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PubMed1986

Preoperative cervical dilatation: a trial of laminaria tents and prostaglandin F2 alpha gel.

Surgical damage to the cervix in patients undergoing termination of pregnancy may be responsible for serious complications in subsequent pregnancies. Sixty nulliparous women undergoing first trimester termination of pregnancy were randomly allocated to 3 treatment groups, one using laminaria tents preoperatively, one using intracervical PGF2 alpha gel preoperatively and one using no pretreatment. Results showed clear benefits in the laminaria group, in terms of achieving preoperative cervical dilatation and ease of further operative dilatation. Laminaria tents were superior to PGF2 alpha gel which was, in turn, superior to no pretreatment. There were no differences in blood loss or postoperative complications among the 3 groups. Laminaria tents provide a cheap, effective and safe method of reducing the risk of cervical damage in women undergoing surgical termination of pregnancy.

Abortion, Induced↗

PubMed1993

Modelling the spread of HIV among intravenous drug users.

This paper considers a random allocation model for the transmission of HIV by needle sharing among a group of intravenous drug users who are friends or relatives (buddy-users). A Markov chain approach is used to track the increase in infectives in a stable group of such IVDUs, some of whom are HIV positive. The model is modified to allow for the replacement of infectives in the group, with the group size remaining constant. Further problems are suggested.

HIV Infections↗

PubMed2002

The effects of different environmental education programs on the environmental behavior of seventh-grade students and related factors.

This study used random allocation to separate out groups of students from four Taipei junior high schools, each of which underwent a different environmental-education program, in order to examine the effects of such programs on students' environmental behavior and related factors. Results indicate that Taiwanese junior high schools should coordinate the teaching of environmental programs with other school activities to obtain the most ideal results.

Adolescent↗

PubMed1987

Early pregnancy termination with antiprogestins: a comparative clinical study of RU 486 given in two dose regimens and Epostane.

Mifepristone, (RU 486, Roussel Uclaf, Romainville, France), a progesterone (P) receptor blocking agent, and Epostane, (WIN 32,729, Sterling-Winthrop, Guildford, United Kingdom), a P synthesis inhibitor, were compared for their ability to terminate early human pregnancy. Seventy-eight healthy women, with a gestational length of less than 49 days from the last menstrual period and who requested termination of pregnancy, were recruited to the study. The patients were randomly allocated to three treatment regimens: (1) Mifepristone 25 mg bid for 7 days; (2) Mifepristone 50 mg bid for 7 days; and (3) Epostane 200 mg qid for 7 days. The results of the study confirmed that both compounds are potent abortifacients in early human pregnancy. No difference in efficacy was seen between the two dose regimens of Mifepristone, which both resulted in 61% complete abortions. Seventy-three percent aborted completely in the Epostane group. Subjective side effects, especially nausea, were more common in the women treated with Epostane, but no serious side effects were seen.

Abortion, Induced↗

PubMed1984

Frozen shoulder: prospective clinical study with an evaluation of three treatment regimens.

Forty-two patients with frozen shoulder were followed up closely for eight months. They were all taught pendular exercises and randomly allocated to one of four treatment groups: (a) intraarticular steroids, (b) mobilisations , (c) ice therapy, (d) no treatment. This study has shown that there is little long-term advantage in any of the treatment regimens but that steroid injections may benefit pain and range of movement in the early stages of the condition.

Adult↗

PubMed1987

A comparative study of Norinyl 1/35 versus Norinyl 1/50 in Belgrade, Yugoslavia.

A comparative study of Norinyl 1/35 and Norinyl 1/50 was conducted at the Dom Zdravlja Stari Grad in Belgrade, Yugoslavia. The study sought to evaluate the differences in continuation rates as well as the frequency of selected side effects which might contribute to method discontinuation. The trial included 299 women who were randomly allocated to one of the two oral contraceptives. In the Norinyl 1/35 group, significantly more women (p less than .05) reported a complaint of vaginal discharge as well as an increase in the occurrence of vaginal discharge compared to the Norinyl 1/50 group. There was no significant difference in continuation rates or for particular discontinuation reasons for the Norinyl 1/35 and Norinyl 1/50 groups. No accidental pregnancies were reported during this study. Both oral contraceptives appear to be safe and effective; there appears to be no difference in the acceptability of one oral contraceptive over the other among this group of Yugoslavian women.

Adult↗

PubMed1986

Determining optimal therapy--randomized trials in individual patients.

Although the treatment of an individual patient in routine clinical practice has been likened to an experiment, the method is so susceptible to bias that we have come to demand multi-patient, double-blind, randomized controlled trials on matters of efficacy. Unfortunately, such trials have not or cannot be carried out for many clinical disorders; even when they have been executed their results may be difficult to extrapolate to individual patients. To resolve this problem, we have begun to use double-blind randomized trials in which a single patient undergoes a series of pairs of treatments, consisting of one active and one placebo or alternative treatment per pair, with the order determined by random allocation. Appropriate treatment targets (signs, symptoms, or laboratory tests) are used as the measure of efficacy, and the trial is continued until efficacy is established or disproved. We describe such a trial, which resulted in a dramatically beneficial modification of treatment in a patient with partially reversible airflow limitation. We have established a clinical service that facilitates the widespread use of the method in our community.

Aged↗

PubMed1982

Randomized comparative study of culdoscopy and minilaparotomy for surgical contraception in women.

Informed, healthy, volunteering women seeking interval sterilization were randomly allocated either to culdoscopy or to minilaparotomy. Data concerning the operation and follow-up to six weeks post-operation were analyzed for 199 women in the culdoscopy group and 196 in the minilaparotomy group. Major complications, both at operation and subsequently, occurred only in the vaginal procedure group (3%). Minor complications occurred in 3.6% of women in the minilaparotomy group, the majority of these involving the abdominal wound. In the women operated vaginally, minor complications occurred in 1.5%. Failure to perform the intended procedure on the fallopian tubes occurred in 10.6% of culdoscopy cases and 0.5% of minilaparotomy cases. It is concluded that the vaginal approach cannot be recommended except for surgeons experienced in vaginal surgery.

Adult↗

PubMed2001

Knowing me, knowing you: reciprocal self-disclosure in Internet-based surveys.

Candid self-disclosure is desirable for many behavioral science studies. Although there is ample evidence that self-disclosure is increased when people communicate or participate in research over the Internet, few studies have looked at ways of increasing this effect. In the present pilot study, participants were randomly allocated to either a condition in which they received self-disclosing information about the experimenter (and then moved on to the study) or were directed straight to the study. Participants completed six open response questions on the Internet. Participants who received the experimenter disclosure divulged a significantly higher quantity of information about themselves, but their answers were not scored as significantly more revealing or intimate than those participants who did not receive the experimenter disclosure. Implications for conducting research over the Internet are discussed.

Adult↗

PubMed1985

Retrospective information from questionnaires. II. Intrarater reliability and comparison of questionnaire types.

Medical and dietary consumption histories obtained at two times from cases or controls and their next-of-kin as part of a study of colon cancer in the five Pennsylvania counties of the Philadelphia metropolitan area were compared. The case population was confined to whites aged 45-69 years who had resided in the region for at least two years prior to diagnosis and were diagnosed with colon cancer after July 1, 1976. Controls were selected using an area probability sampling scheme and were frequency-matched to the case group. Questionnaires for randomly selected subsamples of cases and controls were administered by interviewers; questionnaires for next-of-kin were randomly allocated to be self- or interviewer-administered. Agreement when respondents received the interviewer-administered questionnaire at both interviews was greater than when the self-administered questionnaire was used. Medical variables exhibited high agreement, the percentage agreement exceeded 80 for over 80% of the comparisons, the kappa statistic exceeded 0.6 for half of the comparisons. Diet histories were more variable (average agreement ranging from 56% to 67% and average kappa values from 0.16 to 0.40 for the different comparisons).

Beverages↗

PubMed1991

Comparative bioavailability of orally and vaginally administered progesterone.

OBJECTIVE: To study the pharmacokinetics of progesterone (P) in healthy premenopausal female volunteers to compare the bioavailability of orally or vaginally administered hormone. DESIGN: Subjects were randomly allocated to receive either oral P or a vaginal pessary then crossed over to the alternate preparation 1 month later. SETTING: The study was conducted in outpatient setting. SUBJECTS: All subjects were healthy, normal female volunteers who underwent a physical and gynecological examination before the study. None were using oral contraceptives. Ten subjects (mean age 32.6 +/- 7.3 years) entered the study and all completed it. INTERVENTIONS: Progesterone was administered as 200 mg of micronized hormone or as a pessary containing 400 mg. MAIN OUTCOME MEASURE: Plasma levels of P were measured by radioimmunoassay to test the apriori hypothesis of similar bioavailability. RESULTS: Peak plasma P concentrations attained within 4 hours after oral administration ranged from 8.5 to 70.6 ng/mL, whereas after vaginal administration the peak levels were attained within 8 hours and ranged from 4.4 to 181.1 ng/mL. Considerable interindividual variation was noted. Area under the plasma concentration-time curve for the two formulations was not significantly different (F = 1.09; P greater than 0.1; ANOVA). CONCLUSIONS: The two formulations had similar bioavailability.

Administration, Oral↗

PubMed1986

A possible mechanism of action of danazol and an ethinylestradiol/norgestrel combination used as postcoital contraceptive agents.

Twenty-seven women requesting postcoital contraception were randomly allocated to take an ethinylestradiol/dl-norgestrel combination or danazol. Urine specimens were assayed for luteinising hormone (LH) and pregnanediol-3-glucuronide (P3G) levels from the day of the postcoital treatment to the next period. In addition, the urine samples of these recruits and 12 additional women were assayed for the Beta-subunit of human chorionic gonadotropin (B-hCG). A consistent pattern of alteration in urinary steroids was lacking, indicating a heterogeneous effect on ovarian function. There was no evidence of early pregnancy in successfully treated cases. We suggest that the main mechanism of action of these drugs is at the endometrial level.

Chorionic Gonadotropin↗

PubMed1984

Chronobiological approach to the treatment of essential hypertension: preliminary data.

The effect on bioperiodic parameters of hypertension elicited by the beta-blocking agent mepindolol, administered as a single dose of 10 mg at 8 a.m. vs 10 mg at 8 p.m., was evaluated in this study. Circadian blood pressure monitoring was performed in age-matched patients with essential hypertension after a two-week wash-out period with placebo and four weeks treatment. Patients were randomly allocated to one of the two treatment groups. Standard blood chemistry and electrocardiogram were performed at the beginning and end of the treatment period. Statistical analysis of blood pressure circadian rhythm characteristics (mesor, amplitude, acrophase) showed a significant decrease of mesor of systolic and diastolic blood pressure in both groups. Values of the mesor were not significantly different between the two groups. Interestingly, changes of acrophase and amplitude induced by the drug were different in regard to the time mepindolol was administered. Side effects were generally mild.

Adult↗

PubMed2006

The effect of pre-calving environment on the development of digital dermatitis in first lactation heifers.

Digital dermatitis is commonly reported to be most severe in first lactation heifers. It has been suggested that this initial infection is followed by the development of a limited immunity to the organisms which cause digital dermatitis. If this is the case then exposure to digital dermatitis prior to calving should reduce its severity after calving. A study was undertaken to examine whether such exposure significantly affected the development of digital dermatitis post-partum. Twelve weeks prior to calving, 60 Holstein heifers were blocked on the basis of their antibody titre to Borrelia burgdorferi and randomly allocated to one of three pre-calving environments: clean straw, used straw or cubicles. There was no significant effect of pre-calving environment on the development of digital dermatitis after calving indicating that "exposure" pre-calving did not reduce the development of digital dermatitis after calving. The most important factors determining the development of digital dermatitis after calving were presence of absence of visible lesions of digital dermatitis at Week-12 and at calving.

Animals↗

PubMed1995

Effect of nickel-titanium engine-driven instrument rotational speed on root canal morphology.

Thirty-six mesial canals in 18 extracted human mandibular molars were randomly allocated to three experimental groups. Specimens were prepared and evaluated using a modified Bramante technique. Teeth were sectioned at the midroot and apical regions. Canals were prepared with the Lightspeed instruments rotating at 750, 1300, or 2000 rpm. Digitized uninstrumented and instrumented canal images were compared via subtraction software. There was no significant difference (p <0.05) among the three experimental groups in the amount of dentin removed, canal transportation, or the ability of the instrument to remain centered in the canal.

Alloys↗

PubMed1985

A comparison of prostaglandin E2 pessaries and laminaria tents for ripening the cervix before termination of pregnancy.

Forty primigravid women aged 15-45 years were randomly allocated to receive either an intravaginal pessary of 3 mg prostaglandin E2 (PGE2) or an intracervical 5-mm laminaria tent (LT) 12-16 h before termination of pregnancy at 6-14 weeks gestation. The degree of dilatation of the cervix at operation and its resistance to further dilatation during the procedure were assessed by a 'blind' operator. Laminaria tents were more effective in achieving dilatation and softening of the cervix than were PGE2 pessaries and in 40% of women no further dilatation was necessary. There were no associated side-effects or complications. A cervical tear occurred in two of 20 patients treated with PGE2 pessaries and all 20 required further dilatation of the cervix. Laminaria tents provide a simple, safe, acceptable and effective means of 'ripening' the cervix prior to termination of early pregnancy.

Abortion, Therapeutic↗

PubMed2005

Pseudo cluster randomization: a treatment allocation method to minimize contamination and selection bias.

In some clinical trials, treatment allocation on a patient level is not feasible, and whole groups or clusters of patients are allocated to the same treatment. If, for example, a clinical trial is investigating the efficacy of various patient coaching methods and randomization is done on a patient level, then patients who are receiving different methods may come into contact with each other and influence each other. This would create contamination of the treatment effects. Such bias might be prevented by randomization on the coaches level. The patients of a coach constitute a cluster and all the subjects in that cluster receive the same treatment. Disadvantages of this approach may be reduced statistical efficiency and recruitment bias, as the treatment that a subject will receive is known in advance. Pseudo cluster randomization avoids this, because in pseudo cluster randomization, not everybody in a certain cluster receives the same treatment, just the majority. There are two groups of clusters: in one group the majority of subjects receive treatment A, while a limited number receive treatment B. In the other group of clusters the proportions are reversed. The statistical properties of this method are described. When contamination is present, the method appears to be more efficient than randomization on a patient level or on a cluster level.

Bias↗

PubMed1991

An investigation of the role of diet and burn injury on wound healing.

Forty-four rats underwent standard laparotomies and were randomly allocated to four groups according to injury (control or burned) and diet (maintenance or protein depleted). Wound healing was assessed tensiometrically on the 14th postoperative day. The energy intakes of the four groups were comparable. Both injury by burning and protein depletion caused significant weight loss. The peak force applied to the laparotomy wounds was unaltered by burning, but protein depletion caused a significant reduction in wound strength. It is concluded that any impairment in wound healing in burned patients is more likely to result from inadequate feeding rather than the injury itself or any resultant weight loss.

Animals↗