). At the time of their first chemotherapy course patients were randomized to receive either MPN 375 mg or MCP 1 mg/kg both administered in 3 equal doses, IV just prior to chemotherapy and then IM 6 and 12 hours after treatment. Patients receiving MPN experienced significantly less nausea (p less than 0.0005) and vomiting (p less than 0.0005) and antiemetic protection was maintained in patients receiving multiple chemotherapy courses. Complete protection (0 emesis) was observed in 58% of patients receiving MPN as compared with 20% of patients treated with MCP (p less than 0.005). The most frequent side effects were facial flush in 38% of patients and somnolence in 15% of patients receiving MPN and MCP, respectively. Complete protection from CMF-induced gastrointestinal side effects was observed in two-thirds of our patients receiving antiemetic MPN treatment. In these patients administration of the maximum cumulative CMF dose was possible without impairing their quality of life. MPN, at the dose and schedule reported, is an affective antiemetic drug suitable for use in breast cancer outpatients receiving adjuvant CMF therapy.

Adult↗
PubMed1985

Methods of motivating the practice of breast self-examination: a randomized trial.

A randomized trial of 1,733 women compared three methods of motivating the practice of breast self-examination (BSE): (a) cognitive teaching which emphasized factual knowledge; (b) affective teaching which stressed feelings, attitudes, and values; and (c) a mixed approach which combined features of both. Subjects returned for follow-up at 3, 12, and 24 months or at 6 and 12 months, at which times they completed questionnaires and were evaluated by nurses. They demonstrated how they performed BSE and palpated breast models for lumps. No differences were observed among the teaching groups for any of several indicators of BSE practice, such as frequency, knowledge about when to do BSE, technique, or number of lumps detected in the model. However, these measures were associated with women's initial confidence in practicing BSE. Women in all teaching groups improved their BSE technique over time. Women in this study practiced BSE more frequently and detected more lumps than reported in other studies. The better performance of subjects in the present study might be ascribed to the amount of time spent teaching and to reinforcement from repeated follow-ups. The affective and cognitive approaches were equally effective in motivating the practice of BSE.

Adult↗
PubMed1999

Rubber ring clamping of the umbilical cord: a randomized trial.

A randomized trial to compare two methods of umbilical cord tying in neonates, immediately after birth, was undertaken from February to April 1997 in the Department of Obstetrics & Gynaecology, Zewditu Memorial Hospital, Addis Ababa, Ethiopia. In less than 3 months, we investigated 300 neonates, of whom 150 infants were randomly assigned to the traditional ligation of the umbilical cord (using a piece of thread) and the rest to a rubber ring clamping method. Among the former group, 13.3% (20/150) of the neonates bled from their umbilical cords which necessitated re-tying, whereas in the later group, there was no sign of haemorrhage or infection within 12 h of clamping. We suggest that the rubber ring method described is a superior procedure and can easily replace the traditional, cumbersome and time-consuming umbilical cord ligation.

Ethiopia↗
PubMed2006

A randomized trial of tranexamic acid in combination with cell salvage plus a meta-analysis of randomized trials evaluating tranexamic acid in off-pump coronary artery bypass grafting.

OBJECTIVES: We sought to evaluate the effectiveness of tranexamic acid in off-pump coronary artery bypass grafting surgery, either when used in combination with mechanical cell salvage or when used alone. METHODS: One hundred patients were randomized to either 2 g of tranexamic acid as an intravenous bolus before sternotomy or to placebo. Intraoperative and postoperative cell salvage was used in all patients. The primary end point was early postoperative blood loss (within 4 hours). To evaluate the efficacy of tranexamic acid in isolation, we also performed a meta-analysis of 4 randomized trials identified from a systematic literature search. The primary end point of the meta-analysis was red cell transfusion. RESULTS: In our randomized trial patients in the tranexamic acid group had a significant reduction in early postoperative blood loss, (median difference, 50 mL; 95% confidence interval, 15-100 mL; P < .01); however, there was no reduction in the frequency of blood component transfusion. Patients in the placebo group received a significantly larger volume of autotransfused red cells (median difference, 120 mL; 95% confidence interval, 0-220 mL; P = .02). The meta-analysis demonstrated a significant reduction in red cell transfusions in patients receiving tranexamic acid compared with those receiving placebo (risk ratio, 0.48; 95% confidence interval, 0.24-0.97; P = .041). There was also a reduction in the frequency of any allogeneic blood component transfusion, as well as a highly significant reduction in postoperative blood loss, in patients receiving tranexamic acid (P < .001). CONCLUSIONS: Tranexamic acid reduces blood loss and transfusion requirements in off-pump coronary artery bypass grafting surgery. A reduction in allogeneic blood transfusion was not evident in the presence of perioperative cell salvage. These data support the routine use of tranexamic acid in off-pump coronary artery bypass grafting surgery.

Adult↗
PubMed2000

Cyclosporin A and short-term methotrexate versus cyclosporin A as graft versus host disease prophylaxis in patients with severe aplastic anemia given allogeneic bone marrow transplantation from an HLA-identical sibling: results of a GITMO/EBMT randomized trial.

A randomized trial was carried out comparing cyclosporin A (CsA) and short-term methotrexate (MTX) versus CsA alone for graft versus host disease (GVHD) prophylaxis in patients with severe aplastic anemia (SAA) undergoing allogeneic bone marrow transplantation (BMT) from a compatible sibling. Seventy-one patients (median age, 19 years; range, 4-46 years) were randomized to receive either CsA and MTX or CsA alone for the first 3 weeks after BMT. Subsequently, both groups received CsA orally, with gradual drug reduction until discontinuation 8 to 12 months after BMT. Patients randomized in both arms had comparable characteristics and received the same preparative regimen (ie, cyclophosphamide 200 mg/kg over 4 days). The median time for neutrophil engraftment was 17 days (range, 11-31 days) and 12 days (range, 4-45 days) for patients in the CsA/MTX group and the CsA alone group, respectively (P =.01). No significant difference was observed in the probability of either grade 2, grade 3, or grade 4 acute GVHD or chronic GVHD developing in the 2 groups. The Kaplan-Meier estimates of 1-year transplantation-related mortality rates for patients given either CsA/MTX or CsA alone were 3% and 15%, respectively (P =.07). With a median follow-up of 48 months from BMT, the 5-year survival probability is 94% for patients in the CsA/MTX group and 78% for those in the CsA alone group (P =. 05). These data indicate that the use of CsA with MTX is associated with improved survival in patients with SAA who receive transplants from compatible siblings. (Blood. 2000;96:1690-1697)

Adolescent↗
PubMed1987

Single or multiple doses of metronidazole and ampicillin in elective colorectal surgery. A randomized trial.

A randomized trial including 294 patients was performed to evaluate the prophylactic effect of single vs. multiple doses of antibiotics in elective colorectal surgery. All patients received 1.5 g metronidazole and 3.0 g ampicillin peroperatively and were randomized to: no further prophylactic antibiotic treatment, or ampicillin 1 g X 3 and metronidazole 0.5 g X 3 given intravenously during the second and third postoperative days. Deep wound infection was seen in 9/149 (6 percent) receiving a single dose and in 8/145 (6 percent) receiving multiple doses. No differences were found in the two groups between frequencies of anastomotic dehiscences, intra-abdominal abscesses, sepsis, and pulmonary infections. The two groups were similar according to distribution of sex, age, diagnosis, and type of surgery. A single peroperative dose of metronidazole and ampicillin is a simple and satisfactory antibiotic prophylaxis in elective colorectal surgery.

Adolescent↗
PubMed2005

Using baseline data to design a group randomized trial.

Group randomized trials (GRT) are often designed with relatively little preliminary data available to estimate key parameters. In this paper, however, the opposite situation is considered-very good baseline data are available on the primary outcome of interest. These data can then be used to inform key design and analysis decisions such as (i) should the trial be designed as an unmatched or pair-matched study, or stratified in some other fashion; (ii) is analysis of "change from baseline" preferable to using end-of-study data alone; and (iii) what power might be expected by pursuing these various strategies. The results are applied to a GRT for sexually transmitted diseases prevention in Peru.

Data Interpretation, Statistical↗
PubMed1995

Effects of radiotherapy and surgery in early breast cancer. An overview of the randomized trials.

BACKGROUND: Randomized trials of radiotherapy and surgery for early breast cancer may have been too small to detect differences in long-term survival and recurrence reliably. We therefore performed a systematic overview (meta-analysis) of the results of such trials. METHODS: Information was sought on each subject from investigators who conducted trials that began before 1985 and that compared local therapies for early breast cancer. Data on mortality were available from 36 trials comparing radiotherapy plus surgery with the same type of surgery alone, 10 comparing more extensive surgery with less extensive surgery, and 18 comparing more extensive surgery with less extensive surgery plus radiotherapy. Information on mortality was available for 28,405 women (97.4 percent of the 29,175 women in the trials). RESULTS: The addition of radiotherapy to surgery resulted in a rate of local recurrence that was three times lower than the rate with surgery alone, but there was no significant difference in 10-year survival; among a total of 17,273 women enrolled in such trials, mortality was 40.3 percent with radiotherapy and 41.4 percent without radiotherapy (P = 0.3). Radiotherapy was associated with a reduced risk of death due to breast cancer (odds ratio, 0.94; 95 percent confidence interval, 0.88 to 1.00; P = 0.03), which indicates that, after 10 years, there would be about 0 to 5 fewer deaths due to breast cancer per 100 women. However, there was an increased risk of death from other causes (odds ratio, 1.24; 95 percent confidence interval, 1.09 to 1.42; P = 0.002). This, together with the age-specific death rates, implies, after 10 years, a few extra deaths not due to breast cancer per 100 older women or per 1000 younger women. During the first decade or two after diagnosis, the excess in the rate of such deaths that was associated with radiotherapy was much greater women who were over 60 years of age at randomization (15.3 percent vs. 11.1 percent [339 vs. 249 deaths]) than among those under 50 (2.5 percent vs. 2.0 percent [62 vs. 49 deaths]). Breast-conserving surgery involved some risk of recurrence in the remaining tissue, but no significant differences in overall survival at 10 years were found in the studies of mastectomy versus breast-conserving surgery plus radiotherapy (4891 women), more extensive surgery versus less extensive surgery (4818 women), or axillary clearance versus radiotherapy as adjuncts to mastectomy (4370 women). CONCLUSIONS: Some of the local therapies for breast cancer had substantially different effects on the rates of local recurrence--such as the reduced recurrence with the addition of radiotherapy to surgery--but there were no definite differences in overall survival at 10 years.

Breast Neoplasms↗
PubMed2006

Epidural analgesia associated with low-dose oxytocin augmentation increases cesarean births: a critical look at the external validity of randomized trials.

OBJECTIVE: Randomized controlled trials suggest epidural analgesia (EA) does not increase the frequency of cesarean births compared with opioid analgesia. We analyzed trials comparing EA with opioid analgesia to determine their external validity in contemporary North American practice. STUDY DESIGN: Randomized controlled trials comparing EA with opioid analgesia were identified from the Cochrane database and Medline and included if they reported labor outcomes and management protocols. Labor management was then compared with current obstetric practice determined from surveys of North American teaching maternity units and clinical practice guidelines. RESULTS: Of 19 trials identified, 8 were included. Seven trials used Active Management of Labor protocols that used high-dose oxytocin; each demonstrated no epidural-related increase in cesarean births. One trial that used low-dose oxytocin demonstrated a marked increase in cesarean births. Most large North American obstetric units use low-dose oxytocin. CONCLUSION: Randomized trials showing no effect of EA on cesarean section (CS) rate lack external validity in much of North American practice. The limited data available suggest EA and low-dose oxytocin used together increase the CS rate. Early detection of dystocia and high-dose oxytocin augmentation should be considered for women receiving EA; those delivering in low-dose oxytocin settings should be advised of a probable increase in the likelihood of CS.

Analgesia, Epidural↗
PubMed2004

Sentinel lymph node biopsy versus axillary clearance in operable breast cancer: The RACS SNAC trial, a multicenter randomized trial of the Royal Australian College of Surgeons (RACS) Section of Breast Surgery, in collaboration with the National Health and Medical Research Council Clinical Trials Center.

The aim of the SNAC trial is to determine if sentinel node biopsy (SNB) produces less morbidity and equivalent cancer-related outcomes in comparison with immediate axillary clearance (AC) in women with early breast cancer. The intervention is SNB followed by immediate AC, or SNB followed by AC only if the SNB specimen is positive. This is a multicenter, centrally randomized phase III trial of 1000 women stratified according to age, tumor palpability, lymphatic mapping technique, and center. Accrual rate is 26 women per month; 789 women have been randomized to date. Analysis of the first 150 women indicates good compliance with study treatment and acceptable surgical technique.

Adult↗