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PubMedDate not supplied

Completeness of safety reporting in randomized trials: an evaluation of 7 medical areas.

CONTEXT: Randomized trials with adequate sample size offer an opportunity to assess the safety of new medications in a controlled setting; however, generalizable data on drug safety reporting are sparse. OBJECTIVE: To scrutinize the completeness of safety reporting in randomized trials. DESIGN, SETTING, AND PATIENTS: Survey of safety reporting in 192 randomized drug trials 7 diverse topics with sample sizes of at least 100 patients and at least 50 patients in a study arm (N = 130074 patients). Trial reports were identified from comprehensive meta-analyses in 7 medical areas. MAIN OUTCOME MEASURES: Adequate reporting of specific adverse effects and frequency and reasons for withdrawals due to toxic effects; article space allocated to safety reporting and predictors of such reporting. RESULTS: Severity of clinical adverse effects and laboratory-determined toxicity was adequately defined in only 39% and 29% of trial reports, respectively. Only 46% of trials stated the frequency of specific reasons for discontinuation of study treatment due to toxicity. For these 3 parameters, there was significant heterogeneity in rates of adequate reporting across topics (P =.003, P<.001, and P =.02, respectively). Overall, the median space allocated to safety results was 0.3 page. A similar amount of space was devoted to contributor names and affiliations (P =.16). On average, the percentage of space devoted to safety in the results section was 9.3% larger in trials involving dose comparisons than in those that did not (P<.001) and 3.8% smaller in trials reporting statistically significant results for efficacy outcomes (P =.047). CONCLUSIONS: The quality and quantity of safety reporting vary across medical areas, study designs, and settings but they are largely inadequate. Current standards for safety reporting in randomized trials should be revised to address this inadequacy.

Adverse Drug Reaction Reporting Systems↗

PubMed2006

Multidisciplinary group rehabilitation versus individual physiotherapy for chronic nonspecific low back pain: a randomized trial.

STUDY DESIGN: A randomized trial. OBJECTIVE: To evaluate the effectiveness of a semi-intensive multidisciplinary rehabilitation for patients with chronic low back pain in an outpatient setting. SUMMARY AND BACKGROUND DATA: Systematic reviews have shown that there is strong evidence that intensive multidisciplinary treatment (>100 hours), which includes functional restoration, improves function among chronic patients with low back pain, and moderate evidence that it reduces pain but contradictory evidence regarding improvement of working ability. However, there is paucity of data whether semi-intensive outpatient multidisciplinary rehabilitation in groups is more effective than individual physiotherapy. MATERIALS AND METHODS: A total of 120 women employed as healthcare and social care professionals with nonspecific chronic low back pain were recruited from two occupational healthcare centers. The patients were randomized into two intervention programs. Multidisciplinary rehabilitation (n = 59) was conducted in groups and comprised of physical training, workplace interventions, back school, relaxation training, and cognitive-behavioral stress management methods for 70 hours. The individual physiotherapy (n = 61) included physical exercise and passive treatment methods administered for 10 hours. Main outcome measures were: back pain and sciatic pain intensity, disability, sick leaves, healthcare consumption, symptoms of depression, and beliefs of working ability after 2 years. RESULTS: There were no statistically significant differences between the two treatment groups in main outcome measures just after rehabilitation, at 6-, at 12-, or 24-month follow-up. In both intervention arms, however, the before-and-after comparison showed favorable effects, and the effects were still maintained at 2 years follow-up. CONCLUSIONS: The results of this study indicate that semilight outpatient multidisciplinary rehabilitation program for female chronic low back pain patients does not offer incremental benefits when compared with rehabilitation carried out by a physiotherapist having a cognitive-behavioral way of administering the treatment.

Adult↗

PubMed2005

Prevention of succinylcholine-induced fasciculation and myalgia: a meta-analysis of randomized trials.

Fifty-two randomized trials (5,318 patients) were included in this meta-analysis. In controls, the incidence of fasciculation was 95%, and the incidence of myalgia at 24 h was 50%. Nondepolarizing muscle relaxants, lidocaine, or magnesium prevented fasciculation (number needed to treat, 1.2-2.5). Best prevention of myalgia was with nonsteroidal antiinflammatory drugs (number needed to treat, 2.5) and with rocuronium or lidocaine (number needed to treat, 3). There was a dose-dependent risk of blurred vision, diplopia, voice disorders, and difficulty in breathing and swallowing (number needed to harm, < 3.5) with muscle relaxants. There was evidence of less myalgia with 1.5 mg/kg succinylcholine (compared with 1 mg/kg). Opioids had no impact. Succinylcholine-induced fasciculation may best be prevented with muscle relaxants, lidocaine, or magnesium. Myalgia may best be prevented with muscle relaxants, lidocaine, or nonsteroidal antiinflammatory drugs. The risk of potentially serious adverse events with muscle relaxants is not negligible. Data that allow for a risk-benefit assessment are lacking for other drugs.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed2006

Continuous methimazole therapy and its effect on the cure rate of hyperthyroidism using radioactive iodine: an evaluation by a randomized trial.

BACKGROUND: A randomized clinical trial was performed to clarify whether continuous use of methimazole (MTZ) during radioiodine ((131)I) therapy influences the final outcome of this therapy. DESIGN: Consecutive patients with Graves' disease (n = 30) or a toxic nodular goiter (n = 45) were rendered euthyroid by MTZ and randomized to stop MTZ 8 d before (131)I (-MTZ; n = 36) or to continue MTZ until 4 wk after (131)I (+MTZ; n = 39). Calculation of the (131)I activity included an assessment of the (131)I half-life and the thyroid volume. RESULTS: The 24-h thyroid (131)I uptake was lower in the +MTZ group than in the -MTZ group (44.8 +/- 15.6% vs. 62.1 +/- 9.9%, respectively; P < 0.001). At 3 wk after therapy, no significant change in serum free T(4) index was observed in the +MTZ group (109 +/- 106 vs. 83 +/- 28 nmol/liter at baseline; P = 0.26), contrasting an increase in the -MTZ group (180 +/- 110 vs. 82 +/- 26 nmol/liter; P < 0.001). The number of cured patients was 17 (44%) and 22 (61%) in the +MTZ and -MTZ groups, respectively (P = 0.17). Cured patients tended to have a lower 24-h thyroid (131)I uptake (50.1 +/- 13.8% vs. 56.4 +/- 17.1%; P = 0.09). By adjusting for a possible interfactorial relationship through a regression analysis (variables: randomization, 24- and 96-h thyroid (131)I uptake, type and duration of disease, age, gender, presence of antithyroid peroxidase antibodies, thyroid volume, dose of MTZ), only the continuous use of MTZ correlated with treatment failure (P = 0.006), whereas a low 24-h thyroid (131)I uptake predicted a better outcome (P = 0.006). CONCLUSION: Continuous use of MTZ hinders an excessive increase of the thyroid hormones during (131)I therapy of hyperthyroid diseases. However, such a strategy seems to reduce the final cure rate, although this adverse effect paradoxically is attenuated by the concomitant reduction of the thyroid (131)I uptake.

Adult↗

PubMed2004

Late first-trimester invasive prenatal diagnosis: results of an international randomized trial.

OBJECTIVE: To assess, in a randomized trial, the safety and accuracy of amniocentesis and transabdominal chorionic villus sampling (CVS) performed at 11-14 weeks of gestation, given that this time frame is increasingly relevant to early trisomy screening. METHODS: We compared amniocentesis with CVS from 77 to 104 days of gestation in a randomized trial in a predominantly advanced maternal age population. Before randomization, the feasibility of both procedures was confirmed by ultrasonography, and experienced operators performed sampling under ultrasound guidance; conventional cytogenetic analysis was employed. The primary outcome measure was a composite of fetal loss plus preterm delivery before 28 weeks of gestation in cytogenetically normal pregnancies. RESULTS: We randomized 3,775 women into 2 groups (1,914 to CVS; 1,861 to amniocentesis), which were comparable at baseline. More than 99.6% had the assigned procedure, and 99.9% were followed through delivery. In contrast to previous thinking, in the cytogenetically normal cohort (n = 3,698), no difference in primary study outcome was observed: 2.1% (95% confidence interval 1.5, 2.8) for CVS and 2.3% (95% confidence interval, 1.7, 3.1) for amniocentesis. However, spontaneous losses before 20 weeks and procedure-related, indicated terminations combined were increased in the amniocentesis group (P =.07, relative risk 1.74). We found a 4-fold increase in the rate of talipes equinovarus after amniocentesis (P =.02) overall and in week 13 (P =.03, relative risk = 4.65), but data were insufficient to determine this risk in week 14. CONCLUSION: Amniocentesis at 13 weeks carries a significantly increased risk of talipes equinovarus compared with CVS and also suggests an increase in early, unintended pregnancy loss. LEVEL OF EVIDENCE: I

Abortion, Induced↗

PubMed2000

Randomized trials versus observational studies in adolescent pregnancy prevention.

The objective of this study is to compare the results of randomized trials and observational studies of interventions to prevent adolescent pregnancy. We identified published and unpublished reports through computerized searches of CATLINE, CINAHL, CONFERENCE PAPERS INDEX, DISSERTATION ABSTRACTS ONLINE, EMBASE, ERIC, MEDLINE, NTIS, POPLINE, PsycINFO, and SOCIOLOGICAL ABSTRACTS; manual searches of eight relevant journals; reference lists from primary articles; and contact with content experts. We included randomized trials and observational studies that evaluated the impact of primary prevention interventions including sex education classes, school-based clinics, free-standing clinics, physician/nurse practitioner practice-based service, improved access, and community-based programs on four outcomes: sexual intercourse, birth control use, responsible sexual behavior, or pregnancy in adolescents. One investigator abstracted the data and a second conducted a detailed review of the abstraction. We identified 13 randomized trials and 17 observational studies. We generated estimates of the impact of the interventions separately for males and females for all four outcomes for both observational studies and randomized trials. For six of the eight outcomes the summary odds ratios for the observational studies showed a significant intervention benefit (P<0.05) while the randomized trials did not show a benefit for any outcome in either females or males. The difference between the results of the observational studies and randomized trials was statistically significant in two of the eight outcomes (P<0.05 for initiation of intercourse and pregnancy in females). Observational studies yield systematically greater estimates of treatment effects than randomized trials of adolescent pregnancy prevention interventions. Public policy or individual patient treatment decisions should be based on observational studies only when randomized trials are unavailable and only with careful consideration of possible biases.

Adolescent↗

PubMed1999

Multi-institutional phase II randomized trial of integrated therapy with cisplatin, dacarbazine, vindesine, subcutaneous interleukin-2, interferon alpha2a and tamoxifen in metastatic melanoma. BREMIM (Biological Response Modifiers in Melanoma).

The aim of this study was to evaluate the toxicity and efficacy of a monochemotherapy regimen of dacarbazine (DTIC), tamoxifen , interferon-alpha2a and interleukin-2 (IL-2) and two polychemotherapy regimens of cisplatin, DTIC, vindesine, tamoxifen, interferon-alpha2a with or without IL-2 in patients with metastatic melanoma. Consecutive patients with metastatic melanoma were enrolled in this trial and were randomized to arm A, consisting of DTIC 800 mg/m2 every 21 days, IL-2 9 MIU subcutaneously days 1-5 and 8-12, arm B, consisting of cisplatin 30 mg/m2 days 1-3, DTIC 250 mg/m2 days 1-3 and vindesine 2.5 mg/m2 day 1 every 28 days (CVD), or arm C, consisting of CVD plus IL-2 6 MIU days 1-5 and 8-12 every 28 days. In all three arms Interferon 3 MU subcutaneously three times a week and tamoxifen 20 mg orally were given throughout. Ninety-two patients were included in this study. Patient characteristics in the three groups were well balanced. The three regimens were delivered on an outpatient basis without major toxicity. The toxicities that did occur consisted primarily of flu-like symptoms in the IL-2 arms (A and C) and haematological toxicities in the CVD arms (B and C). No grade IV toxicities were encountered and no treatment-related deaths occurred. The total response rate was 13% in arm A, 35% in arm B and 37% in arm C. The median duration of response was 6 months and the median survival was 11 months. According to this phase II randomized trial polychemoimmunotherapy with CVD has an objective response rate of 35-36%, while monochemoimmunotherapy with DTIC has a response rate of 13%.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2004

Random allocation software for parallel group randomized trials.

BACKGROUND: Typically, randomization software should allow users to exert control over the different aspects of randomization including block design, provision of unique identifiers and control over the format and type of program output. While some of these characteristics have been addressed by available software, none of them have all of these capabilities integrated into one package. The main objective of the Random Allocation Software project was to enhance the user's control over different aspects of randomization in parallel group trials, including output type and format, structure and ordering of generated unique identifiers and enabling users to specify group names for more than two groups. RESULTS: The program has different settings for: simple and blocked randomizations; length, format and ordering of generated unique identifiers; type and format of program output; and saving sessions for future use. A formatted random list generated by this program can be used directly (without further formatting) by the coordinator of the research team to prepare and encode different drugs or instruments necessary for the parallel group trial. CONCLUSIONS: Random Allocation Software enables users to control different attributes of the random allocation sequence and produce qualified lists for parallel group trials.

Algorithms↗

PubMed2005

A priori postulated and real power in cluster randomized trials: mind the gap.

BACKGROUND: Cluster randomization design is increasingly used for the evaluation of health-care, screening or educational interventions. The intraclass correlation coefficient (ICC) defines the clustering effect and be specified during planning. The aim of this work is to study the influence of the ICC on power in cluster randomized trials. METHODS: Power contour graphs were drawn to illustrate the loss in power induced by an underestimation of the ICC when planning trials. We also derived the maximum achievable power given a specified ICC. RESULTS: The magnitude of the ICC can have a major impact on power, and with low numbers of clusters, 80% power may not be achievable. CONCLUSION: Underestimating the ICC during planning cluster randomized trials can lead to a seriously underpowered trial. Publication of a priori postulated and a posteriori estimated ICCs is necessary for a more objective reading: negative trial results may be the consequence of a loss of power due to a mis-specification of the ICC.

Cluster Analysis↗

PubMed2002

Number and size of randomized trials reported in general health care journals from 1948 to 1997.

BACKGROUND: Randomized trials are important for controlling selection biases, and where sufficient numbers of participants are involved, have the potential to yield reliable estimates of treatment effects. METHODS: We investigated trends in the number and size of randomized trials reported in general health care journals from 1948 to 1997. From the handsearching of 18 general health care journals we collected data on the number of reports of randomized trials in each journal per year, and the number of participants in each trial. RESULTS: A total of 5503 reports of trials were identified in 18 general health care journals. More than a third appeared in the British Medical Journal. The peak period for trial reports was the mid 1980s, with more in 1986 than any other year (242). By the mid 1990s the number per year had declined by a third. Trials with fewer than 100 participants accounted for most of the reports (69%). In spite of the overall decline in the number of trial reports, those involving 100 participants or more continued to increase throughout the period studied. CONCLUSIONS: The continued increase in the number of larger trials reported is encouraging, especially if it represents an increase in the size of trials more generally. Further research is needed to determine whether the trends over time identified here are reflective more of trends in the actual conduct of, rather than simply the reporting, of randomized trials.

Humans↗

PubMed1999

Is prophylactic gastrojejunostomy indicated for unresectable periampullary cancer? A prospective randomized trial.

OBJECTIVE: This prospective, randomized, single-institution trial was designed to evaluate the role of prophylactic gastrojejunostomy in patients found at exploratory laparotomy to have unresectable periampullary carcinoma. SUMMARY BACKGROUND DATA: Between 25% and 75% of patients with periampullary cancer who undergo exploratory surgery with intent to perform a pancreaticoduodenectomy are found to have unresectable disease. Most will undergo a biliary-enteric bypass. Whether or not to perform a prophylactic gastrojejunostomy remains unresolved. Retrospective reviews of surgical series and prospective randomized trials of endoscopic palliation have demonstrated that late gastric outlet obstruction, requiring a gastrojejunostomy, develops in 10% to 20% of patients with unresectable periampullary cancer. METHODS: Between May 1994 and October 1998, 194 patients with a periampullary malignancy underwent exploratory surgery with the purpose of performing a pancreaticoduodenectomy and were found to have unresectable disease. On the basis of preoperative symptoms, radiologic studies, or surgical findings, the surgeon determined that gastric outlet obstruction was a significant risk in 107 and performed a gastrojejunostomy. The remaining 87 patients were thought by the surgeon not to be at significant risk for duodenal obstruction and were randomized to receive either a prophylactic retrocolic gastrojejunostomy or no gastrojejunostomy. Short- and long-term outcomes were determined in all patients. RESULTS: Of the 87 patients randomized, 44 patients underwent a retrocolic gastrojejunostomy and 43 did not undergo a gastric bypass. The two groups were similar with respect to age, gender, procedure performed (excluding gastrojejunostomy), and surgical findings. There were no postoperative deaths in either group, and the postoperative morbidity rates were comparable (gastrojejunostomy 32%, no gastrojejunostomy 33%). The postoperative length of stay was 8.5+/-0.5 days for the gastrojejunostomy group and 8.0+/-0.5 days for the no gastrojejunostomy group. Mean survival among those who received a prophylactic gastrojejunostomy was 8.3 months, and during that interval gastric outlet obstruction developed in none of the 44 patients. Mean survival among those who did not have a prophylactic gastrojejunostomy was 8.3 months. In 8 of those 43 patients (19%), late gastric outlet obstruction developed, requiring therapeutic intervention (gastrojejunostomy 7 patients, endoscopic duodenal stent 1 patient; p < 0.01). The median time between initial exploration and therapeutic intervention was 2 months. CONCLUSION: The results from this prospective, randomized trial demonstrate that prophylactic gastrojejunostomy significantly decreases the incidence of late gastric outlet obstruction. The performance of a prophylactic retrocolic gastrojejunostomy at the initial surgical procedure does not increase the incidence of postoperative complications or extend the length of stay. A retrocolic gastrojejunostomy should be performed routinely when a patient is undergoing surgical palliation for unresectable periampullary carcinoma.

Adenocarcinoma↗

PubMed1995

Assertive community treatment: an update of randomized trials.

OBJECTIVE: Results of randomized clinical trials of assertive community treatment for seriously mentally ill patients published between 1990 and 1994 are reviewed to synthesize the state of knowledge about this research and to clarify continuing research directions. METHODS: Randomized trials of interventions that used treatment principles and practices consistent with the Program for Assertive Community Treatment model or close adaptations whose results were published since 1990 were identified by literature searches using MEDLINE and PsychLit and by contact with investigators of ongoing trials. RESULTS: Controlled clinical trials have been conducted with a wide range of severely mentally ill populations, including patients in Great Britain, patients with recent-onset schizophrenia, veterans, dually diagnosed clients, and homeless persons. Methodological improvements in some studies include increased attention to monitoring the experimental and comparison interventions, as well as larger sample sizes and longer duration of the clinical trials than in earlier efficacy trials. Strong positive effects of assertive community treatment on hospital days and on patient and family satisfaction were found. Gains in functional outcomes, such as employment, may require interventions specifically targeted to these outcomes. CONCLUSIONS: Questions about the role of assertive community treatment as time-limited treatment, as an adjunct to other services and treatment, or as a comprehensive and continuous service system for adults with severe mental illness require further research. The growing research base should provide valuable information on costs, outcomes, and indications for assertive community treatment that can be evaluated by policy-makers.

Adult↗

PubMed1999

From randomized trial to community-focused practice.

PURPOSE: To describe the use of findings from a randomized trial--a nursing intervention using telephone contacts to reduce the incidence of low-birth-weight and preterm births--in four community settings in North Carolina, to show that implementing research into practice is important. Low-birth-weight and preterm births are the major cause of high infant mortality in the United States. Rates are highest among African-American women. Telephone intervention as a strategy for preventive health care can be cost effective, reduce low-birth-weight and preterm births in African-American women, and provide a means of health consultation for parents of children age five and under. ORGANIZING FRAMEWORK: Four community programs are discussed in relation to five phases of implementing and sustaining research in communities: research, transfer, transition, regeneration, and empowerment. Modification from the original research, bonuses, and barriers are described for each program. METHODS: The randomized trial was conducted from 1990-1995. Randomized trial data and data for subsequent projects were collected from telephone interviews and health care records from 1994-1998. A successful adaptation was made from the original randomized trial to the four programs by (a) educating the staff for each program about the methods and findings in the original research, and (b) working with program staff to make appropriate modifications for each site. CONCLUSIONS: Findings from a randomized trial can be used in a variety of settings. By working together, researchers and community-health nurses can integrate research findings into community-health nursing practice.

Black People↗

PubMed2000

Experimental design and methods for school-based randomized trials. Experience from the Hutchinson Smoking Prevention Project (HSPP).

Nonadherence to accepted design principles for randomized trials has been a limitation of school-based intervention research. Designed to overcome these limitations, the Hutchinson Smoking Prevention Project (HSPP) is a 15-year randomized trial to determine the extent to which a school-based (grades 3-12) tobacco use prevention intervention can deter youth tobacco use throughout and beyond high school. This paper presents the HSPP experimental design, together with methods for its implementation, and an evaluation of the degree to which HSPP has adhered to principles of randomized trials. Results from the experimental design and its conduct include (1) a recruitment rate of 97.6% (40 of 41 targeted school districts), (2) full and active participation for the trial's duration by 100% of the 40 school districts recruited, (3) implementation by virtually all teachers (99%+), with 86% implementation fidelity, and (4) outcome determination for 94.3% (7910) of 8388 original study participants identified 12 years previously at baseline. The high degree of rigor achieved by the HSPP experimental design ensures confidence in the trial's soon-to-be available intervention effectiveness results. Equally important, for future school-based trials, the HSPP design and its execution have illustrated that school-based research can adhere to the principles of rigorous randomized trials, with high rates of implementation, and very high rates of recruitment, maintenance, and follow-up of study participants, even for studies with decade-long follow-up periods. Rigor in school-based trials can be achieved through a combination of (1) commitment to the principles of randomized trials, (2) attention to the special challenges of trials specific to the school setting, (3) adoption and meticulous execution of proven methods for trial conduct, and (4) establishment at the outset of principles for maintaining positive collaborative relationships with participating school districts for the duration of the trial. These findings are important in light of the great potential for using the nation's schools to access youth for health promotion/risk-factor prevention.

Adolescent↗

PubMed1990

Recombinant leukocyte interferon alpha-2a and medroxyprogesterone in advanced renal cell carcinoma. A randomized trial.

In a randomized study of advanced renal cell carcinoma 60 patients were allocated to treatment with either recombinant interferon alpha-2a or medroxyprogesterone acetate. Correlation between the dose of interferon alpha-2a and plasma-concentration indicated linear kinetics. Survival was similar in the two treatment groups. Only one complete and one partial response were seen in the interferon group and only one complete response in the medroxyprogesterone group, indicating a low therapeutic potential of both interferon and medroxyprogesterone. Interferon influenced the serum liver enzyme levels; increased transaminases were seen in 17 patients treated with interferon but in only four patients in the medroxyprogesterone group. Two patients had very high serum liver-enzyme levels concomitant with intolerable tiredness, in both patients the symptoms disappeared and the enzymes normalized after discontinuation of the interferon treatment. Antibodies to interferon developed frequently in patients receiving high dose oligomeric interferon therapy but rarely in patients receiving low dose monomeric interferon treatment.

Adult↗

PubMed2001

Bayesian methods of analysis for cluster randomized trials with binary outcome data.

We explore the potential of Bayesian hierarchical modelling for the analysis of cluster randomized trials with binary outcome data, and apply the methods to a trial randomized by general practice. An approximate relationship is derived between the intracluster correlation coefficient (ICC) and the between-cluster variance used in a hierarchical logistic regression model. By constructing an informative prior for the ICC on the basis of available information, we are thus able implicitly to specify an informative prior for the between-cluster variance. The approach also provides us with a credible interval for the ICC for binary outcome data. Several approaches to constructing informative priors from empirical ICC values are described. We investigate the sensitivity of results to the prior specified and find that the estimate of intervention effect changes very little in this data set, while its interval estimate is more sensitive. The Bayesian approach allows us to assume distributions other than normality for the random effects used to model the clustering. This enables us to gain insight into the robustness of our parameter estimates to the classical normality assumption. In a model with a more complex variance structure, Bayesian methods can provide credible intervals for a difference between two variance components, in order for example to investigate whether the effect of intervention varies across clusters. We compare our results with those obtained from classical estimation, discuss the relative merits of the Bayesian framework, and conclude that the flexibility of the Bayesian approach offers some substantial advantages, although selection of prior distributions is not straightforward.

Bayes Theorem↗

PubMed1995

Surgery for Obesity- An Update of a Randomized Trial.

BACKGROUND: A prospective, randomized trial comparing vertical banded gastroplasty (VBG) and gastric bypass (GB) was performed on 106 patients between 1987 and 1990. METHODS AND RESULTS: Failures of these two operations (manifested by failure to lose weight, late weight gain or intolerance of adequate oral intake) were treated by means of a third operation, isolated gastric bypass (IGB), in which the small gastric pouch was isolated from the gastric fundus. The latter operation was significantly better than VBG or GB and achieved a 63% success rate, i.e. body mass index (BMI) < 35 kg m(2) and less than 50% excess weight. During the year following this trial an additional 54 patients underwent IGB. When this operation was performed for morbid obesity and was the Initial procedure, 96% of the patients achieved a successful result. If IGB was performed as a revision procedure or for super obesity (BMI > 50 kg m(2)), the success rate was 63% with 100% follow-up at 40 months. Major morbidity occurred in six of the 160 patients who underwent 195 operations (the trial period and subsequent year). There were no deaths and follow-up was 98%. CONCLUSIONS: The ideal gastric operation based on this study emphasizes the following requirements: a small pouch (< 15 ml) totally separated from the stomach, a pouch not dependent on staples, placed in the dependent position to prevent stasis, constructed without foreign material and with an anastomosis which permits ingestion of solid food.

Journal Article↗

PubMed2002

Magnitude of the placebo effect in randomized trials of antiepileptic agents.

Placebo-controlled randomized trials ideally produce unbiased estimates of the treatment effect after accounting for nonpharmacological effects (regression to the mean, Hawthorne, and placebo effects). Recognizing that the magnitude of these effects may help understand why investigators need to control for them, we sought to measure this magnitude. We reviewed published meta-analyses of randomized, placebo-controlled add-on trials of antiepileptic medications versus placebo, included in the Cochrane Library. In randomized trials of antiepileptic agents for epilepsy, 9.3-16.6% of patients in the placebo arm had a >50% reduction in seizure frequency. This effect represents 20-50% of the effect observed with active agents. Because patients with epilepsy in the placebo arm of randomized trials experience a large clinical benefit due to nonpharmacological effects, randomized controlled trials are necessary to gauge the true magnitude of the treatment effect of new antiepileptic agents.

Journal Article↗