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PubMed1991

A double blind, randomised, multicentre comparison of two doses of intravenous iloprost in the treatment of Raynaud's phenomenon secondary to connective tissue diseases.

OBJECTIVE: To compare low (0.5 ng/kg/min) and standard dose (2 ng/kg/min) iloprost (a stable carbacyclin analogue of prostacyclin) in patients with Raynaud's phenomenon secondary to connective tissue disorders. DESIGN: Double blind, random allocation, three six hour infusions on consecutive days. Follow up period eight weeks. SETTING: Rheumatology units, five teaching hospitals. PATIENTS: 55 Patients with Raynaud's phenomenon (greater than seven attacks per week), 32 secondary to well documented classical progressive systemic sclerosis (American Rheumatism Association criteria), 11 CREST syndrome, 5 mixed connective tissue disease, 1 rheumatoid arthritis, 1 Sjögren's syndrome, 1 childhood dermatomyositis, and 4 abnormal nailfold capillaroscopy and antibody profiles but no definite diagnosis. INTERVENTIONS: All other treatment for Raynaud's phenomenon was discontinued two weeks before entry. 28 Patients were randomly allocated to receive the low dose, 27 the standard dose. Differing dilutions allowed infusion rates to be started at 10 ml/h with increments of 10 ml/h every 15 minutes until infusion rates reached 0.5 ng/kg/min and 2 ng/kg/min respectively. MAIN OUTCOME MEASURE(s)--Reduction in frequency, duration, and severity of attacks of Raynaud's phenomenon. Assessment of ulcer and ischaemic lesion healing. RESULTS: Both dosage regimens were equally effective in reducing severity, frequency, and duration of Raynaud's attacks. Ulcer healing occurred to similar degree in both treatment groups (standard dose 44%, low dose 39%). Low dose was associated with significantly fewer side effects. CONCLUSIONS: Both dosage regimens reduce severity of Raynaud's phenomenon and encourage ulcer healing. Low dose was associated with fewer side effects and was better tolerated by the patients.

Adult↗

PubMed1992

Effects of lorazepam on psychomotor performance: a comparison of independent-groups and repeated-measures designs.

The purpose of this study was to compare the sensitivity to the effects of lorazepam (2.5 mg) of a design using independent groups (random allocation of subjects to either a placebo or a lorazepam treatment) with a repeated-measures design (subjects tested both before and after lorazepam treatment). With both designs, it was possible to demonstrate significant and equal effects of lorazepam in tests based upon speed of responding: Lorazepam significantly increased simple reaction time and significantly decreased performance in number cancellation and symbol copying tasks. The independent-groups design was more sensitive (i.e., showed effects at a higher level of significance) to the lorazepam-induced impairment in episodic memory, as assessed in a picture recognition task, and to the lorazepam-induced impairment in a word completion task. Comparisons between the two control condition scores indicated that there were unlikely to be significant group differences with random allocation of a relative homogeneous group of volunteers, such as medical students. While either design would be appropriate for homogeneous populations, for a heterogeneous clinical population where groups cannot be matched the repeated-measures design would be preferable.

Adult↗

PubMed1992

Alternatives to randomization in surgical studies.

The purpose of randomization is to provide unbiased estimates of treatment effects and valid probability statements for hypothesis tests in comparative studies. Difficulties with randomized allocation of patients in surgical studies include: patient selection--due to protocol limitations, possible changes in referral patterns, the need for patient consent, and physician co-operation; disruption of the patient-physician relationship; static protocol not responsive to changes as surgical skill evolves and experience regarding patient selection is acquired; the larger number of patients required causes a longer study and more patients receiving what may be a worse therapy. Moreover, for evaluating a new heart valve, the primary purpose should be estimation rather than comparison with a current device. This can be accomplished faster, in a more generalizable way and with more concern for patient care by using non-randomized comparison groups.

Ethics, Medical↗

PubMed1992

Relationship between the onset of oestrus, the preovulatory surge in luteinizing hormone and ovulation following oestrous synchronization and superovulation of farmed red deer (Cervus elaphus).

The timing of ovulation relative to the onset of oestrus and the preovulatory surge in luteinizing hormone (LH) was studied in red deer following treatments to synchronize oestrus and induce either a monovulatory or superovulatory response. Mature hinds (n = 36) were allocated randomly to two mating groups (n = 16 + 20), with respective treatments staggered by 4 weeks during the 1990 rut (March-April). Each hind was treated with an intravaginal controlled internal drug releasing (CIDR)-type S device for 14 days. Treatments to induce a monovulatory response included CIDR device alone (treatment A; n = 4 + 8) and additional injection of 200 iu pregnant mares' serum gonadotrophin (PMSG) at device removal (treatment B; n = 4 + 4). Treatments to induce a superovulatory response included injections of 200 iu PMSG and 0.5 units ovine follicle-stimulating hormone (FSH) at about time of removal of CIDR devices (treatment C; n = 4 + 4) and further treatment with gonadotrophin-releasing hormone (GnRH) analogue 18 h after removal of CIDR devices (treatment D; n = 4 + 4). The hinds were run with crayon-harnessed stags from insertion of CIDR devices (12 March or 9 April) and blood samples were taken every second day to determine plasma progesterone. Further blood samples were collected for determination of plasma LH and progesterone via indwelling jugular cannulae every 2 h for 72 h from removal of CIDR devices. Hinds were allocated randomly to an initial ovarian examination by laparoscopy at either 16 or 20 h (A and B), or 12 or 16 h (C and D) after the onset of oestrus, with laparoscopy repeated at intervals of 8 h until either ovulation was recorded (A and B), or for four successive occasions (C and D). All hinds received cloprostenol injections 15 days after device removal. A total of 28 hinds (78%) exhibited oestrus and a preovulatory LH surge, with mean (+/- SEM) times to onset of oestrus of 44.6 +/- 1.0 h (A; n = 7), 37.4 +/- 2.0 h (B; n = 7), 16.3 +/- 1.7 h (C; n = 6) or 14.0 +/- 1.7 h (D; n = 8). Failure to exhibit oestrus or LH surge was most prevalent among hinds in treatment A early in the rut.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1990

Double blind comparative study of omeprazole and ranitidine in patients with duodenal or gastric ulcer: a multicentre trial. Cooperative study group.

We studied omeprazole and ranitidine in promoting duodenal ulcer healing in a multicentre trial by comparing the proportion of healed ulcers after two, four, and eight weeks of treatment. Altogether, 194 patients (143 men) were randomly allocated according to a prearranged treatment schedule to either drug and were treated double blind. Each received 40 mg omeprazole in the morning and a ranitidine placebo morning and evening or 150 mg ranitidine morning and evening with an omeprazole placebo in the morning. A total of 188 patients (94 taking omeprazole, 94 taking ranitidine) completed the trial. Sixty four (68%) omeprazole treated and 45 (48%) ranitidine treated patients had healed ulcers at two weeks, 91 (99%) omeprazole treated and 79 (88%) ranitidine treated had healed ulcers by four weeks, and 91 (100%) omeprazole treated and 86 (97%) ranitidine treated patients had healed ulcers by eight weeks. The overall difference in healing rates was significant (p = 0.0008, Mantel-Haenszel test). The differences were significant also at two weeks (20%, 95% confidence interval 5.6 to 34.4, p less than 0.01) and at four weeks (11%, 95% CI 3.7 to 17.3, p less than 0.01), but not at eight weeks (3%, 95% CI -0.5 to + 7.3, p = 0.25), using the chi 2 statistic, the study having a power to detect a 20% difference on 90% of occasions. After two weeks of treatment complete symptom relief was observed in 70 (74%) patients receiving omeprazole and in 58 (62%) receiving ranitidine. Diary cards showed a significantly lower percentage of days with pain in the omeprazole treated group (7.4% v 21.4%, p < 0.02) when assessed over either the first two weeks or over weeks three and four treatment. A total of 144 patients with healed duodenal ulcer were followed up, with no treatment, for six months. At the end of this period 19 (26%) of 74 patients healed with omeprazole and 17 (24%) of 70 patients healed with ranitidine were still in remission. A similar protocol was used for 46 patients (25 men) with gastric ulcer who were randomly allocated to treatment with omeprazole or ranitidine as described above. Forty patients (16 omeprazole, 24 ranitidine) completed trial. Thirteen (81%) omeprazole treated and 14 (58%) ranitidine treated patients had healed ulcers at four weeks; at eight weeks 14 (93%) omeprazole treated and 20 (87%) ranitidine treated patients had healed ulcers. These differences were not significant at four weeks (p = 0.25) or eight weeks (p = 0.96). Twenty seven gastric ulcer patients were followed up for six months and seven (58%) of the 12 omeprazole healed and five (33%) of the 15 ranitidine healed patients were in remission at six months. Unwanted adverse events were trivial except for one fatality in a 67 year old women, who died from bronchopneumonia and myocardial ischaemia while receiving treatment with omeprazole, which was judged to be unrelated to her death.

Aged↗

PubMed1991

Practice randomization and clinical research. The Indiana experience.

Thoughtful preparation of a research laboratory is an early step in designing a program for scientific investigation. The Division of General Internal Medicine at Indiana University has maintained a "laboratory" for outpatient clinical investigation for more than 15 years. In this report, we describe the structure and function of the General Medicine Practice in the Regenstrief Health Center on the campus of the Indiana University School of Medicine in Indianapolis. Specifically, we discuss the ongoing random allocation of subjects, the local resources for data management and tracking of patients' use of clinical services, and how combining this information system into a randomized primary care system has fostered successful ventures in clinical investigation.

Health Services Research↗

PubMed1992

Efficacy of milbemycin oxime against experimentally induced Ancylostoma caninum and Uncinaria stenocephala infections in dogs.

Twenty-eight helminth-naive Beagles, 16 to 26 weeks old, were inoculated with 200 third-stage larvae each of Ancylostoma caninum and Uncinaria stenocephala 5 times at weekly intervals. Dogs were randomly allocated to 4 groups of 7 on the basis of fecal egg counts, and treatments were randomly assigned. Groups 1 and 3 were given milbemycin oxime at a dosage of 500 micrograms/kg of body weight, PO, on day 0 and on days 0 and 30, respectively; groups 2 and 4 were nontreated controls. Fecal egg counts were evaluated before and after treatments. Feces were collected daily for 7 days after the final treatment for recovery of worms passed, and all dogs were euthanatized 7 days after the final treatment for recovery of worms retained. A 65.7% reduction from the pretreatment value for geometric mean hookworm egg count was found 7 days after the first treatment, and a 97.1% reduction 7 days after the second treatment. Although milbemycin oxime had 96.5% and 99.5% controlled efficacy against A caninum after 1 or 2 treatments, respectively, it lacked efficacy against U stenocephala. The geometric mean number of U stenocephala and the total number of hookworms retained after 1 or 2 treatments were not significantly different from the numbers retained by the corresponding control groups.

Ancylostoma↗

PubMed1978

[Therapeutic progress. Critical analysis of controled and non-controled clinical studies].

Methods used in the evaluation of therapeutic results in clinical oncology are criticized on the basis of recent examples of studies including the most-used antitumor agents. The need for random allocation of patients in comparative studies is underlined and the practical, statistical, and ethical limitations on randomization procedures are reviewed.

Ethics, Medical↗

PubMed1977

Hypertension during pregnancy, with and without specific hypotensive treatment. I. Perinatal factors and neonatal morbidity.

In a prospective study, women who were hypertensive before the 28th wk of gestation were randomly allocated into two groups: those who received specific hypotensive therapy (Ht) and those who did not (Hu). The outcome was compared with a random sample of the hospital population (S) ascertained after delivery. In both hypertensive groups there was a higher incidence of clinical signs of possible fetal distress and instrumental delivery. Although there was no difference between the groups in the distribution of birthweight above and below the mean for gestational age, the treated hypertensive group had an excess of infants with relatively smaller head circumferences for their gestational age compared with both the untreated hypertensive group and the hospital sample. Tube-feeding was also more frequent in the treated hypertensive group. In the untreated hypertensive group there were more infants whose neurological status was categorized as questionable or abnormal in the neonatal period, compared with the sample. The different problems encountered by infants in the two hypertensive groups emphasized the need for further study of these babies. Their development during the first year of life will be examined in a subsequent paper.

Female↗

PubMed1990

Ciamexone in endocrine orbitopathy. A randomized double-blind, placebo-controlled study.

The influence of ciamexone on the activity and course of endocrine orbitopathy was investigated. Fifty-one patients with active orbitopathy classes II-VI were allocated randomly to two groups: over a period of six months, 26 patients received 300 mg/day ciamexone and 25 patients received placebo tablets. In both groups, prednisolone was administered in addition in the first four weeks. Ophthalmological investigations and clinical tests as well as orbit sonography were carried out before as well as one, three and six months after the beginning of therapy. Before and after treatment, computer tomography of the orbit was performed. Symptoms and signs did not show any significant improvement one and six months after therapy. No differences between the two therapy groups were observed. Detailed examination did not reveal any preferential action of the product on individual parameters. Sonography and computer tomography showed no significant alterations of the thickness of the oculomotor muscles. Thus administration of 300 mg ciamexone once a day as compared with placebo did not show any effect on the course and activity of endocrine orbitopathy.

Adjuvants, Immunologic↗

PubMed1989

Dose-finding study for praziquantel therapy of Schistosoma haematobium in Coast Province, Kenya.

To assess the efficacy of low dose praziquantel regimens in comparison with standard 40 mg/kg dosing in the treatment of urinary schistosomiasis, a random allocation dose-finding trial was performed in children and adults from a Schistosoma haematobium endemic region in Coast Province, Kenya. Following an initial screening, 280 individuals with greater than or equal to 50 eggs/10 ml urine were randomly assigned to receive either 10, 20, 30, or 40 mg/kg of the drug in a single oral dose. Two to three months later, cure rates of 26%, 68%, 78%, and 84% were found for the 10, 20, 30, and 40 mg/kg doses, respectively. The results of 10 mg/kg oral dosing were significantly worse than for all other doses in terms of cure rate and of post-treatment prevalence of morbidity. The 40 mg/kg dosing resulted in a significantly higher cure rate than the 20 mg/kg doses; nevertheless, there was no significant difference between 20 mg/kg and 40 mg/kg doses in terms of mean post-treatment intensity of infection or post-treatment prevalence of hematuria or proteinuria. For large-scale control programs, oral 20 mg/kg praziquantel therapy for urinary schistosomiasis may prove as effective as the standard oral 40 mg/kg dosing for control of infection-associated morbidity and reduction of parasite transmission.

Adolescent↗

PubMed1989

A prospective randomized comparison of fine needle aspiration biopsy and fibreoptic bronchoscopy in the investigation of peripheral pulmonary opacities.

Twenty-nine patients, aged 66(+/- 7) years with a peripheral pulmonary opacity (mean diameter 3.6 +/- 1.8 cm) believed to be a tumor, were randomly allocated to initial investigation by either fibreoptic bronchoscopy or percutaneous fine needle aspiration biopsy, the latter performed under fluoroscopic control. The patients proceeded to the alternative investigation in the event of the first failing to achieve a diagnosis. Malignancy was confirmed by the initial procedure in 14/15 patients randomized to fine needle aspiration biopsy but only in 1/14 patients randomized to fibreoptic bronchoscopy (P less than 0.01). Overall, these figures were 25/28 fine needle aspiration biopsy and 2/15 fibreoptic bronchoscopy (P less than 0.01). These results confirm the clinical suspicion that fine needle aspiration biopsy is far more likely than fibreoptic bronchoscopy to establish the presence of malignancy in peripheral pulmonary opacities.

Aged↗

PubMed1990

The capitation study. 1. Does capitation encourage "supervised neglect'?

Four matched pairs of geographically and socially contrasting areas of Britain were randomly allocated within pairs to either a capitation or fee-for-service payment system for the dental care of children in a 3-year clinical trial. Measurements were made on the dental health of randomly selected 5-6 and 14-15-year-old patients and the views of their parents elicited. Patterns of treatment were also gained from the clinical records of randomly selected patients. In addition, the views of the dentists taking part, of the profession's representatives, and of the administrators of the systems were obtained. No evidence of systematic neglect could be found among the children treated under capitation, but they had fewer fillings, more untreated diseased teeth and similar disease levels to their counterparts treated under fee-for-service. Dentists in capitation carried out fewer fillings, fewer extractions, took fewer radiographs and saw their patients less frequently than their fee-for-service colleagues.

Adolescent↗

PubMed1990

Serotonin antagonism reduces the adverse symptoms of beta blockade.

Beta-adrenoceptor antagonists (beta blockers) are a well-established first-line treatment for hypertension, but they have been associated with unwanted symptoms including cold extremities, lethargy, and nightmares. Ketanserin is a serotonin S2-receptor antagonist that has previously been shown to reduce blood pressure in hypertensive patients by reducing systemic vascular resistance. Hypertensive patients whose sitting diastolic blood pressure was greater than or equal to 95 mmHg, despite at least 4 weeks therapy with an optimal dose of beta blocker, were selected for the study. The beta-blocker dose remained constant throughout the study, but patients were randomly allocated to receive ketanserin 20 mg twice daily, ketanserin 40 mg twice daily, or bendrofluazide 5 mg each morning plus placebo at night in addition to the beta-blocker therapy. One hundred and forty two patients completed the symptom questionnaire at randomization and after 12 weeks treatment. The treatment groups were well matched for age, sex, weight, and blood pressure. Blood pressure was reduced significantly by all treatments, and there were no between-group differences. Bendrofluazide adversely affected alertness (p less than 0.05) and concentration (p less than 0.01) whereas ketanserin had no significant effect and the ketanserin 20 mg twice daily group had better concentration than the bendrofluazide group (p less than 0.05). Ketanserin treatment reduced the incidence of nightmares (p less than 0.05 for 20 mg twice daily and 40 mg twice daily) and was an improvement over bendrofluazide treatment in this respect (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Antagonists↗

PubMed1979

Randomized clinical trials in the evaluation of surgical innovation.

Randomized clinical trials are widely accepted as the standard for evaluation of therapeutic innovation in many fields of medicine. The three basic components of such trials (concurrent comparison, random allocation, and objective observation) are designed to control four forms of bias (chronology bias, susceptibility bias, compliance bias, and observation bias) that may interfere with the interpretation of the results of a study. Only 2% of the articles evaluating therapeutic maneuvers published in the Journal of Neurosurgery have attempted to use concurrent controls. Only one of 863 such articles met the criteria for a randomized clinical trial. Reasons for underutilization of such trials in neurosurgery are discussed and suggestions for their wider use are offered.

Clinical Trials as Topic↗

PubMed1990

Phenytoin sodium and magnesium sulphate in the management of eclampsia.

Twenty-two patients with eclampsia were randomly allocated to receive either intravenous phenytoin sodium or intravenous magnesium sulphate. The groups were comparable. No side-effects occurred and therapeutic levels were obtained in both groups. While none of the 11 patients managed with magnesium sulphate had further convulsions, four of the 11 treated with phenytoin sodium did and were subsequently effectively treated with magnesium sulphate. These results suggest that phenytoin sodium is not as effective an anticonvulsant in eclampsia as is magnesium sulphate.

Adolescent↗

PubMed1979

Anticoagulants in the treatment of small cell carcinoma of the bronchus.

The object of this study was to see if the addition of anticoagulants to a regimen of cytotoxic drugs would improve the prognosis in patients with small cell carcinoma of the bronchus. Twenty-four patients were randomly allocated to receive chemotherapy or chemotherapy plus anticoagulants. The median survival in the group receiving the anticoagulants was not improved.

Antineoplastic Agents↗

PubMed1992

High frequency jet ventilation: use of the Bain system for entrainment.

The use of a Bain system to convey anaesthetic gases for entrainment during high frequency jet ventilation (HFJV) was evaluated by examining the effect of varying the fresh gas flow (Vf) on the end-tidal carbon dioxide (PECO2) in 46 ASA physical status I and II patients undergoing extracorporeal shock-wave lithotripsy (ESWL). Anaesthesia was induced with methohexitone (1-2 mg.kg-1), fentanyl (1-1.5 micrograms.kg-1) and vecuronium (0.1 mg.kg-1). After endotracheal intubation with a Mallinckrodt Hi-Lo Jet cuffed endotracheal tube, the patient was immersed in a water bath and HFJV at 150 breaths per minute was instituted with an Acutronic AMS 1000 jet ventilator attached to the side channel of the Hi-Lo tube. A Bain system was attached to the proximal end of the endotracheal tube to provide gases for entrainment. Anaesthesia was maintained with an intravenous infusion of methohexitone (5 mg.kg-1.h-1) and 50% nitrous oxide in oxygen for both the jetted and entrained gases. PECO2 was determined at 5-min intervals by a single-breath technique using a calibrated Engstrom Eliza capnograph. Thirty patients were randomly allocated to receive Vf's of 50 (Group 1), 75 (Group 2) and 100 (Group 3) ml.kg-1.min-1, respectively. A further eight patients (Group 4) received a Vf of 100 ml.kg-1.min-1 for 15 min, 75 ml.kg-1.min-1 for the next 15 min and 50 ml.kg-1.min-1 thereafter. In a further group of eight patients (Group 5), Vf was initially 25 ml.kg-1.min-1 for 10 min and was then switched off for the remainder of the procedure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗