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Results for “multicenter study”

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PubMed1989

Use of external shock-wave lithotripsy and adjuvant ursodiol for treatment of radiolucent gallstones. A national multicenter study.

A prospective multicenter trial was performed to evaluate the use of external shockwave lithotripsy (ESL) and adjuvant medical therapy for the treatment of gallstones. A Medstone STS lithotripter was used together with ursodiol. Two hundred twenty-three patients were treated under general anesthesia (75%) or with intravenous analgesia (25%). Initial treatments were on an inpatient basis, but as centers gained experience, outpatient treatments became more common. Stone fragmentation and clearance were greatest in patients with solitary gallstones less than 2 cm in diameter. In this group of patients, stone fragmentation occurred in 97% of patients, and the cumulative stone-free rates at three and six months were 54% and 90%, respectively. These results indicate that fragmentation of gallstones can be achieved by a dry shock-wave lithotripter and that stone clearance is induced more rapidly by external shock-wave lithotripsy and adjuvant ursodiol therapy than by ursodiol therapy alone.

Adult↗

PubMed1991

[Whole-body MRT studies--the results of the "Multicenter study on the evaluation of magnetic resonance tomography"].

In a nation-wide multicentre study, the use of MRI was examined in its clinical context and in relation to other imaging methods and as a routine examination. It was found that examinations of the brain and spine were predominant. MRI is accurate for certain problems affecting the extremities, the pelvis and the liver. The findings also show that there are still technical limitations. A high degree of accuracy can only be obtained if there is adequate information concerning individual problems. Technical limitations include the frequent appearance of artifacts. In its present state, MRI can only supply additional information, concerning the trunk only, in certain situations. The study also outlines the development of MRI and the role of other conventional diagnostic procedures.

Evaluation Studies as Topic↗

PubMed1997

[Psychopathological evaluation of children and adolescents in 4 child and adolescent psychiatry referral groups--a multicenter study].

Goal of the multicenter study with the Clinical Assessment Scale of Child and Adolescent Psychopathology (CASCAP) in a sample of N = 5027 patients from the inpatient and outpatient clinics of psychiatry and psychotherapy of childhood and adolescence of the universities of Berlin (Virchow Clinic), Frankfurt, Cologne and Zurich is the comparison of the clinical populations of these institutions with respect to single symptoms, to symptom scales and to the supreme level of aggregation, the clinical diagnoses according to ICD 10. On the level of diagnoses similar distributions can be found in the centers, but there are also significant differences between the centers. This differences can be found again also on the level of symptom scales and single symptoms, though the deviations are comparatively low.

Adolescent↗

PubMed1995

[Amlodipine in long-term treatment of mild and moderate hypertension. A multicenter study].

METHOD: An open, multicenter study was conducted to investigate the antihypertensive efficacy and safety of amlodipine in the long-term treatment of patients with mild to moderate essential hypertension of a period of 178 weeks (3.4 years). RESULTS: 92 of the 110 patients participating in the study received amlodipine treatment throughout the total study period, with 77 patients on amlodipine monotherapy (mean daily dose 6.3 mg), and 15 patients on combination antihypertensive therapy including amlodipine (mean daily dose 7.1 mg). After 8 weeks of treatment the diastolic target blood pressure of < or = 90 mmHg was achieved in 86 out of 92 patients (93.5%). The mean diastolic blood pressure reduction was retained throughout the treatment, both in patients receiving monotherapy and those on combination therapy. The incidence of adverse events was highest during the first 12 weeks of treatment (30.0%); after another 54 weeks it dropped to 18.1%, and to 7.3% during the last 112 weeks. The side effects reported most frequently were headaches and edema. CONCLUSION: These results indicate that amlodipine effects sustained reduction in diastolic blood pressure over a period of more than 3 years in patients with mild to moderate hypertension.

Adult↗

PubMed1995

Multicenter study of lipoprotein(a) and apolipoprotein(a) phenotypes in patients with end-stage renal disease treated by hemodialysis or continuous ambulatory peritoneal dialysis.

Numerous studies have investigated lipoprotein(a) (Lp(a)) plasma concentrations in patients with ESRD, a patient group with an enormous risk for atherosclerosis. The reported differences in Lp(a) between controls and patients vary from a decrease of 49% to an increase of more than 1,000%. However, data are not consistent, mostly because of problems with statistical analysis, and only limited data are available for patients treated by continuous ambulatory peritoneal dialysis (CAPD). To estimate the significance of Lp(a) in ESRD and to demonstrate the statistical pitfalls concerning Lp(a) in case-control studies, a large multicenter study including 702 patients treated by either hemodialysis (HD) (N = 534) or CAPD (N = 168) was conducted, and results were compared with results from 256 healthy controls. Both patient groups showed significantly elevated Lp(a) levels in comparison with controls: 23.4 +/- 25.0 mg/dL (P < 0.005; HD) and 34.6 +/- 38.4 mg/dL (P < 0.0001; CAPD) versus 18.4 +/- 22.8 mg/dL (controls). CAPD patients showed significantly higher Lp(a) values than did patients treated by HD (P < 0.001). The difference between the two treatment groups possibly reflects an overproduction of Lp(a) to compensate for protein losses in CAPD patients. Both treatment groups included significantly more patients with Lp(a) values greater than the 75th percentile (25.6 mg/dL) of the control group (33.9 and 41.7% for HD and CAPD, respectively; P < 0.005). The higher Lp(a) values in patients were not explained by differences in isoform frequencies and the increase in Lp(a) was apolipoprotein(a) type specific: only patients with high-molecular-weight apolipoprotein(a) isoforms showed a significant elevation in Lp(a) levels. The increased plasma concentrations of Lp(a) may contribute to the high risk for atherosclerosis in ESRD, especially in patients treated by CAPD. Finally, it is believed that small sample sizes are responsible for the diverging results in Lp(a) literature.

Adult↗

PubMed1993

Multicenter study of standardization of cell counting. Haemapheresis Scientific Workshop Group of DGTI.

Multicenter studies on cell separators give valid data (which can be compared between the different centers) only if the cell counting methods are uniform. This has to be demonstrated by ring studies or multicenter counting studies. Twelve apheresis centers involved in a multicenter study for the evaluation of the Fresenius AS 104 cell separator participated in such a ring study from July 1990 to July 1991. The twelve participating centers split into three significantly different groups according to the platelet counts in the platelet concentrates and a calculated pseudo extraction efficiency. No differences could be found in the white and red blood cell counts. No mailing effect--or time effect--and no personal effect could be found in the reference center.

Blood Component Removal↗

PubMed1989

Sultamicillin versus amoxicillin in the treatment of tonsillitis and pharyngitis: a European multicenter study.

In this multicenter open, comparative study, 135 patients were treated with sultamicillin (67 subjects; 500 mg every 12 h) or amoxicillin (68 subjects; 500 mg every 8 h) for 10 d. Of the pathogens isolated pre-treatment, 24 of 29 (including 4 of 6 resistant strains) in the sultamicillin group were eradicated at the end of treatment, as were 17 of 22 in the amoxicillin group. At follow-up, the figures were 17 of 25 and 16 of 19, respectively. Clinical success was achieved in 55 of 55 sultamicillin and 40 of 43 amoxicillin patients at the end of treatment, and in 40 of 42 and 29 of 31, respectively, at follow-up. Overall success was recorded in 20 of 25 and 15 of 23 sultamicillin, and 14 of 19 and 13 of 17 amoxicillin patients at the two assessments. Side effects were reported for 21 sultamicillin patients, 1 of whom withdrew because of diarrhea, and 15 amoxicillin patients, 4 of whom withdrew because of rash. One sultamicillin and 4 amoxicillin patients developed minor abnormalities in laboratory safety parameters.

Adolescent↗

PubMed1995

Oropharyngeal candidiasis in immunocompromised children: a randomized, multicenter study of orally administered fluconazole suspension versus nystatin. The Multicenter Fluconazole Study Group.

OBJECTIVE: To compare the efficacy, safety, and tolerance of fluconazole suspension versus nystatin in the treatment of oropharyngeal thrush in immunocompromised children. DESIGN: Multicenter, randomized, observer-masked trial. SETTING: Thirty-two centers participated, including hospitals and ambulatory care clinics. PATIENTS: We enrolled 182 immunocompromised infants and children, ages 5 months to 14 years, with signs of oral thrush and presence of yeasts on potassium hydroxide- or gram-stained preparations. Subjects were randomly assigned to receive a single daily dose of fluconazole suspension, 2 to 3 mg/kg per day, or nystatin, 400,000 units four times daily for 14 days; 159 patients, who had culture confirmation of thrush and received at least 7 days of study drug, were evaluated for efficacy; all patients were evaluated for safety. RESULTS: Clinical cure was demonstrated in 91% of the subjects in the fluconazole group and 51% of the subjects in the nystatin group (p < 0.001), and eradication of the organism cultured at entry occurred in 76% and 11% (p < 0.001), respectively. Gastrointestinal conditions developed in six patients who received fluconazole and in three who received nystatin; two fluconazole recipients were subsequently withdrawn from the study. Laboratory abnormalities occurred with equal frequency in both groups. Clinical relapse rates were similar in both groups at 2 weeks (18% and 24% for fluconazole and nystatin, respectively) and 1 month (28% and 27%, respectively) after the completion of study drug. CONCLUSIONS: Fluconazole suspension is more effective than nystatin in the treatment of thrush in immunocompromised children. Both regimens were well tolerated.

Administration, Oral↗

PubMed1998

Early results of a prospective multicenter study on 500 consecutive cases of laparoscopic colorectal surgery. Laparoscopic Colorectal Surgery Study Group (LCSSG).

BACKGROUND: Prospective randomized multicenter studies comparing laparoscopic with open colorectal surgery are not yet available. Reliable data from prospective multicenter studies involving consecutive patients are also lacking. On the basis of the personal caseloads of specialized surgeons or of retrospective analyses, it is difficult to judge the true effectiveness of this new technique. This study aims to investigate the results of laparoscopic colorectal surgery in consecutive patients operated on by unselected surgeons. METHODS: This observational study was begun August 1, 1995, in the German-speaking part of Europe (Germany and Austria) and 43 centers initially agreed to participate. All consecutive cases were documented. All data were rendered anonymous. Analysis was performed on an intention-to-treat basis. The study committee was blinded to the participating center. RESULTS: By the end of the 1st year, 500 patients (M:F ratio 0.83, mean age 62.9 years) had been treated by 18 centers; 269 operations were performed for benign indications and 231 for cancer (palliative and curative). Most operations were done on the distal colon or rectum. An anastomosis was performed in 84%, with an overall leakage rate of 5.3% (colon 3.6% and rectum 11.8%), which required surgical reintervention in 1.7%. The mean operating time was 176 min and showed a decreasing tendency over the period under study. The conversion rate was 7.0% and the overall complication rate 21.4%. The reoperation rate was 6.6%; the most common cause was bleeding. There was one ureteral lesion (0.2%), but urinary tract infections were fairly common (4.8%). A postoperative pneumonia was diagnosed in 1.6% of the cases. No thromboembolic complications were reported. The 30-day mortality rate was 1.4% and overall hospital mortality 1.8%. CONCLUSIONS: Laparoscopic colorectal operations are still rare (about 1% of all colorectal operations in Germany). Laparoscopic procedures are more common on the left colon and rectum than on the right colon. The surgical complication rate is acceptable, comparable with rates reported by others for open surgery. Cardiopulmonary and thromboembolic complications were rarely seen. Mortality and surgical morbidity rates do not differ significantly among participating centers. A learning curve, reflected by a shortening of the operating time and a somewhat lower conversion rate, was observed over the observation period.

Aged↗

PubMed1993

Improving intensive care: observations based on organizational case studies in nine intensive care units: a prospective, multicenter study.

OBJECTIVE: To examine organizational practices associated with higher and lower intensive care unit (ICU) outcome performance. DESIGN: Prospective multicenter study. Onsite organizational analysis; prospective inception cohort. SETTING: Nine ICUs (one medical, two surgical, six medical-surgical) at five teaching and four nonteaching hospitals. PARTICIPANTS: A sample of 3,672 ICU admissions; 316 nurses and 202 physicians. MATERIALS AND METHODS: Interviews and direct observations by a team of clinical and organizational researchers. Demographic, physiologic, and outcome data for an average of 408 admissions per ICU; and questionnaires on ICU structure and organization. The ratio of actual/predicted hospital death rate was used to measure ICU effectiveness; the ratio of actual/predicted length of ICU stay was used to assess efficiency. MEASUREMENTS AND MAIN RESULTS: ICUs with superior risk-adjusted survival could not be distinguished by structural and organizational questionnaires or by global judgment following on-site analysis. Superior organizational practices among these ICUs were related to a patient-centered culture, strong medical and nursing leadership, effective communication and coordination, and open, collaborative approaches to solving problems and managing conflict. CONCLUSIONS: The best and worst organizational practices found in this study can be used by ICU leaders as a checklist for improving ICU management.

Critical Care↗

PubMed1996

Prospective, multicenter study of spinal cord stimulation for relief of chronic back and extremity pain.

STUDY DESIGN: This prospective, multicenter study was designed to investigate the efficacy and outcome of spinal cord stimulation using a variety of clinical and psychosocial outcome measures. Data were collected before implantation and at regular intervals after implantation. This report focuses on 70 patients who had undergone 1 year of follow-up treatment at the time of data analysis. OBJECTIVES: To provide a more generalizable assessment of long-term spinal cord stimulation outcome by comparing a variety of pain and functional/quality-of-life measures before and after management. This report details results after 1 year of stimulation. SUMMARY OF BACKGROUND DATA: The historically diverse methods, patient selection criteria, and outcome measures reported in the spinal cord stimulation literature have made interpretation and comparison of results difficult. Although short-term outcomes are generally consistent, long-term outcomes of spinal cord stimulation, as determined by prospective studies that assess multidimensional aspects of the pain complaint among a relatively homogeneous population, are not well established. METHODS: Two hundred nineteen patients were entered at six centers throughout the United States. All patients underwent a trial of stimulation before implant of the permanent system. Most were psychologically screened. One hundred eighty-two patients were implanted with a permanent stimulating system. At the time of this report, complete 1-year follow-up data were available on 70 patients, 88% of whom reported pain in the back or lower extremities. Patient evaluation of pain and functional levels was completed before implantation and 3, 6, 12, and 24 months after implantation. Complications, medication usage, and work status also were monitored. RESULTS: All pain and quality-of-life measures showed statistically significant improvement during the treatment year. These included the average pain visual analogue scale, the McGill Pain Questionnaire, the Oswestry Disability Questionnaire, the Sickness Impact Profile, and the Back Depression Inventory. Overall success of the therapy was defined as at least 50% pain relief and patient assessment of the procedure as fully or partially beneficial and worthwhile. Using this definition, spinal cord stimulation successfully managed pain in 55% of patients on whom 1-year follow-up is available. Complications requiring surgical intervention were reported by 17% (12 of 70) of patients. Medication usage and work status were not changed significantly. CONCLUSIONS: This prospective, multicenter study confirms that spinal cord stimulation can be an effective therapy for management of chronic low back and extremity pain. Significant improvements in many aspects of the pain condition were measured, and complications were minimal.

Adult↗

PubMed1994

A multicenter study on hip fractures in Thailand.

The present study is a multicenter study on hip fractures aimed at estimating the incidence among Thais. It also describes treatment modalities, associated medical care costs, complications, outcome of orthopedic care, length of stay in hospitals and duration of delay in seeking orthopedic care after occurrence of fractures. An extremely low hip fracture incidence of 7.05 per 100,000 population was found. Hip fracture was shown to increase steeply with age. An average of 26.44 days of delay in seeking orthopedic care following occurrence of hip fractures was reported. In contrast to the belief in Western countries that almost all hip fractures will seek orthopedic care, 7.8 per cent of these Thai cases denied orthopedic care during admission to hospitals. Median of charge to patients was 11205.00 baht, over one fourth of the national income per capita (36,563).

Age Distribution↗

PubMed1995

Transvaginal ultrasonography of the endometrium in women with postmenopausal bleeding--a Nordic multicenter study.

OBJECTIVE: The purpose of this study was to use transvaginal ultrasonographic measurements to find the thickness of the endometrium below which the risk of endometrial abnormality in women with postmenopausal bleeding is low. STUDY DESIGN: This multicenter study was carried out at eight clinics in four Nordic countries. The study included 1168 women with postmenopausal bleeding scheduled for curettage Before the curettage was performed, the thickness of the endometrium was measured with transvaginal ultrasonography. The measurement included both endometrial layers (double-layer technique). The transvaginal ultrasonographic measurement was compared with the histopathologic diagnosis of the curettage specimens. RESULTS: In women with atrophic endometrium the mean endometrial thickness (+/- SD) was 3.9 +/- 2.5 mm. The corresponding figures for women with endometrial cancer were 21.1 +/- 11.8 mm. No malignant endometrium was thinner than 5 mm. In 30 women (2.8%) it was not possible to measure the thickness of the endometrium; one of these women had endometrial cancer. The 95% confidence limit for the probability of excluding endometrial abnormality was 5.5% when the endometrial thickness was < or = 4 mm as measured by transvaginal ultrasonography. CONCLUSION: The risk of finding pathologic endometrium at curettage when the endometrium is < or = 4 mm as measured by transvaginal ultrasonography is 5.5%. Thus in women with postmenopausal bleeding and an endometrium < or = 4 mm it would seem justified to refrain from curettage.

Adult↗

PubMed1993

Multicenter study of single-dose and multiple-dose fleroxacin versus ciprofloxacin in the treatment of uncomplicated urinary tract infections.

The clinical efficacy and safety of single-dose and multiple-dose fleroxacin were assessed and compared with those of ciprofloxacin in women with uncomplicated urinary tract infection (UTI) in this clinical study. This multicenter, randomized, double-blind, prospective study compared single-dose therapy with fleroxacin, 400 mg, with 7-day courses of fleroxacin, 200 mg once a day, and ciprofloxacin, 250 mg twice a day, in the treatment of uncomplicated symptomatic UTI in women at 18 centers in the United States. Of 961 patients enrolled, 316 were in the fleroxacin single-dose group, 321 in the fleroxacin 7-day group, and 324 in the ciprofloxacin group. Of these patients, 943 met the criteria for inclusion in the safety analysis and 556 met those for inclusion in the efficacy analysis. Bacteriologic cure rates at 5-9 days after therapy in patients evaluable for efficacy were 88%, 96%, and 96% in the single-dose fleroxacin group, 7-day fleroxacin group, and 7-day ciprofloxacin group, respectively (p < 0.05). Clinical cures occurred in 93.6%, 97.2%, and 98% of the groups, respectively (difference not significant). At 4-6 weeks after therapy, the rates of bacteriologic cure in the single-dose fleroxacin group, 7-day fleroxacin group, and 7-day ciprofloxacin group were 91%, 89%, and 93%, respectively (difference not significant). Adverse events were similar to those with other new quinolones and comparable among the treatment groups. Insomnia was more frequent in patients who received fleroxacin. Fleroxacin and ciprofloxacin as multidose regimens are similarly safe and effective in the treatment of uncomplicated UTI in women. Single-dose fleroxacin achieved a clinical response rate comparable to that achieved by the multiple-dose regimens, whereas its bacteriologic eradication rate was inferior.

Adolescent↗

PubMed1999

Probucol for treatment of hyperlipidemia in persistent childhood nephrotic syndrome. Report of a prospective uncontrolled multicenter study.

In a prospective, uncontrolled multicenter study, we have evaluated the effects of probucol on hyperlipidemia, proteinuria, and glomerular filtration rate (GFR) in hyperlipidemic children with persistent nephrotic syndrome. Probucol was started for a total of 12 weeks in 8 children and for 24 weeks in 14 children. Lipoprotein profiles, serum malondialdehyde (MDA) levels, proteinuria, renal function, and electrocardiogram were monitored every 4 weeks. Side effects were recorded by questionnaire. Treatment was completed by 7 of 8 patients for 12 weeks and by 7 of 14 children for 24 weeks. After 12 weeks, the mean serum concentrations of triglycerides (-15%), total cholesterol (-25%), very low-density lipoprotein-cholesterol (-27%), low-density lipoprotein-cholesterol (-23%), and high-density lipoprotein-cholesterol (-24%), as well as apolipoprotein (apo) A-I (-19%), apo B (-21%), and MDA (-32%) were reduced. The positive effects of probucol on the lipoprotein profile persisted over 24 weeks; however, there was no significant effect on either proteinuria or GFR. In conclusion, probucol had beneficial effects on lipoproteins and lipid peroxidation, but improved neither proteinuria nor GFR. The drug was generally tolerated well, but had to be discontinued because of a prolonged QT interval in 4 of 22 patients.

Adolescent↗

PubMed1989

Clinical experience with ciprofloxacin: analysis of a multicenter study.

The authors report a multicenter study of 19 patients treated with ciprofloxacin (mean daily dosage, 972 mg per day; mean duration of treatment, 8.5 days) for a variety of infections, ten microbiologically proven. Of these, bacteriologic cure equaled 70%, and improvement 30%. Overall, clinical cure equaled 73.7%, while improvement was 15.8%. No infections were classified as chronic. One adverse reaction was noted; a case of severe vomiting classified as related definitely to ciprofloxacin therapy. The patient discontinued therapy.

Adolescent↗

PubMed1987

Efficacy of nifedipine gastrointestinal therapeutic system in combination with beta blockers in the management of exertional angina. A multicenter study of 54 patients.

This multicenter study assessed the efficacy of a new formulation of nifedipine in 54 patients with stable angina pectoris receiving beta-blocker therapy. This once-daily preparation of nifedipine was administered in double-blind fashion in doses of 30, 60, and 90 mg. All patients experienced pain-limited exercise at placebo baseline treadmill testing. Eight hours post-dose exercise testing resulted in a significant increase in time to onset of angina for all three dose levels of nifedipine but not for placebo. Exercise testing 24 hours after dosing showed significant improvement in time to angina and total exercise time for patients receiving 60-mg and 90-mg doses but not for the 30-mg or placebo categories. These preliminary results suggest that this new formulation of nifedipine is beneficial when added to stable doses of a beta blocker in patients in whom angina is still exhibited during exercise testing.

Adrenergic beta-Antagonists↗

PubMed1986

The prognosis of transient global amnesia. Results of a multicenter study.

In a Danish multicenter study, 74 patients 20 to 75 years of age (mean age, 58.8 years) with transient global amnesia (TGA) without accompanying major neurological signs were studied. Over a follow-up period ranging from seven to 210 months (mean, 66.6 months) the observed rates of death and cerebrovascular morbidity were similar to those expected in the Danish population, matched for age and sex. Sixteen patients (22%) had further TGAs occurring one month to nine years after the original episode; the mean annual recurrence rate was 4.7%. We concluded that TGA without associated major neurological deficits is a benign clinical phenomenon, probably caused by a functional cerebral disturbance unrelated to cerebrovascular disease in general. Furthermore, the observed temporal pattern of recurrence suggests that, although TGA is in principle a recurrent disorder, the annual risk of recurrence is so low that most of the elderly patients are likely to experience only one attack.

Adult↗